installed the 450R carb and WOW.....!!!

[QuadJunkies]

what A nice enhancement..... :D The throddle responsose is gonna be VERY impressive!! :blah: Im not sure what all the hype was about having to make modifications, but we were still able to keep the choke AND the Hot start can be nicely tucked away:)
I was a little on the fat side with my old Carb,Im now lean, ditched the Air box, I think I may have to change my gearing in fears I may wheelie over :o :p It sounds soooooo much betterthan my stock Carb, I now know that my stocker was trashed for some time now after hearing how this sounds... I cant wait to try it at the track!!!:macho Anyone that can get there hands on one............. DO IT!! ;)

[Rico]

How was fit and finish?? What did you have to do to get it to work.

Did I read it correctly that you DITCHED the airbox?? Meaning the filter is bolted directly to the carb??


Some say the 450R shocks are a must to put on a 400ex, even though the stroke is wrong, grinding has to be done, etc, etc.

[Dave400ex]

Yes let us know about this. I am with Rico, I would be running the airbox for sure, so how did that mount up?

[khen]

That's good news QuadJunkies!!! I just got mine in yesterday, but I'm still waiting for the 450R cable from servicehonda. I have a few questions:

1- What pilot/main jets did you use in the 450R carb and what did you have on your old one(for reference).

2- Did you use the 400EX fuel hose, or did you use the 450R's?

3- Did you have to modify the choke so it would clear the fuel petcock?

[yfz450admirer]

I used the stock pilot jet and a 185 main jet, 4th notch on the needle, air/fuel screw 3 1/2 turns out. On the stock carb I ran the same set-up except for less turns on the air/fuel screw.
I used the fuel hose from the 450R.
The yellow plastic choke handle will not clear the petcock. My quad starts easily by just pumping the throttle 2 times before pushing the starter.
The hot start is not really needed, although I use it at times.

The carb works great on my track.

[QuadJunkies]

would you like some pics and Ill sit down with Troy and give more details tonight on it if you like ? :)

Yes, I thought Troy said he had to ditch the airbox, but Ill dbl. check on that;)
Fit and finish was VERY simple,its on good and tight,I still have the choke evenand the hot start is going to just be ziptied out of site.... now its all about just getting the jetting and pilot dialed in.... :ermm:

[QuadJunkies]

Originally posted by yfz450admirer
I used the stock pilot jet and a 185 main jet, 4th notch on the needle, air/fuel screw 3 1/2 turns out. On the stock carb I ran the same set-up except for less turns on the air/fuel screw.
I used the fuel hose from the 450R.
The yellow plastic choke handle will not clear the petcock. My quad starts easily by just pumping the throttle 2 times before pushing the starter.
The hot start is not really needed, although I use it at times.

The carb works great on my track. did you completley remove your choke or just cut the tab dowbn a bit?? Thts what he done to mine :) Als, what Elev. and temps are you at right now??? Im at 2800 and its Averaging this wk in the 40's, we race in the 20's

[hondarider2006]

I want to see some pictures. Sounds like a good mod that I might have to look into....:)

[QuadJunkies]

Originally posted by khen
That's good news QuadJunkies!!! I just got mine in yesterday, but I'm still waiting for the 450R cable from servicehonda. I have a few questions:

1- What pilot/main jets did you use in the 450R carb and what did you have on your old one(for reference).

2- Did you use the 400EX fuel hose, or did you use the 450R's?

3- Did you have to modify the choke so it would clear the fuel petcock? Ill get more info tonight ;)

[khen]

Thanks QuadJunkies and yfz450admirer! I'm looking forward to trying this out, hopefully the cable comes in today.. I didn't think to order a 450R fuel hose though :ermm: Hopefully I can make do without.

[Rico]

I forgot to ask you Tina... Why you didn't put this in our own 400ex forum........:devil: YOu have the power woman..:macho

also for me, check the clearance from the top of the carb to the gas tank. I run a clarke oversized tank and I don't think the carb is going to work with the MUCH larger tank....:ermm:

[QuadJunkies]

Originally posted by Rico
I forgot to ask you Tina... Why you didn't put this in our own 400ex forum........:devil: YOu have the power woman..:macho

also for me, check the clearance from the top of the carb to the gas tank. I run a clarke oversized tank and I don't think the carb is going to work with the MUCH larger tank....:ermm: I guess I could ...... :D Make Ill copy the info over there ;)

[QuadJunkies]

Here are some pics I took...
We need to attach a hose clamp to keep fuel from leaking, re are rejetting tonight so I can ride it tomorrow at the track that has the Payette Round for WORCS...Maybe Ill get some video of it...:D

[QuadJunkies]

there will be a hose clamp where that wire is .Troy said an Airbox will work, Il get more info in a few minutes on that :)

[QuadJunkies]

Im done with riding in mud(if I can help it that is lol) I dont run threw creeks ect so no air box will be fine for my application for now, in the future I may invest in an afteramarket box.

[QuadJunkies]

Choke is stil attached just cut back some....Im sure overtime we will make things look a little nicer on the set up as well...

[QuadJunkies]

Rico~~ heres the clearance question you needed.....sorry for the blur.. let me know if its too hard to see and Ill try and get a better one ;)

[44oEX]

see and you didn't believe me :D

[QuadJunkies]

well, so much for testing out my carb tomorrow.. I blew a head gasket while jetting.....It hasnt ran good during a race and had a weird noise, now we know what the other noise was..... :rolleyes: :mad: Im not sure if its due to a bad jug or the Gasket ect.... We may go back and just put my 426 back on...:( I was REALLY looking forward to trying the 440 too...:ermm:

[QuadJunkies]

Originally posted by Rico
How was fit and finish?? What did you have to do to get it to work.

Did I read it correctly that you DITCHED the airbox?? Meaning the filter is bolted directly to the carb??


Some say the 450R shocks are a must to put on a 400ex, even though the stroke is wrong, grinding has to be done, etc, etc. You could prol. come up with something, the intake boot was a little short and the air box on ours was pretty much already destroyed so no big loss on my end. You have to replace the fuel line and you have to hog out the intake boot. Thats about it ...!!

[ZSK]

Get the headstuds;)

[QuadJunkies]

Originally posted by ZSK
Get the headstuds;) thats what I hear.... ;) Head bolts and a flex Gasket or something like that....:confused: Im not sure what kind of gaskets this kit cam with for certain but we will get Er figured out and if not then Ill just slap my 426 bakc in....Also, what about Vavle springs??? Im sure my 426 had some but not sure what they were

[ZSK]

Originally posted by QuadJunkies
Head bolts and a flex Gasket or something like that....:confused:

That's what it took to get mine figured out. It blew the flexsteel on after about 18 hours, put a cheap kit in and it blew in about 3. I installed the HD headstuds, and the flexsteel gaskets and didn't have a problem. Race the rest of the season on it and numerous trail rides.

[muddy400EX]

was the 450 carb easy to put on? did it require any mods? and does anybody know if it would do nething on a stock motor?

[QuadJunkies]

Originally posted by muddy400EX
was the 450 carb easy to put on? did it require any mods? and does anybody know if it would do nething on a stock motor? Did you read ANYTHING I posted and see ANY pof the pics??? :huh That should be ALOT of info that your asking about.... :o

[twisted threads]

Originally posted by QuadJunkies
Did you read ANYTHING I posted and see ANY pof the pics??? :huh That should be ALOT of info that your asking about.... :o

LMAO!!!!!

About the head gasket......... I would just get some studs and see how that works. I have only blew one head gasket since my 440 has been together and I run stock head studs.:cool:

[khen]

I got 450R carb installed today. It sounds really nice! The cable comes in tomorrow for it so hopefully I can go see what it does sometime this week. Here are few pictures of my installation.

I ended out pulling the vent tube off of the top, cutting it down and caping it and then drilling out the side vent instead like Laz suggested.. I found that otherwise my tank would be resting on it. I also did a makeshift choke and moved the airbox forward about an inch to make up for the shorter carb.

[khen]

The carb is in there as solid as the stock one.. I did have to ream out the boots quite a bit to make them fit correctly, especially the airbox boot. Here's a side view of my makeshift choke, I just have to push up on it at the bottom where the 'L' bend is.

[QuadJunkies]

NICE illustration!!! Thanks for posting some pics.!!.. mine were blurry.... :o :p

[khen]

Originally posted by QuadJunkies
NICE illustration!!! Thanks for posting some pics.!!.. mine were blurry.... :o :p Nah, your pictures look good.. I just never take pictures when I do my mods and people always PM me asking for pics. So I thought I'd be proactive this time. :)

I'm excited to hear another performance review of this carb. I was hoping to try mine out this week at the track, but mother nature suprised us with 4-5 inches of snow this morning.. :(

[EXDUNER127]

So the 450R carb just bolts right up to the 400ex, just like the 400ex carb did, without needing anything? Is the 42mm to big for a the 400ex with aftermarket cam and piston, and porting because the fcr only goes to a 41. So when i buy the 450r carb the only other thing i need is the gas line and throttle cable to make it work? How much did you guys get yours for?

[44oEX]

Originally posted by 44oEX

Some people just warm up the intake boot with warm ( boilling water ) and then jam the carb in there. it might work but that will pop out. So don't do it

The right way to do it is like yfz450admirer said ( i told him how )
take the intake boot off of the motor. then use a dremel or sand paper ( slower but cheaper then a dremel lol) or grinding rock on a drill or something, and make the hole in the boot a little bigger. don't go to big. On mine I still have to fight it a little to make it go in but it's just cause I got sick of sanding :D . ones you have the hole the size you what ( make sure it's round so it won't leak ) put the intake back on the motor then work on the boot that goes from the air box to the carb. That one is a little harder cause it's only a thin wall, so you don't want to take to much out. Take out a couple mm if you can force the carb i then you good.

One's that is done you basicly done. see it's not hard it just takes a little time to get it the right size. The only problem I got was that the stock choke lever ( 450R ) it will NOT clear the gas line ( use the 450 one just cut it a little sorter so it won't kink. and use a small clamp to hold it on the petcock) The choke thing is not that big of a deal. you don't need it for summer riding. I have to have one ( I made a costom one ) but it's only cause the winter wheater is around -10 to -20

You can use ( you have to ) the stock 450R gas cable with the EX's trottle.

Know for how it runs. well yes Rico if you give it gas when it's warming up it will stall. But that is kind of a good thing. you have to let the motor warm up before you ride anyway right.

But as you don't have to give it any gas anyway. unlike most quads I've seen, one's it starts it will run on it's own with no gas and it won't stall on it's own. ( if you jetting is any good ). Mine runs really smooth on idle. and it's a 500 stroker with a wild grind cam. so it sould be even better on a normal size motor ( 400-440)
and the idle is smooth from cold start up all the way up to the end of a couple hour run.

One's the jetting was good the trottle risponce is really good. I can give it full trottle when idling and it will rev up right away. as long as you pilot screw is set properly you won't have any problem. if it's not well then it will complain a little but I mean it's normal if the jetting is off.

speaking of jetting. I was having trouble with the stock carb on the 500. I could just not get it like I wanted. it was always complaining. well the 450 carb is easy to jet and even if you are not spot on with the main or needle it's no big deal. ( well it is but I mean it will still run good so check the plug. )

And as for falling of I didn't have any problem yet. and this is not a show quad it is riden hard. and no dunes it's a rough trail and pit ( jumps ) riding. just make sure the boot is not to tight. And put the clamp pretty tight. but I would not worry about the carb falling off.

I think I awnsered all the Q?'s if I misted any let me know.

oh and for jetting start of with a stock pilot jet and something around 170 for the 440. then work from there.

custom choke

http://www.imagestation.com/picture/sraid153/pcd6b18360272bc6298a177229d033903/f5919b89.jpg

side. you can see the sorter gas line and the clamp I used. And how tigh the choke is
http://www.imagestation.com/picture/sraid153/p72ee5b2348811cf076dd64a6737e4437/f5919b83.jpg

[44oEX]

there you go that sould answer all the Q?

[QuadJunkies]

Originally posted by 44oEX
there you go that could answer all the Q? WEll..................I think all this about covers it........!!! :eek2:

[Rico]

So your saying it just bolts up and your ready to ride...:confused:


:chinese: :scary: :devil:

[QuadJunkies]

Originally posted by Rico
So your saying it just bolts up and your ready to ride...:confused:


:chinese: :scary: :devil:

Well. I know mine is !!! :blah:
We got the Duncan racing kit installed tongiht, I have two more runs on it early in the morning before I go race it tomorrow night, we may some of the changes listed and WOW... I think Im gonna REALLY like this set up...:devil: Ill let you know how it runs tomrorow!:macho

[QuAdEr 317]

i did read all this but i still dont understand if you can stil use a airbox cuz in ur picture u have the boot directly to the filter n i would still need to use the airbox

[khen]

Originally posted by QuAdEr 317
i did read all this but i still dont understand if you can stil use a airbox cuz in ur picture u have the boot directly to the filter n i would still need to use the airbox You can use the airbox you just have to move it forward about 1". Here's a picture of how I mounted mine for now. I just put a big washer on the existing mount bolt to hold it down.

[QuadJunkies]

Well, I raced half the night on it(decided to run the Preedator the rest of the night,didnt like my tire set up) and its a great add on! The throddle response it sooo good.... :cool: When I raced inthe heat race it was sputtering and sounding as if I was hittin my Rev limiter but it just needed more fuel and that took care of that.. We still want to make some changes to make it all fit better but I have no complaints. GREAT upgrade to make!! :)

[khen]

Cool! that's good news QuadJunkies. :D Do you recall what jets you ended out with? and what needle position?

[QuadJunkies]

Originally posted by khen
Cool! that's good news QuadJunkies. :D Do you recall what jets you ended out with? and what needle position?

Ill find out tonight from Troy just to make sure ,but I know I had to jet down a little and I think same with the pilot and a full turn on the fuel . I needto take it out and runn it in 5th gear so I can get a full feel for it wide open :macho but I think were pretty darn close if not dead on ...:)

[QuadJunkies]

My jetting is a 180 main,it came stock with a 190
needle is set one position leaner than stock
pilot is a 45 Stock was a 38 :huh (weird)
Fuel screw -2 turns out


Isnt that weird, it wouldnt idle with a 38-40-or a 42, 45 starts up and runs like a champ.! Temps 35 degrees ran good 40-45 it runs fat.

[Hotdog]

i seen that service honda is only selling them for 165 bucks. that cheap.

[44oEX]

Originally posted by QuadJunkies
My jetting is a 180 main,it came stock with a 190
needle is set one position leaner than stock
pilot is a 45 Stock was a 38 :huh (weird)
Fuel screw -2 turns out


Isnt that weird, it wouldnt idle with a 38-40-or a 42, 45 starts up and runs like a champ.! Temps 35 degrees ran good 40-45 it runs fat.

a 450R comes stock with a 118 main and a 45 pilot:huh

[QuadJunkies]

Originally posted by 44oEX
a 450R comes stock with a 118 main and a 45 pilot:huh well, this Carb had a 190 in it when we got it from our freind ... Ill dlb. check on it I know his honda is pretty modified so ill dlb. check and make sure I had that correct... :o ;)

[44oEX]

well if it's modded a 190 makes sense but not stock

[QuadJunkies]

Originally posted by 44oEX
well if it's modded a 190 makes sense but not stock Well I asked him and he said nothing had been done to the Carb ..So now Im not sure why it had a 190 in it :huh . Thats why my hubby assumed a 190 was stock....:confused: lol

So now my question to you all is... Can this Carb being that much BIGGER HURT performance?? Maybe not so much on a Modified quad but what about ones that are just stock or piped?? Ive heard that sometimes when you go bigger Carb it can hinder your gains somewhere between top end to bottom......This mihgt be a good thing to post for those peeps considering one ...

[Metzroth]

Yeah I'm looking into it but all I will have is HMF full system K&N Air filter and open airbox lid. Will the 400ex jets work on this carb or will I need to buy another jet kit. Will it hurt performance at all if jetted correctly? Where is the cheapest place to buy the carb fully assembled or with all the parts and I can assemble it.

[44oEX]

it souldn`t hurt the performance even on non modded quad. we put my 400ex carb on a stock 300ex and it did a big diffrence.

[Metzroth]

k then i think i will look into one. My local dealer (I don't really like) can get me a 450r Carb for $226. Can i get one cheaper than this somewhere?

[khen]

Originally posted by Metzroth
k then i think i will look into one. My local dealer (I don't really like) can get me a 450r Carb for $226. Can i get one cheaper than this somewhere? Yes, buy it from servicehonda.com you can get it for $165. You'll also want to buy the 450R throttle cable and fuel line.

[Metzroth]

Stupid of me but...I can't find the parts on there website. Could you send me a link to it? Also how much are the throttle cable and fuel line?

[44oEX]

I forgot to say that yes the 400ex jet and the 450R jets are the same ( different size but same kind ) so yes your jet kit will work just find.

as for the carb look in the for sale section. you could get a used one for really cheap.

[khen]

Originally posted by Metzroth
Stupid of me but...I can't find the parts on there website. Could you send me a link to it? Also how much are the throttle cable and fuel line? Click on parts at the top of the page and then click on the Interactive Pricing Page link in the middle of the page. You should get a small pop-up page that you can enter the part numbers in and add it to a cart. Click on the OEM Hard Parts link to get to the online parts manuals.

Im with 44oEX though.. you can pick up lightly used carbs for even more of a bargain.

[Metzroth]

well im lookin for a used one. If anyone has one PM me and im interested.

[lelandjf]

Is the carb on the crf450 the same as on the 450r? While searching ebay for a 450r carb, I saw an adapter to put the crf450 carb on the 450r. If this is accurate, would it make sense to put the crf450 carb on a 440ex?

Here is what I saw on ebay:
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&rd=1&item=4536392743&category=43972&sspagename=WDVW

[44oEX]

the crf carb is a FCR and the 450R carb it just a kiehin.

The CRF carb would be alot better. But I don't know if the fit would be the same or not. Cause you have to clear the gas tank and stuff.

[yamablaster24]

My friend is selling a brand new stock 450r carb if anyone is interested.

[QuadJunkies]

I get asked about the 450r carb alot.
I thought for awhile, I would post a sticky on this topic so that it may come in handy for others.
Hope this helps :)
Tina

[krt400ex]

Originally posted by khen
Nah, your pictures look good.. I just never take pictures when I do my mods and people always PM me asking for pics. So I thought I'd be proactive this time. :)

I'm excited to hear another performance review of this carb. I was hoping to try mine out this week at the track, but mother nature suprised us with 4-5 inches of snow this morning.. :(



snow sounds good for testing :D

[krt400ex]

Originally posted by khen
You can use the airbox you just have to move it forward about 1". Here's a picture of how I mounted mine for now. I just put a big washer on the existing mount bolt to hold it down.


so how did u move it closer??

[kris_400ex]

what year 450r carb are you guys useing? i know they changed them in 2006 is the older ones better or the newer ones? or it doesn't make a difference?

[44oEX]

the carb used in this post was the 42mm carb, the one on the 04-05, the 39mm FCR carb on the 06-07 would be better, and would probabaly be easyer to make it fit in the intake boots since it's smaller, don't know about the clearance for the gas tank and stuff tho.

[Troy15x]

I know that this is not the 4 sale section but i have a 450r carb and custom adapter for sale for $150 shipped

I will try and get some pictures posted this weekend

We tried different designs but the airboot always fell off on MX
This one works and keeps stk airbox

[44oEX]

if you bore out the boot enought ( with a dremel or something ), make it big enought that the carb can pop right in and not have to be forced on...it will stay on for mx

[adamsortega]

does anyone know about the throttle control position? do i need it?

[44oEX]

if your talking about the trottle position sensor, no you don't need it, just tape off the wirring or the connection

[adamsortega]

does anyone have any suggestions on jetting my new carb?...i ride in nj, ny, and pa...i have a 440 kit, stage 2 hotcams, yoshimura full system, and im riding with no airbox cover...

[44oEX]

probably start around a 180...and go from there, it sould be a good starting point

[QuadJunkies]

Originally posted by adamsortega
does anyone have any suggestions on jetting my new carb?...i ride in nj, ny, and pa...i have a 440 kit, stage 2 hotcams, yoshimura full system, and im riding with no airbox cover...
I run the same, I am jetted at 180 right now,elev 2800ft.

[yfzfelix]

after spending many hours sanding and grinding my carb boot for a 40 mm fcr for my 460ex I wish someone sold an aftermarket boot with a larger ID because I sure would buy it, I could not see the sense of installing a 40 mm carb on a boot with a 38mm hole in it so I had to open it up and man thats alot of work and I'm still not happy with it so I am going to make my own

[44oEX]

well the 450R carb is a 42mm, try to get that to fit lol....it's work, but well worth it in the end.

[Quadjunkie]

Would this upgrade still apply if you don't have the 440 kit? I like the idea, ie more air and fuel, sounds great.

[j450rking]

Originally posted by QuadJunkies
well, so much for testing out my carb tomorrow.. I blew a head gasket while jetting.....It hasnt ran good during a race and had a weird noise, now we know what the other noise was..... :rolleyes: :mad: Im not sure if its due to a bad jug or the Gasket ect.... We may go back and just put my 426 back on...:( I was REALLY looking forward to trying the 440 too...:ermm:


how dose the 426 compare to the 440?

[44oEX]

Originally posted by Quadjunkie
Would this upgrade still apply if you don't have the 440 kit? I like the idea, ie more air and fuel, sounds great.


yeah it would still help the motor breath better, I had it on my 500ex at first and it really helped, but after I sold the motor I only had a stock bore 400ex and it still help it out.

[Wshunew2004]

Anyone have a 450R Carb for sale ? I'm willing to pay I looked on ebay man but jeeze people are so proud of those things man ?

[44oEX]

I have one...how much you willing to pay for it?

[Wshunew2004]

Well i'm just trying to figure out the best fuel setup on my bike it's pretty much stock other than the cam and exhaust !! So I'm not really sure what are you wanting to get for it ? Around a $100 Bucks or so ?

[44oEX]

you have a PM...nice EX by the way


A 450R carb it a nice upgrade, it will help your motor breath better...and for the price it's a nice investment

[sc400ex_rider]

anyone put a drz400 carb on its a 40mm fcr or a yfz450 carb on. the o6 450r has a fcr now too. 04 04 have the old style.

[dheavychevy38]

I picked up one of these carbs with no cables and ordered the throttle cable but what do i do with the other threaded hole on the other side just plug it or do i have to get some kind of cable for that to Thanks Denny

[dheavychevy38]

I picked up one of these carbs with no cables and ordered the throttle cable but what do i do with the other threaded hole on the other side just plug it or do i have to get some kind of cable for that to Thanks Denny

[dheavychevy38]

I picked up one of these carbs with no cables and ordered the throttle cable but what do i do with the other threaded hole on the other side just plug it or do i have to get some kind of cable for that to Thanks Denny

[hondaracer57]

im pretty sure its for the hot start cable i think u can just plug it cause u dont need it i would just go up to search and type in 450r hotstart and u will find a thread about it...

[44oEX]

No don't just plug it, you need the small plunger that goes inside there, buy a hotstart block off, or just get a 450R hot start cable, when the warm summer weather gets here, you'll be glad you have it.

Still have mine for sale if anyone is looking for one.

[dheavychevy38]

Where can the hot start block off be found i have searched with no luck thanks denny

[44oEX]

I don't know who sells it, I know the YFZ's FCR carbs come with a hotstart block off, It looks the same as the TRX carb hot start, but I don't know if they are the same treads or not

[EXSailor]

does anyone know if the CRF 450r carb is the same? I found one from an 02 real cheap, but I don't want to get it if it won't work.

[EXSailor]

Originally posted by 44oEX
the carb used in this post was the 42mm carb, the one on the 04-05, the 39mm FCR carb on the 06-07 would be better, and would probabaly be easyer to make it fit in the intake boots since it's smaller, don't know about the clearance for the gas tank and stuff tho.

would having the 39mm fcr carb be an improvement? i'm not a great mechanic, if so, why?

[44oEX]

well the TRX 42mm, would be better then the stock ex one, but the FCR would be better then the 42mm yeah, don't know how easy or hard they would be to put on tho.

[EXSailor]

ok, thanks for clarifying, I just read this whole thread yesterday and now i'm seriously considering doing this mod.

[44oEX]

well my carb is still up for sale if your looking for one

[joeb23]

is the throttle sensor needed?

[hondaracer57]

no all the wires hanging off the carb just zip tie them outa the way...

[Hammer trx450r]

I have a stock 450r carb for sale

[joeb23]

Originally posted by hondaracer57
no all the wires hanging off the carb just zip tie them outa the way...
do you know if this would be the same for the crf wiring harness and the 450r carb?

[hondaracer57]

no sorry i have mine on a 400ex but im guessing that ur not gonna need them but y aint u useing the crf carb ive heard they are better cause it it a 39mm FCR...

[joeb23]

I just decided to use the 450r carb it was a little cheaper.

[Quadtrax]

WOW ..... This is the best thread I have ever read. I have a 416 with ported head, full exhaust. This thing has been uncarbed ever since the first bore, (406). I bought two 450R carbs about 6 mo. ago and was worried about the install. I have no doubt this is what I need to make my EX rip. Just to make sure on a couple of things I want to reask a few questions.

1. .. Just bore out the intake?
2. .. I do XC, what jetting do you think? (HMF exhaust)
3. .. I use a 50/50 mix of 112 race gas and 91 pump gas, is this still good mix?

I think this will be enough to get me started. Thank you for all the info in this thread. I'm sure I will have more questions to come.

[hdavis21]

ive got one ont the way lookin forward to gettin it on, but how is it supposed to change the sound? will it have that little whistle out the exhaust that 450's have? might be a DA question just wondering.

[flauge]

To me it had more of that intake sucking sound at idle and a lil more growl at Wot..:cool:

[Got Boost]

how much for that carb? I am interested, 39mm or 41mm?

[krt400ex]

i think that the 450R carb is a 42 millimeter. the '06 and up is a 40

[Hammer trx450r]

True but the 06 is an FCR

[krt400ex]

Originally posted by Hammer trx450r
True but the 06 is an FCR

yes i kno...but believe it or not. i have heard better things about the older carbs on the modded EX's than the FCR's

[Got Boost]

ok how much of a power increase will I gain with 440 kit, 12.5:1 piston, st.2 hc with the 04 carb?

[99426ex]

wassup yall.. just got my 450r carb ($102.00 shipped) getting my throttle cable tomorrow.. just curious if anyone did anything with the heater assy. on the carb.. i went of service honda and checked the exploded view of the carb.. i was wondering if anyone used it or what it's for .. also does anyone use the hotstart cable.. if so how?? where do u hook it up to??.. thanks yall .. good info. all around this forum..

[sc400ex_rider]

the 04-05 450 r carb is 170.00 at service honda. the 06-07 is 800.00 which one do you think is better

[krt400ex]

Originally posted by Got Boost
ok how much of a power increase will I gain with 440 kit, 12.5:1 piston, st.2 hc with the 04 carb?

a rather largely noticeable difference all acrossed the board. this is what i have been told...i have never done it myself.

[flauge]

Originally posted by Got Boost
ok how much of a power increase will I gain with 440 kit, 12.5:1 piston, st.2 hc with the 04 carb? From what Iv'e heard you'll notice more of a gain when you put it on a 440 compared to the smaller bores..You'll be real happy you bought it...:cool:

[Hammer trx450r]

got one! 150 shipped

[400ex124]

could i just snip the wires for the throttle response sensor or whatever its called) off? also can i do the same with the other ther wires on the carb? if not let me know what to do.....plz!!
Thanks Tyler

[44oEX]

yes

[joeb23]

so the 450r throttle cable fits fine in the 400ex throttle box? And what about the hot start how do you hook that up?

[44oEX]

yeah the trottle boxes are all the same on all the sport honda's, as for the hot start, you'll have to get a clutch perch that you can connect it to, or a block off for if if you don't plan on using it. Or you can just hook the cable into it, and if you don't plan on using it, just let the cable loose under your fenders somewheres

[Hammer trx450r]

http://cgi.ebay.com/ebaymotors/2004-Honda-Stock-Carburetor-Carbs-Trx450r-450r-400ex_W0QQcmdZViewItemQQcategoryZ43979QQitemZ28010 0558941QQrdZ1QQsspagenameZWDVW


04 trx450r stock carb WITH BRAND NEW THROTTLE CABLE


EBAY ITEM #280100558941

[wrobben]

so since u can use the stock 400ex jets in a 450r carb, but just diffrent size jets, does that mean that a Dynojet Jet kit for the 400ex would work in the 450r carb?

[KJS]

YES SAME MODEL # FROM THUNDER PRODUCTS

[smartypants]

I have a 42mm carb for sale if anyone is interested, comes with all the jets needed. Send me a PM if interested.

[feelthisroost11]

I have a question..i was looking for a 450r carb for my 440ex and i came across a 03 crf 450 carb and i was wondering if it was a trx related carb? Would it be the same installation as a trx carb?Do i need any adaptors if so? Thanks

[feelthisroost11]

I have a question..i was looking for a 450r carb for my 440ex and i came across a 03 crf 450 carb and i was wondering if it was a trx related carb? Would it be the same installation as a trx carb?Do i need any adaptors if so? Thanks

[QuadJunkies]

Originally posted by Got Boost
ok how much of a power increase will I gain with 440 kit, 12.5:1 piston, st.2 hc with the 04 carb?
I have similar set up. I was told 4 HP gain..
Seems a little on the high side , but I think there was some testing done and thats the numbers it was pulling .
The gains are very noticiable !

[j450rking]

were can i get a hot start block off? or can i just plug the hole? i have seen people just put a plastic plug in the hot start hole. is that ok?

[j450rking]

Originally posted by 44oEX
No don't just plug it, you need the small plunger that goes inside there, buy a hotstart block off, or just get a 450R hot start cable, when the warm summer weather gets here, you'll be glad you have it.

Still have mine for sale if anyone is looking for one.

were can i find a hot start block off? i relly need to know

also what would it do if i just plug the hole?

[honda6490]

Originally posted by QuadJunkies
I have similar set up. I was told 4 HP gain..
Seems a little on the high side , but I think there was some testing done and thats the numbers it was pulling .
The gains are very noticiable !

Definatly get a 11:1 piston, then you can run pump gas if you please.

[Ruby Soho]

if i put a 450r carb on my 440ex, would i notice anything EVEN though i have a stock exhaust? (pipe coming in the future when i can some $$$)

[j450rking]

you should and if you are going to get a pipe later your going to want to get a carb then anyway

[1965 honda]

Originally posted by Ruby Soho
if i put a 450r carb on my 440ex, would i notice anything EVEN though i have a stock exhaust? (pipe coming in the future when i can some $$$)


r you really runnin a stock exfaust on a 440

[Ruby Soho]

yes. bought it like that.

[1965 honda]

thats crazy, i always thought that the was the first mod. but i guess not.

[Ruby Soho]

i would have done a pipe first, but i bought the quad like this. its got no quite core in it with an exhaust tip. so its ALITTLE better than completely stock. but i know an exhaust will really let this thing scream.

so i think im gonna do it considering i can get one for like 50$

[1965 honda]

what are you getting for 50$ i need a knew one mine rotted out for some reason. im having a few problems with mine right know

[Ruby Soho]

i can buy my neighbors stock 450r carb for alittle under 50$

[j450rking]

thats cheap get it !

[Ruby Soho]

im going to get it. but should i put it on before i get the exhaust?

[j450rking]

yeah put it on it won't hurt

[Ruby Soho]

do you think ill notice any gains or better throttle response?

[j450rking]

you should.

have you read any of this thread?

[Ruby Soho]

most of it. but i dont have an exhaust, thats why im asking

[j450rking]

i'm shur it will

[Ruby Soho]

cool, thanks dude

[EX Stud]

hey guys look what i just won on ebay

ebay (http://cgi.ebay.com/ebaymotors/prejetted-keihin-carberater-for-honda-450r-jet-kit_W0QQitemZ280117922549QQihZ018QQcategoryZ43979Q QssPageNameZWDVWQQrdZ1QQcmdZViewItem)

what do you guys think?

do i need to order anything specail for it?

[Ruby Soho]

looks good dude.

question for installation.

if you want to install one on a 400ex, you have to use a drememl and make the boot alittle bigger and then it slips on, then move the airbox back 1 inch. thats all and then i just need to jet it and ride right?

[EX Stud]

i already have my airbox removed anyway...

but do i have to buy a 450r throttle cable?

[dragex400]

Yeah, you need to buy the 450r throttle cable and it fits your throttle on your bars, so you just need the cable. I read posts on here of guys filling the hot start with silicone or putting a bolt in the hot start, that doesn't block it off enough it will still leak air and you'll never get the bog out. IF the carb doesn't come with the hot start cable and you don't want to hook it up, buy the hot start plunger from servicehonda.com and put the plunger in, that will block the hot start off correctly. Also, do not cut or dremel the end of your boot that goes from your carb to your intake ports. If you dremel it or cut the boot it will never seal right. Take some time and force it onto the carb it will go on and it fits really tight but work it on. If this part doesn't seal, again, you never get the bog out and you'll have tons of trouble jetting. For the air intake side, do whatever you can to make it fit right. If you have any problems pm me and I'll help you out. I got mine tuned in perfectly, no bog at all and response is unbelievable.

[j450rking]

how would i tell if i have the hot start plunger or not right now all i can tell is that there is a black plastic peace screwed in to the hole

[dragex400]

The black plastic piece that is screwed in there should be the boot that holds the plunger down. The hot start cable connects to the plunger and when you use the hot start it lifts the plunger. IF the cable didn't come with the carb I doubt that the plunger is in there. To check, unscrew the black plastic piece and see if there is a black cylinder in the bottom of the hole, if there is you can pull it out and look at it, you can pull it with a small pair a needle nose pliers. If it is there you want to pull it out and make sure there is a neopreme ring on it so it seals. If the cable is on it and the plunger is there just snip the cable and leave it in, unless you want to use the hot start, but it is not needed. Also look in the fuel line fitting and see if there is a little mesh screen in there.(looks like a small thimbal). Also you will need a fuel line from a 450r. Your stock 400 fuel line will not work, but the 450r fuel line will fit right on. Also you will have to trim back the yellow choke lever.

[eliasxr400]

Do you think a 450 carb will be worth it with my motor mods?
11.1 std. bore piston, stage 1 hotcam, K&N with air box lid removed, and HMF slip-on.
Also will a Yamaha yzf450 work?

[j450rking]

you should get a good jump

[PinkRider]

I have a 2003 400 ex now a 440, and i got the 450r carb, how did you get the carb to work out referring to the connection between the gas tank and carb? I am having a hard time with that one...help please...

[flauge]

Talking about the gas line? I used a small barbed brass fitting... One side thats sized to the 450r line going to the carb, and the other side thats sized for the 400ex goes to the gas tank....You oughta be able to find it at a auto parts store or maybe even Home depot or something...
Nice looking bike btw.:cool:

[dragex400]

Buy the 450 fuel line from http://www.servicehonda.com The part number is 16956-HP1-000. Make sure to send them an email saying that you want them to send this by mail instead of Fed. Ex. Fed. Ex. is 12$ shipping an US Mail is about 2$. The fuel line is formed so it will not kink. The petcock side is small to fit the petcock and the carb side is huge to fit the carb fitting. The fuel line is speacially formed and the 450R has about the same gas tank as the 400. I put a hose clamp on each connection just to be on the safe side. Hope this helps.

[sc400ex_rider]

i just added the 450 carb and its awesome!!!! i used auto 3/8 fuel line, i screwed a (car) spark plug in the hose to open up one end. i used a hose clamp for the tank. i also cut off one barb of the petcock nipple (lol) not sure if it matters. i used a yfz cable put both jam nuts under or inside the carb to get good free play then adjusted it for WOT. for the hot start i tapped the hole that is behind the throttle plate (engine side) and put a allen wrench set screw in the hole. dont tap all the way just half to start it that way it will snug down and use lock tight!!!!! i used a door panel clip with the funny barbs to fiil the hotstart plunger hole, looks stock. also this idles great i can adjust it down to a stall. heard many probs of idling high, might be cable tension or a vaccum leak. running a 160k main stock pilot 2 turns out on mixture. it will stumble if you punch it WOT at idle in neutral. but in gear this thing is great. might try to adjust the mixture or take some accelertor pump out. oh i also cut off the top vent nipple flush where it hits the tank tapped and filled with allen set screw drilled and used the side vent port. otherwise this is a great package check my sig

P.S. nice pink quad

[PinkRider]

thanks guys for all the help!!! Another question, what about the choke lever hitting the 400ex fuel tank petcock??? thanks :)!

[PinkRider]

Okay guys, I have a picture of my problem that way you know what im talkin about... here ya go, hope this helps:)http://i28.photobucket.com/albums/c235/Daniellecheri/DSC03183.jpg

[sc400ex_rider]

the choke lever is going to haft to be removed. you really dont need it just pump it a couple of times to squirt fuel in there. dont forget to grind the lip off the air filter boot in side and bottom rib that hits the subframe. use a beer bottle to enlarge the hole. also move up your air box alittle about 1/4" use a large washer to hold it down and i used a 1/4" x 1/4" piece of vacumm line on the bolt under the washer to keep it sqaure. ;)

[flauge]

We dont need no steenkin choke! Its summertime! :o lol.

When I got my 450 carb it was already set up for a 400. The factory choke lever was taken off and replaced with a thick peice of wire. Looks like the dude clipped a peice off a clotheshanger and shaped it to fit. It works good but I hardly use it tho. Like sc400ex said, just pump it a few times and it'll crank right up.

If i get my camera in sometime this week I'll try to take a few pics. Maybe that'll help a lil :cool:

[zje400ex]

can i put a 450r carb in, or do i need engine mods?

[sc400ex_rider]

cant hurt plus you have full exhaust. just keep adding to your package.

[PinkRider]

Yes flauge pics would help out alot. thanks!

[sc400ex_rider]

heres a good thread with some pics

http://www.exriders.com/vbb/showthread.php?s=&threadid=160988&perpage=13&highlight=mobile%20dyno%20450r%20carb&pagenumber=1

[PinkRider]

Thanks alot for that link, i think ima try to rig something together this weekend! Ill let everyone know how it goes. please more suggestions if any one has any!
:)

[flauge]

Heres a quick pic i took of my choke lever. I'll try to take another one later today from the top of the carb.
http://i201.photobucket.com/albums/aa177/nickvanacore/honda400ex004.jpg the lil metal peice with the rubber at the end is it.

[Got Boost]

ok guys I found a new carb from service honda, $170 and my local shop was $650. I have a few questions, what size is the stock 400 ex carb (mm), and what is the new carb (450 R) in mm? I havent read the thread so what performance gains can I expect, and what do I need to buy other than the carb to make it work? Thanks for the help.

[sc400ex_rider]

here is more pics of the choke lever

http://i140.photobucket.com/albums/r20/starcraftier1/exchoke.jpg
http://i140.photobucket.com/albums/r20/starcraftier1/dsc02175.jpg
http://i140.photobucket.com/albums/r20/starcraftier1/dsc02178.jpg
http://i140.photobucket.com/albums/r20/starcraftier1/carblabeled.jpg
http://i140.photobucket.com/albums/r20/starcraftier1/airbox-1.jpg

[H_W]

Originally posted by Got Boost
ok guys I found a new carb from service honda, $170 and my local shop was $650. I have a few questions, what size is the stock 400 ex carb (mm), and what is the new carb (450 R) in mm? I havent read the thread so what performance gains can I expect, and what do I need to buy other than the carb to make it work? Thanks for the help.

The stock carb on my 400ex was a 36mm and I think the new ones are 38mm, but I am not sure. The 04 -05 450r carb is a 42mm and the 06-and up 450r carb is a 40mm FCR carb. The yfz450 carb is a 39mm FCR carb. FCR carbs are the best performance wise. That is why the crf and yz 450 dirt bikes come stock with FCR carbs. FCR carbs are a little more expensive. I paid right at $440 for mine from C&D Racing. I told them what was all done to my bike and they jetted it for me. When I got it all I had to do was adjust the fuel screw alittle and ride. The carb was the last thing I did to my 400, and let me tell you it was a night and day difference. I was very pleased with the performance.

[2001400ex]

So from the little bit of reading I have done I have gathered that you need a 450R throttle CABLE in order for the 450R carb. to work on a 400EX - correct?

Is that all? I realize there is a choke issue but that is the least of my concerns at the moment.

And isn't there something with the hot-start that we can make work from the 450R carb. onto our 400EXs?

I would read more but this rebuild is wearing me at and I am just too lazy to read through 17 pages! The original poster should edit the first post on how to do a complete conversion. (Just a thought!)

Thank you.

[Sandman69]

It really is that easy. Yes you have to have a new 450R cable ( which I suggest EBAY) and new fuel line and your ready to go. Dont need to worry about the hot start as you dont need to hook it up at all. Just extra wires. That's all I did and works awesome. Well after all the tuning and jetting.

[2001400ex]

Thanks for the reply.

New fuel line for what? That is one thing I do not think I read. What kind of fuel line (400EX? 450R? What?)

[Sandman69]

the fuel line from the pet cock on the gas tank to the carb. you will need to get the 450 fuel line as the stock 35mm doesnt fit. Of course your kit may have come with the new line, mine did not.

[2001400ex]

Ah that fuel line, duh! Mine is sitting in the basement so if it's not in my face right now it's out of sight out of mind. :p

I will be picking up the 450R fuel line shortly then. Thanks!

[phat1478]

is it nessicary to remove the hot start? does anyone know the size of the 450 fuel line

[zrpilot]

No, just plug the hot start hole.

Use the fuel line from the 450R.

[ZJTurbo]

Is it still possible to take the choke off on the 450R carb??

-Ben

[zrpilot]

Originally posted by ZJTurbo
Is it still possible to take the choke off on the 450R carb??

-Ben

the '04-'05 carb does not have a choke that sits in the air stream like the 400EX does, instead it use an enrichment circuit as the choke. So to answer your question, no it is not possible to remove the choke because there is not one to remove!

Good question!

[Brehmmotorsport]

I still have alot of people asking but no clear responses on what size carb to get. I am stock with full exhaust and kandn. will the 42 work good or should i look for a 06 07 year carb.

[44oEX]

Well the 06-07 39mm FCR is better then the older 42mm regular keihin, for any applications...if you can get a FCR go for it.

[05trx400exridr]

I just read through the entire thread but there still seem to be a couple shady areas.....

*Will this help out my stock 400ex if i pick up a white brothers E series full exhaust system?

*Will either the 400ex or 450r pilot jet work for me?

*What about the main jet, will I need something between the 400ex and 450r sizes?

[zrpilot]

Originally posted by 05trx400exridr
I just read through the entire thread but there still seem to be a couple shady areas.....

*Will this help out my stock 400ex if i pick up a white brothers E series full exhaust system?

*Will either the 400ex or 450r pilot jet work for me?

*What about the main jet, will I need something between the 400ex and 450r sizes?

1) yes, especially if future mods are forth coming
2) you might be OK with the stock 450R pilot, I had to go to a 50
3) Mains will be bigger, 165-175...

[Ruby Soho]

on the 450r install, do you have to modify the boot that goes from the engine to the carb?

[zrpilot]

yes it needs to be ground down some.

[thisperishedmin]

my rides got a ported and polished stock carb. my question is...would i see an improvement in performance and/or reliability if i used a 450r carb? Currently, the stock carb choke tends to bounce itself on after a while riding too, which is a bit of a ****in bother to say the least.

Just curious how far off itd be on jetting, if id be loosing power, gaining power, etc.

thanks for any insight!

[thisperishedmin]

my rides got a ported and polished stock carb. my question is...would i see an improvement in performance and/or reliability if i used a 450r carb? Currently, the stock carb choke tends to bounce itself on after a while riding too, which is a bit of a ****in bother to say the least.

Just curious how far off itd be on jetting, if id be loosing power, gaining power, etc.

thanks for any insight!

[zrpilot]

The 450R carb does not have the traditional choke, it uses an enrichment circuit, so should solve that problem.

If you use the 450R carb, it will have to be rejetted.

As far as power goes, I'd guess you wil be gaining.

[Ruby Soho]

zrpilot, i read your thread about the install. but im not quite sure what exactly you did to make it all work out. i understand the hotstart plug and all that but the hole boots and not moving the airbox thing im kinda confused on.. could you explain that alitte better?

[zrpilot]

Originally posted by Ruby Soho
zrpilot, i read your thread about the install. but im not quite sure what exactly you did to make it all work out. i understand the hotstart plug and all that but the hole boots and not moving the airbox thing im kinda confused on.. could you explain that alitte better?

The 450R carb is shorter then the stock carb and the intake and airside of the carb is significantly larger then stock. So it requires air boot modifications and moving the air box forward. My write shows how I used a custom built adapter to minimize both of these issues.

[Ruby Soho]

Originally posted by zrpilot
The 450R carb is shorter then the stock carb and the intake and airside of the carb is significantly larger then stock. So it requires air boot modifications and moving the air box forward. My write shows how I used a custom built adapter to minimize both of these issues.

well see, i knew that its shorter and such, but i didnt understand what your adapter was.. or what it did

[zrpilot]

Just to be clear, my adapter simply lengthened the carb and stepped down the airbox side of the carb for making the airboot fit easier.

So I did not have to move the airbox from its stock mounting location. Also I did not have to heat up the airbox boot to get it to fit.

[Ruby Soho]

ohhh, i understand now.

[dariusld]

Originally posted by Ruby Soho
on the 450r install, do you have to modify the boot that goes from the engine to the carb?

I read you shouldn't or if you do, be careful not to make an air leak.

I have a few questions.

1)The stock airbox and boot should work with the 450r carb right?
2)How hard is it to install?
3)I heard jetting is difficult, anyone have problems?
4)Is it worth the $100 even with just an HMF slip on, and K&N?

[zrpilot]

Originally posted by FoxHondaRider
I have a few questions.

1)The stock airbox and boot should work with the 450r carb right?


Yes, but they will need to modified slightly


Originally posted by FoxHondaRider

2)How hard is it to install?


Not really, see my Write-up (http://www.exriders.com/vbb/showthread.php?s=&threadid=314423)



Originally posted by FoxHondaRider

3)I heard jetting is difficult, anyone have problems?


NO!
There is a lot of help, many people are running them. Plus there is a HUGE sticky devoted just to jetting the 450R carb!!!


Originally posted by FoxHondaRider


4)Is it worth the $100 even with just an HMF slip on, and K&N?


Yes, go for it!

wow thanks for the quick reply and answering all my questions. awesome i'm looking for a carb right now.

[flauge]

No, jetting is'nt hard at all. Just remember to get your pilot set right then work your way from there.;)

[lorenjr83]

I received my 450r carb today. i tore it down to make sure everything was clean and check the jets. It has a 50 pilot and a 155RD main. I have never seen an RD stamped on a jet. what is the RD for. is it a different brand jet?

[dariusld]

Originally posted by lorenjr83
I received my 450r carb today. i tore it down to make sure everything was clean and check the jets. It has a 50 pilot and a 155RD main. I have never seen an RD stamped on a jet. what is the RD for. is it a different brand jet?

1 minute and google came up with this. "RD jets are made by RD Precision. It's an aftermarket jet that is a copy-cat of Keihin. AFAIK they use the same scale as Keihin--they're suppose to be direct copies."

[lorenjr83]

what would you guys recommend for jetting on a 440 with full exhaust and no air box lid with a k&n filter.

[boosted3g]

For you guys looking to do the swap get yourself one of zrpilots adapters. It will look totally stock, like honda designed a 42mm carb to on there. I got one and it only took maybe 3 hours from start to finish. I fired it up on the first try and havent touched a thing. I thought it was a little big but its not, it will have awesome throttle response and this is on a stock bore engine.

[flauge]

How is it with that 52 pilot boosted3g?? Im on 3 turns with my 50 now and its borderline lean with the few mods I've got.. I'm gonna get an HMF pipe soon so I think the 52 will probably be needed then..:scary:

[dick-84]

Where can u buy the zrpilots adapters?

[dick-84]

If i change my piston to 11.1 and port and polish my head put the 450r carb on there what should i run for gas? I am at sealevel.

[boosted3g]

52 works great and im only at 2 turns on the fuel screw. I would go to the 52 that way you still have adjustment with the fuel screw incase it gets cold you can turn it out some.

Talk with zrpilot he is a member here about the adapter. He posted in the thread recently and is always in the 400ex forum.

[zrpilot]

Here is a link to my installation using an adapter.


450R carb install (http://www.exriders.com/vbb/showthread.php?s=&threadid=314423&highlight=my+450r)

Like boosted3g said, makes the carb install alot easier.

PM me if interested in one.

[dick-84]

Thatnks alot. Ill have to look at that when i get time out side of work. They have alot of stuff bolcked so i cant see the pics. :mad:

[damon#6]

y didn't u just cut a bunch of holes in the air box insted of just takein it off then i wouldn't have to tie in down to the frame

[khen]

Originally posted by dick-84
If i change my piston to 11.1 and port and polish my head put the 450r carb on there what should i run for gas? I am at sealevel.

11:1 is always the borderline on race fuel for the 400EX. I rode the dunes hard on premium gas(92 octane) and it pinged badly and ultimately pulled my head studs and I'm at 4k feet. I would run at least 50/50 race gas, or 100 octane.

[flauge]

I went and double checked how many turns out I had on my screw and found that I screwed it out 4 turns and didnt even know it.! Anyway I just got me a 52 pilot. How many turns out would be close to what i had on the 50? Im thinking maybe 1 1/2 or something. And since Im switching from the e series to an hmf slip soon Im thinking about going up a size or two on the main. Im at a 175K now, How's a 178K or 180K sound to yall? I had 10 discs and a quiet core in the eseries and the hmf isnt going to have any q/c. 180K probably is a better starting point, right???

[BigBore24]

ok got my carb installed last night. install went pretty easy but i didnt know not to ream out the boot that goes onto the motor from the carb. i got the carb on there and put the clamp on real tight. the jets in the carb were a Keihn 182 main and a 50 pilot when i bought it so i left it that way for my 440 with below mods. also the needle was in the 4th slot from the top. the problem is the thing idles like crap, it backfires through the exhaust and the carb. when i rev it, it sounds better and it revs up pretty fast but i dont have my thumb throttle yet so i cant ride it yet. any suggestions on the idle and jet suggestions would be appreciated. im gonna test it tonight to see if i have a air leak around the carb to motor boot. i just dont see that carb going in that hole without doing some boring. also the motor seemed to get hotter than it did before. may b lean?

[riderssb250x]

hey guys i got a question i have a 440 bore and baldwin racing port and polished head and i got the 450 carb on it ( i bought the quad like this) and its making like a kinda loud leak noise almost like a pop leak kinda noise so i listened to to the engine and came to fingd out the noise was coming from the carb any of you guys ever have this problem like do your quads make a nosie when its idling with the 450r crd please help me out

[sc400ex_rider]

sounds like a vacuum leak. is it idleing high? make sure your hot start hole is pluged off good.

[REDRIDER312]

just recieved my 450r carb yesterday and installed the adapter i bought from Zrtpilot.....went on easy and looks great.....but what do you do with the electrical connectors coming off the carb ?? just cut them off or what ...........

[zrpilot]

Yep, I cut mine. You could also zip tie them outta the way. Whatever works best for you. They are not needed.

[REDRIDER312]

THANKS ZRPILOT.....and Thanks for the adapter.....It made everything ALOT easier !!!!

[zrpilot]

No problem, enjoy your 400EX with its new power!!!

[REDRIDER312]

Now I need some expert advice on the jetting......

[Ruby Soho]

got a quick question

when reaming out the boot from the engine to the carb, are you suppose to ream out the small ledges, or what.. i dont want to do this wrong...

[zrpilot]

A couple reminders:
1) you have to do some sanding/grinding on the carb and the intake boot. I found that a Dremel with the sanding drum is the best way to do this.
2) You will have to sand the cast ridges on the air boot side of the carb. First use masking tape, tape EVERY opening into the carb to prevent junk from getting into the carb. Then using the Dremel begin sanding these cast ridges. I found it was easiest to go around the surface by letting the dremel "pull" itself around, CAREFUL!!! go slowly and trial fit the adapter. You want a "press" fit of the adapter onto the carb. The more consistent the sanding is around the perimeter the better, in other words try to NOT have high or low spots. Then, using some RTV, apply a light coat on the carb and the adapter and press them together. To do this I used a rag covered bench vise. Let them sit for the RTV to fully cure (overnight) then using a finger nail, remove the excess.
3) You will then have to sand the air boot that is attached to the engine. To do this I think it is easier to remove this from the engine. Again using the Dremel and sanding drum, go slowly around the inside perimeter allowing the sanding drum to pull itself around. Go slowly, trial fitting the carb until you get a snug fit. DO NOT remove all the ridges, just enough so the carb is a snug fit! Be sure to clean this once your done sanding.

My number one recommendation is GO SLOW ON ALL SANDING! I'm sure you will do a FINE job!

[Ruby Soho]

alright thanks zrpilot! your a great help!

i guess ill wait till tommorow night, because my dremel is at my school auto class:p

i should be able to get it done though and ill will update you!

[zrpilot]

Let us know when you get it running!

[400ex28]

what year 450r carb is the best to run?

[zrpilot]

Originally posted by 400ex28
what year 450r carb is the best to run?

For sure the '04-'05!!!!

[saphunt2r]

I have a 416 with a wiseco 11:1 comp, hotcam stage 2, big gun pip, fresh valve job with new valves And a K&N filter with open air box…I have a 450r carb but need a starting point with the jets here in wisconsin...Any help would be great..

[Ruby Soho]

wow!!!!!!

i got my carb on and running


WHAT A DIFFERENCE!!!!!!!

i totally recommend this to ANYONE with an EX

[zrpilot]

Originally posted by Ruby Soho
wow!!!!!!

i got my carb on and running


WHAT A DIFFERENCE!!!!!!!

i totally recommend this to ANYONE with an EX

I'm so glad it worked well for you!

I had the EXACT same comments when put mine on! :macho

[NoRCaL440EX]

Does anyone know how to tell which year of 450r carb it is? I bought mine off Ebay a while ago and forgot what year the guy said it was off. also any good sugestions on which jets/ jet kits to use?

[zrpilot]

Originally posted by NoRCaL440EX
Does anyone know how to tell which year of 450r carb it is? I bought mine off Ebay a while ago and forgot what year the guy said it was off. also any good sugestions on which jets/ jet kits to use?

if the slide is round, then it is an '04-'05 carb.

[NoRCaL440EX]

oh ok good to know, also I just picked up a 99 with a blown motor that had a 39mm FCR carb but when I pulled it off the 2-3" peice the goes in between the plastic intake on the motor and the carb itself to make it long enough I'm guessing was completely stripped where it threads into the carb, I would have liked to see how it worked any idea where to get parts for these carbs?

[zrpilot]

Originally posted by NoRCaL440EX
oh ok good to know, also I just picked up a 99 with a blown motor that had a 39mm FCR carb but when I pulled it off the 2-3" peice the goes in between the plastic intake on the motor and the carb itself to make it long enough I'm guessing was completely stripped where it threads into the carb, I would have liked to see how it worked any idea where to get parts for these carbs?

www.sudco.com

[Ruby Soho]

hey zr, my carb is on and runs good but theres a few problems.

1. it backfires (wouldnt call it backfire.. but theres pressure that pops through the intake system and actually moves the hole assembly) at idle.

2. im not sure what this could be, but when you hit the throttle it idles up but then stays somewhat high idle by itself then eventually goes back down.

3. it pops alot on decel... heres a little video of the popping, and you can tell when im in my yard, im just blipping the throttle the least bit and its all high strung.

<object width="425" height="355"><param name="movie" value="http://www.youtube.com/v/fIF1myS9fyc&hl=en"></param><param name="wmode" value="transparent"></param><embed src="http://www.youtube.com/v/fIF1myS9fyc&hl=en" type="application/x-shockwave-flash" wmode="transparent" width="425" height="355"></embed></object>

[zrpilot]

Originally posted by Ruby Soho
hey zr, my carb is on and runs good but theres a few problems.

1. it backfires (wouldnt call it backfire.. but theres pressure that pops through the intake system and actually moves the hole assembly) at idle.

2. im not sure what this could be, but when you hit the throttle it idles up but then stays somewhat high idle by itself then eventually goes back down.

3. it pops alot on decel... heres a little video of the popping, and you can tell when im in my yard, im just blipping the throttle the least bit and its all high strung.

<object width="425" height="355"><param name="movie" value="http://www.youtube.com/v/fIF1myS9fyc&hl=en"></param><param name="wmode" value="transparent"></param><embed src="http://www.youtube.com/v/fIF1myS9fyc&hl=en" type="application/x-shockwave-flash" wmode="transparent" width="425" height="355"></embed></object>

Back the fuel screw out 1/2 turn.

What jets are you running? Pilot? Needle clip position?

[Ruby Soho]

50 pilot, 185 main

as you can see it doesnt sputter or anyuthing through the gears its super strong the hole way

needle position is stock i think i never checked it

[Ruby Soho]

i adjusted the A/F screw alittle, what a PAIN.

i got it to stop backfiring through the carb but it still pops and backfires alittle, whats everyone else set their screw at?

[bigbryan]

I just installed a 450 carb on my 400 and it run great, i recommend it to every one. what i did is i use a 2in no hub from the carb to the intake and it work great you dont have to cut the carb it fit perfect

[HondaRaceReady]

Ok, I read most of this thread, and this is the only thing I don't understand. Why use a dremel or sandpaper to make the 400ex airboot bigger, why not just use a 450r airboot and make the airbox hole bigger to make it fit? You could even use a 450r air filter for more air flow.

[zrpilot]

Originally posted by HondaRaceReady
Ok, I read most of this thread, and this is the only thing I don't understand. Why use a dremel or sandpaper to make the 400ex airboot bigger, why not just use a 450r airboot and make the airbox hole bigger to make it fit? You could even use a 450r air filter for more air flow.

The air boot between the engine and the carb from a 450R will not fit the 400EX head. And the air boot from a 450R would not fit into the 400EX airbox.....

To many incompatible parts!

[HondaRaceReady]

The air boot between the engine and the carb from a 450R will not fit the 400EX head. And the air boot from a 450R would not fit into the 400EX airbox.....
What if you put sanded the air boot that fits between the 450r carb and 400ex head so that would fit, and you used a 450r air boot that goes from the 450r carb to the 400ex airbox? You could sand the airbox hole to make it fit.

[zrpilot]

I guess, never thought of trying. Just seems nicer and easier to do it like this:

http://i94.photobucket.com/albums/l97/zrpilot/IMG_0603.jpg

[atvhonda-rider]

hey zrpilot, i tried pm'ing you, i may need a 450r carb adapter, got any left? PM please. Thanks -Wes

[zrpilot]

Originally posted by atvhonda-rider
hey zrpilot, i tried pm'ing you, i may need a 450r carb adapter, got any left? PM please. Thanks -Wes

Did not see your PM, sorry. Good news though, I do have a couple adapters left! Price is still $45 shipped. PM me for further details or email at

z r p i l o t @ g m a i l. c o m

Remove spaces.

[pepshocks]

Originally posted by yamablaster24
My friend is selling a brand new stock 450r carb if anyone is interested. will a 04-05 carb work from a 450r? are they fcr's

[zrpilot]

Originally posted by pepshocks
will a 04-05 carb work from a 450r? are they fcr's

Yes and No

[asohagan]

does anyone know of any 450 carbs for sale? i got a 460ex with a stage 3 cam and a ported head still running stock carb and exhaust. i need an exhaust system to if anyone knows of any let me know

[zrpilot]

Originally posted by asohagan
does anyone know of any 450 carbs for sale? i got a 460ex with a stage 3 cam and a ported head still running stock carb and exhaust. i need an exhaust system to if anyone knows of any let me know Go to servicehonda.com. They are $160 NEW.

[HondaRaceReady]

Did not see your PM, sorry. Good news though, I do have a couple adapters left! Price is still $45 shipped. PM me for further details or email at
What are these adapters you're talking about? The tube that goes from the 450r carb to the 400ex head?

[zrpilot]

Originally posted by HondaRaceReady
What are these adapters you're talking about? The tube that goes from the 450r carb to the 400ex head?

The adapter mates the 450R carb to the air box WITHOUT have to re-locate the air box... It also reduces the possibility of ruining the air boot from stretching to fit over carb... Check out my 450R carb install post (http://www.exriders.com/vbb/showthread.php?s=&threadid=314423)

[ben_400ex]

ok guys i'm trying to figure this out and i'm hoping someone here can give me a definite answer.
I got a second hand 450r carb which has nothing in the hotstart hole, no cable or cable adaptor.
can i just seal and plug the hole to make it air tight or do i need to get something else to do it properly?
cheers

[zrpilot]

The ABSOLUTE BEST way to do this is to purchase item number 8 and seal off the opening with RTV after Item 8 is plugging the HOT start hole.

PS: PM answered!

[400exrider_1230]

if you use the same main jet as you used on the stock carb you're not getting as much power as you could if you use a biger main jet









400ex
swing arm skid plate
big gun slip on
k&n air filter
dg front bumper

[mor300ex]

Hello Everyone, my 14 years old son has the 400ex and I've been reading about the 450 carb swap...right now his machine has the FMF PowerBomb header with a White Bros slip-on, aluminum air box and battery has been relocated...so not much for upgrades. If we are going to do this carb swap does the machine need the internal engine upgrades or will the swap work out ok as he's set right now? Thanks for the help!:D
Oh question on a different topic, his negative battery cable keeps frying right at the connection to the battery :mad: Has this happened to anyone else or dos anyone have a suggestion(s) that can resolve this very annoying issue???
Many thanks to all that have advice.

Pic of my son riding Waldon Colorado Sand Dunes

[zrpilot]

Originally posted by mor300ex
Hello Everyone, my 14 years old son has the 400ex and I've been reading about the 450 carb swap...right now his machine has the FMF PowerBomb header with a White Bros slip-on, aluminum air box and battery has been relocated...so not much for upgrades. If we are going to do this carb swap does the machine need the internal engine upgrades or will the swap work out ok as he's set right now? Thanks for the help!:D
Oh question on a different topic, his negative battery cable keeps frying right at the connection to the battery :mad: Has this happened to anyone else or dos anyone have a suggestion(s) that can resolve this very annoying issue???
Many thanks to all that have advice.

Pic of my son riding Waldon Colorado Sand Dunes

Even on a stock 400EX, you will see a nice throttle response and power improvement. Did you happen to read my 405R carb mini how-to thread?

If I were you, I would do this mod on stock machine.