crf450 carb on a trx450???

[ho416mx]

Anyone ever put the crf450 carb on their trx yet??? If so any tips or tricks on the install & jetting, im thinking about purchasing one & would like some info on it first.
Thanks in advance....

[911]

i've been looking for one. i have heard it is the best performance gaine next to a pipe :muscle: as for jetting? the bike is also a 450 so the jet should be fine. just make sure to turn out the idle mixture screw a little like on the bikes:D

[One_Bad_400]

what would bring the carburation down 2 mm do, what trx carb is 42mm and the crf is 40mm

[chris450R]

it is not that bringing it down 2mm will help. it is because the crf carb is an FCR flatside carb. it basically flows better that the stock trx carb. at full throttle there will not be a noticable difference but at particial throttle the response from the crf carb will be a lot better than the trx carb.

[savage_bob]

I put the fcr on my 450r and think it was worth every penny. It is more responsive to my motor that the stock carb ever was. The biggest and only important factor is that lag... lacking better words, when you drop the throttle. The quad acts instantly.

To install you need an adaptor, check out noss machine www.nossmachine.com & then some simple wiring. The is a faq on another website ( www.trx450r.org ) :macho under the performance faq section.

Good luck if you decide to do it.

ps jetting will be almost the same as what you currently run, at least it was for me.

[R3Concepts]

Everyone of the racers in AZ that has one says its not worth the money. Gain 1 hp and decent throttle response. One of our other DFR riders has a CS pipe, CS 13.8 piston, CS crf carb, no electronics etc etc, and he never pulls my CS piped, jetted, filter bike by more then 1/2 a bike on a holeshot.

[kazpr]

I believe the flywheel conversion would make a bigger difference and not for that much more.

[chris450R]

Originally posted by R3Concepts426ex
by more then 1/2 a bike on a holeshot.

but he still pulls you, in the holehsot. which is a pretty important part of the race.

[trost66]

I talk to sparks and they said to buy the carb before the ignition system. They said the carb would help more for mx.

[trost66]

I put the sparks cam and 13-8-1 piston in and it is like night and day. Have sparks pipe and filter. It was a tremendous gain over stock piston and cam

[R3Concepts]

And the last time Doug Gust pulled the holeshot was?? The holeshot shows who has more motor, not who can corner, brake and jump better.

[chris450R]

ok that really has nothing to do with this discussion. doug dust is a pro rider. he has porbably one of the stongest motors on the track along with all the others. they are pretty much even with everything. it is just all about who gets off the line(reaction time) better not who has more motor. how many times has doug gust not been right there in the front on the holeshot? not in first but second or third. he is just an awesome rider so you really can't compare that to this situation. all i am saying is you friend pulls you on the holeshot regardless if your only a bike length behind he is still pulling you and getting the holeshot over you. meaning that his carb and cam and etc is helping him do that. yeah you only have a pipe and jetted and filter and not far behind but you are still behind. do the same mods as him and be there beside him.

[R3Concepts]

Nah, Im done spending money on my R, and im not going to spend 1500 more to gain 1/2 a bike length. Thats just a waste.

[chris450R]

hey man no hard feelings about all this. i wasn't tryin to rag on you or anything. but the whole thing this thread is about is you can get a crf carb from service honda for like $350 and a nossmachine air side adapter for $65 and have a new carb set up. cam from sevcie honda is only $160 and a piston around $200 and then labor to install it all, unless you do it yourself. that is way under $1500. i mean th CS carb maybe great but it is basically the same the crf carb and for $699.95 that carb ain't worth it, especially when you can get the same results for $415. i mean there are ways to get performance and not spend that kind of money on a motor.

[chris450R]

me all i want to do to my motor now is get a 13:1 piston and an 04 crf cam and be done with it. i don't reallt feel that i need a carb at this point just yet. but i will get one at some point.

[RedRacer44]

Most of MX guys here are buying the crf carb and are loving it, its more or less the same thing Sparks is selling....Sparks just gets to put his name on the product:D

We have seen the best results from the 40mm CRF (FCR) carb as far as throttle response and performance. It really enhances the power from a built motor. I plan on getting one later on this winter. If you're going to build a motor for MX(piston,cam, port work, etc etc) I'd highly suggest getting the FCR carb either from the CRF bike or not.

JH Racing sells the FCR carb kit like Baldwin and Sparks sells for quite a bit cheaper.

[ho416mx]

OK, I found a carb from an 04 crf450, can anyone help me with the jetting, i have the HRC Kit with an HMF slipon. Also can you use the trx450 stock throttle & hot start cables on the crf carb???

[RedRacer44]

You cant use the stock HotStart cable, if I remember correctly. I might have it backwards. I think you have to buy an adapter for the cables and you have to buy an adapter for the carb too.

Call JH Racing at (918) 371-0101. He can tell ya everything ya need to know, ask for Johnny.

[29FTEX]

Originally posted by RedRacer44
You cant use the stock HotStart cable, if I remember correctly. I might have it backwards. I think you have to buy an adapter for the cables and you have to buy an adapter for the carb too.

Call JH Racing at (918) 371-0101. He can tell ya everything ya need to know, ask for Johnny.

The stock hot start cable worked on my 41mm FCR. It could be a tad longer, but it works.

[iceracer65]

[QUOTE]Originally posted by chris450R
[B] he has porbably one of the stongest motors on the track along with all the others.

strongest motor.....buhahaha...the suki was the slowest bike at the gncmx's......its all rider baby

[FatBoy Racing]

I did this swap on mine and noticed a good difference in throttle response. It's definately alot snappier. The only parts I bought were the carb from service honda (from '03 CRF because its slightly cheaper for some reason) and the adapter from NOSS. Everything else was able to be adapted . . . you have to rewire the TPS because the wire colors dont match up -- here's the cross reference;

Pink to Blue
Green to Yellow
Green/Yellow to Black

if you don't get this right, it will run funny. (not haha funny, erratic funny)

Anyways, the difference in response is well worth the swap, and I've yet to fine tune the jetting just yet 'cuz I blew mine up, but that's next once I get it back together.

Have fun!

[kgbg]

Its worth it. Not faster, but alot funner. I used stock cables, and rewired the plug on the CRF crab, so I can still use the quick disconnect for the TPS. I did nto need an adaptor, but I have a different intake and filter.

[Varmit57]

I noticed on Service Honda that the part number on the '03 carb is diffrent then the '04 & "02. Does anyone know what it the diffrence..

I have a lot of freinds that are telling me that I won't regret it.... I ordered the Noss adapter and a "04 Carb... Well see how it goes....

[brandonpeake]

im interested in this not for HP gains but if the fcr will help the trx450R anything like a 400ex with being able to lug it and thenbeing able to power out without shifting it is well worht it for me im looking for the throttle response and the torque not the hp gains, this is on my list of next mods with a few other things but i want to see someone with a built motor with one to see if it makes more diff there

[ho416mx]

I got the 04 carb & was just curious as to what jetting I would need to run? I currently have a HMF slipon with the HRC jetting. Anyone have any ideas???

[Varmit57]

Originally posted by ho416mx
I got the 04 carb & was just curious as to what jetting I would need to run? The Problem is that there is no perfect anwser. Even if someone has the exact same quad as you they may need a diffrent Jetting for all kinds of reasons. The best thing to do is check out some of these sites that walk you thru checking it. Try this one for Starters (http://www.cdracingonline.com/id57.htm)

Good Luck!

[Martin Blair]

I would sater maybe 5-10 sizes smaller then you had with stock, the fcr is much more efficent

[bbrad mulvey]

now what about that edelbrock carb that is on the market? is that a fcr carb? is that worth it at all? So where are the best places to purchase the carb from and the adapter just get from noss.
thanks
brad

[R_rocket]

There is an Ebelbrock carb on ebay for $350.00.

[jeepnrocks]

im also curious about the edelbrock. i have also heard of some people boring their fcr's out to 42mm ?