426 in my EX

[forum]

I just recentley picked up an 400ex after repeatedly blowing up my 250r and getting sick and tired of 15 year old equipment. I had to mod my 250r roll design a arms to fit on the ex. So now i got an 400ex with durablue axle, front works (sson to get axis full set) with +2+1 roll designs, turf tamers, beadlocks, front radials,itp 190's,air box mod and k&N, and removed the baffle out of the silencer. I have yet to put my 38mm air stryker on it cause im scared about the jetting issue's after it coming off my R. Anyways. I'm fairly happy with the power out of the corners but on the straights im not impressed. I've been looking around the net at egine mods and came to the conclusion. Why spend $3000 on the engine and have it unrealible and still not as fast as a 426 engine. I can get a 426 engine for around 2500$. then spend a little more on an Lt 250r rad to fit in the ex frame and have a custom pipe built. I was just wondering if anybody can help me with this. Is the Lt250r rad the right one or what else can i do. I just don't see the point of spending so much money on an engine with technology from 20 years ago. and then have the prick over heat. thats the only fault with the 400ex. is the engine. other then that i love it. actualy at first i was happy with the power. but people kept killing me on the straights

[400exRacerX]

:huh

Who in the right mind would spend all that money on Roll a arms and then complement them with works shocks????

And I'm not too sure about that 38mm airstryker carb working on your 400.

[cdalejef]

Were using a Walsh rad. on the TRX450F! The stock 250R rad. doesn't cool well enough! Not sure about the LT rad. tho!

[FullBore52]

Two stroke and 4 stroke carbs are two totally different animals...buy a new 4 stroke carb, dont be cheap

[chris29]

Don't get the 425 get the 416. I have had both and not that much noticalbe power. I now have the 425. I recommend you do the 416 because if somthing happens to it like mine did then you can go to a 425.

[400exRacerX]

Hes talking about a yz426f I believe. Not to bore it to a 426.

[forum]

Ok first of all yes. Im talking about a yz426f engine. second of all. Im not cheap. I just told you I don't wanna spend the money on a crap engine. I already have a 38 mm airstryker. the only thing this engine has going for it is the reliability. And yes the airstryker will work just fine and increase power. I personaly don't care if you think it wont. Cause i've seen in done. second off. Ware do you get off telling me im wasteing my money on work shocks with roll designs. You tell me the difference betewn roll design's and a cheap knock off.( other then stronger) I got the roll designs for a good prce so i bought them. And Im soon upgradeing to axis or pep, or mybe elka so shut your hole. The reason i seem so agravated is because i am. Almost everyone that have answered me has been a jerk about it. Is that mybe because im saying the 400ex engine should be in a museum.? ok im taking it a little to far, but it sure isn't 21st century technology. If anybody can help me without critizing and acting like they know everything it would be appriciated
thanks.

[forum]

hey jeff. Do those welsh rads fit someware on a 400ex frame? i don't really wanna spend the money on an aftermarket frame. And do you guys make custom pipes for this conversion. also. do you have any engines for sale? Just figured I'd ask. thanks. Im also thinking about buying a lonestar axle off you cause my durablue is ticking me off lately. Is there anything else i should now before attempting this conversion?

[400exRacerX]

You smell somethin???:confused:



I think I just **** my pants:eek:

[cdalejef]

Originally posted by forum
hey jeff. Do those welsh rads fit someware on a 400ex frame? i don't really wanna spend the money on an aftermarket frame. And do you guys make custom pipes for this conversion. also. do you have any engines for sale? Just figured I'd ask. thanks. Im also thinking about buying a lonestar axle off you cause my durablue is ticking me off lately. Is there anything else i should now before attempting this conversion?
Not sure about the rad in the 400ex frame. Contact Rocky Ridge Racing, he is putting those motors in ex chassis!
Yep we can make the pipe for it! Sorry, we had to buy a new bike to get the motor.

lets see a pic, and its a 250r, u hav to maintince it once in a while, its not 400ex

[trx400ex]

dont do it, i know the 400ex engine feels slow, but when compared side to sdie with a 250r it keeps up well, just spend a little cash on it and it will be fast enough for you, i wouldnt get the yz

[DVS_Freestyler]

ah man you guys are crazy telling hiim not to get the yzf 426 engine. my friend makes kits for them and that damn thing STOCK pulls holeshots in the Pro Am GNC races. if i were you and you have the money i'd hook up with my friend, he custom makes kits that will allow you to install a 426 engine in a stock 400ex frame. pm me if you want me to get ahold of him for ya, he's off working for polaris right now but he keeps in touch when he's not busy. well worth your money!!!!

[Wired]

sorry, PM me if interested about the 426 kit. i was under my brothers name (LBZFreestyler) when i first posted and just realized it.

[forum]

bumb

[dawzie]

We put the YZF in our EX frame. We had East Coast ATV do the job. They had to cut front frame uprights and relocate them so that the rad would fit. The motor is insane power BUT a bear to get started sometimes. We have a Tom Miller 440 stroker for sale. Complete, carb, exhust and CDI box. Cost us over $3000 looking for $2200

[forum]

bumb

Have ya called rocky ridge racing yet???

Here's a link to an article about Ken and his motor chassis conversions,,I think he's the guy you need to talk too..

also his phone number is wrong on the article,,here's his new number.. 270-259-9604

[forum]

Umm wares the link? hahaha. And I have yet to get a email from adam sick. Im in no major worry im just saying.

Thanks everybody for your reply.

sorry dude here it is..:o

http://www.atving.com/editor/racing/feature/techtip/chassis.htm

[400exBro]

i think that the east cost atv has a good deal for the 426 kits aswell as the crf 450 kits..
in a few years, if honda doesn't come out with a biger bore 4 stroke i am sticking a 426 or the new yzf450/crf450 engine in the 400ex frame, and race it.. Canada doesn't have that stupid 440cc limit...
but no one here in canada has done that too, so the power of the engine will blow the comption away, hands down, they won't know what hit em....
so forum you put that engine into your 400, you will have the #1 plate in no time.
have fun
Bro

[forum]

Thanks 400ex bro. Yea up here in Canada there are no limits in the atv classes there arn't enough of us. so there's only atv pro and atv junior. It's actualy kind of neet to see that the top 5 are uauly 400ex's with the expition of james banks that rides a tricked out raptor. But he still blows everyone away on his almost stock 400ex. I was talking to one of his buddies and he said he doesn't like his raptor. the last race james banks ran a tricked out R. I wonder if Jameses sponser liked that haha. Hey 400ex bro. YOu should really start racing. The experince you learn is amazing. In just 4 races i've learned so much. My first race i was finishing around tenth. the last race 3rd. Riding with faster riders really helps. ANd about the 426. Im still looking into the kits. Does anybody no how much they are and what comes in them?? any info will help tons. I can't wait to get the power i need.

[400exBro]

hey forum i am racing next year for sure...........
also you wanna go to moto park the 20th of july........,.,.,.,.,.
me and a couple buddies are going there and want to test out the tracks i have heard they are pro type tracks with huge *** jumps......
have you been.............
lata
Bro

[400exBro]

hey forum have you talked to adam sick yet............


also i found east coast atvs web site with the conversion kit that i was talking about..
Bro

http://www.eastcoastatv.com/400exyzCRF450conversion.htm



http://www.eastcoastatv.com/400exyz426conversion.htm

[forum]

they don't have kits they charge 995.00 plus parts, american.. RIP OFF. I can get the motor mounts and do it myself. for way less. I was like NOOOOOOOOO way when eastcoast emailed me back. WOW over priced. Yea i talked to adam sick along time ago i think i should get back to him. he said his kits should be ready soon. And motopark Is an awsome track. It's truely a motocross track. Yea july 20th sounds good to me but I'll have to get back to you Im not sure if i can yet. Also RJ is a great trck to. but its only open on wedsdays for practice.

[EricB]

if i were you i would strongly look at the CR450F engine, it produces more HP, it still produces more than the new YZ450F. granted the yammy 426 and 450 are good engines, but the CR is just mo betta, plus its a honda =P

[400exBro]

ow, that sucks 1000$ americain is a lot for just that protion of it...

ya i am looking at 20th 21st to go, i am going to the air port on the 20th, so it will be the 21st for sure pending weather man and what they say will go on.... from the pics it sounds like a sweet track...
rj is the one in barrie right???
i get back to you before we head out to see what date and time we are leaving...
you still have the stock 400 engine it, or is it just sitting there with no engine, :D
also can you rent quads there too, cause my dad might rent one from them,?



also about that 450 thing, y not put a yzf 426 bore it to 440 or 450 and you will make more hp and have way more toruque than the crf, the only down side to the yzf is the starting of the big thumper... either way they are both good bikes.
Bro

[forum]

The Yzf is a better engine. and has more HP. ware did you get that info from?? cause it's wrong. Sorry to sound rude. But yea i would prbly rather have a honda engine but there are way more 426's out there and I have acces to a wr400f. Witch is a perfect quad engine. (same as yz426 exept different gear ratio's) I just double checked fmfracing.com for the dyno charts to compare the 426 and cr450.

[400exBro]

who me or him??

if it is me, i just used common sense, 426 bored out to 440 or 450 with cam, pipe, filter etc... will make a lot more hp than the crf 450 engine (bacily stock)

Forum you ever been to walton track, i heard there track is supposed to be rolling and all of natural doubles and crap, i might check that place out soon too....
anyways talk to ya lata
Bro

[airheadedduner]

I heard that the CRF makes more power but I don't think that is true cause I know the YZ is faster. I saw an article about comparing a Houser\Pro-Fab YZ440(overboard) against a CRF440(sleaved down) They where both stock except for cleanup porting and a WB slip on. The YZ would beat the CRF but the honda made more midrange and was easier to ride, and is really easy to start. The CRF's power is like an EX on supersteroids. They where claiming 49rwhp on the CRF and didn't give numbers for the YZ. Between the 2 it is a damn hard choice, but I don't know if I could ride a yamaha. Of course Tim Farr finished 2nd the first time he rode his crf at the opening national.

[NacsRacing400]

The houser pro fab quad was a cr450f, down bored to 440. it wasnt a yzf. I know because i saw the quad last weekend and it is my dream quad(lol). No flaming here, just providing useful info. That quad is sweet though. ANd who cares which one put the most power out, the are both stupid fast. I am planing on doing the conversion this winter. I also contacted east coast about doing it and that is a rip off for that. For that price i would save alittle more and get an aftermarket frame.

[airheadedduner]

They where both Pro-Fab built bikes in the article. I would take the CRF cause it is more ridable and has lots of midrange. Not because it is fast. That bike was tight but thats a lot of cash. I want to go to a thumper for the same reason as forum, my R is a pain to keep runnin and I go through 16 year old frames like there is no tommorow.

[400exBro]

i think that ama might change the 440cc rule back up to 450 because of tim farr and some others than run the crf450 in the nationals...
so if i lived in the states i would wate a year or two and see what come about with this rule,, then you wouldn't have to destorke the 450 to 440...

but in canada there is no rule, so i could stick a freaking street bike engine into my 400 frame and race it....
and yes it is a tufff decision.......
but who cares, if you get #1 plate on a yamaha or a honda, you still have #1 plate, it is 95% rider 5% machine.
Bro

[True rider]

heres what it would look like. I took this off the forum somewhere

[OutlawEX]

That is one fraking bad *** quad ,if its not man i need a fat girl