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MX450
11-13-2009, 08:58 PM
im thinkin about puttin one on my 05.. from what ive read the 07/08 crf450 carbs are the best? are they 41mm? also, does this bolt right up? what about the carb heater and tps? basicllay what all do i need to make this work right?

also does anyone know if the crf450 and crf450X use the same carb?? bc there is one on ebay off a crf450X.....

Butter
11-13-2009, 11:04 PM
I recently did this with some great results even not at 100%. You need a NOSS adapter, or maybe Dasa makes one too? Not sure. But I believe you have to press and/or epoxy the adapter on the carb. Someone who has actually done it will tell you that. I bought mine already done. Another option is to run an '06+ intake. Airbox, filter, etc. That will eliminate the need for the adapter. Also, either you have to heat up and remold the gas tank, or cut the top of the carb in order for it to clear. Mine was cut on the carb. Very cleanly done. After you get it all done, start with some baseline jetting, because the different carb definitely takes a different jet. I had a 195 main in my old '05 carb. I tried that in the FCR and it wanted no parts of it. Now I run a 172. I have an FCR off an '07 TRX, which is a 40mm. Its soooo much better than the stock carb. I don't think you'd notice insane amount of gain through 1mm, but it may be a bit better. Either way, this will give you some idea. The TPS and warmer plug right in. Eastside400 will hopefully come on here and talk you through it. He really helped me with making up my mind on getting and getting it working.

d3ktrix
11-14-2009, 02:18 AM
You won't have any problems with it clearing the gas tank if its a CRF carb. My 07 CRF clears perfect.
Its the 06+ TRX carbs that need the tops trimmed a little.

And I don't think the FCR carbs have the heater plug do they?
Mine only has 1 plug for the TPS.

MX450
11-14-2009, 01:06 PM
so do you guys think the TRX or CRF carb would be better? looks like there is a couple 06+ trx carbs on ebay for about $250.. does it matter if its off of an ER??

d3ktrix
11-14-2009, 03:10 PM
I just prefer the CRF's because u dont have to modify the top at all. I don't know of any performance differences, depending on the year there 1 or 2mm larger. Both can be bored to the same size I think.

eastside 400
11-14-2009, 05:09 PM
CRF's are easier liek said before, FCR carbs do not have a carb heater so those wires dont get hooked up, for the TPS, it is not plug in on the CRF but its easy swap, ill check on the wire matchups but the best way to do it is to remove the terminals from the stock carb so you can use that connector and then put the wires from the FCR into the right slots of the connector for the harness. it makes it like stock instead of splicing all the wire and stuff. i like using the 06 airbox but i have both setups on my bikes, people say that the 05 airbox has better airflow but for MX it doesnt really matter. the 06 is nice because of the huge filters and you dont have to bother with adapters. I would suggest sending it out and getting it bored also, you can do 42 or 42.5 on a stock venturi and then larger with aftermarket venturis, Mad Brothers Racing did mine and jetted it and it is perfect, starts easier then any other one ive had and power is awesome. also there is some mods to be done to get rid of the off idle bog that all FCR's have, dont waste your money on a quickshot or anything, there is a free mod you can do that 100% gets rid of it and its easy.

Butter
11-14-2009, 05:45 PM
Well, I was no where close, lol. I do know it helps a ton with power, and even the mods needed to make it fit are extremely easy. I got lucky and got an '07 TRX FCR with the adapter for $175. So search around a bit before you buy. Deals are out there. Check TRX450R.org. Seems to be more performance stuff than suspension on there. Good luck.

MX450
11-14-2009, 09:20 PM
well im prob not gonna get it bored out or anything, just want something i can bolt up with minor adjustments. i guess jetting is gonna be fun to figure out.

anyone know if a crf450x carb is the same thing?

mpblaster287
01-07-2010, 07:08 PM
bump ttt

im also interested in what all it takes to make the fcr carbs fit. I have an 04 trx, anyone else have any info or a how to install guide from someone thats done this would be great. thanks

Scro
01-07-2010, 08:21 PM
Baldwin's FCR carb is a direct bolt-on, and has the TPS already wired in...if you wanted to spend a little extra dough.

pro-rider46
01-08-2010, 12:23 PM
if you find a fcr thats unmodified for a 04/05 450r, you will need to buy a noss machine adapter, or the dasa ratpack adapter. you will need to tape up the openings on the carb, and take a dremel or something and grind the little ridge on the outside of the carbs inlet. then you can expoxy the adapter on. i used expoxy, but i had issues with it holding, and eventually jb welded it on there. my air boot and filter fell off of it while racing so thats why i did that. once your adapter is on, you can hook it all up. if you choose to use your tps, look up a cross reference on here, or another forum. then just splice it together, and you should be set to go. if you can find a yfz fcr carb, buy it, you dont have to chop the top off them like you do to the 06+ trx carbs, they have aluminum covers, and if you wanted to you can bore them to a 44mm. the fcrs are very good carbs, i barely noticed a difference when i went from a 40mm fcr to a 44mm lectron. sorry if that sounds all jumbled, im tired.

btw butter, glad to see your still happy with the carb.

Butter
01-08-2010, 06:58 PM
Yo Steve! Thanks again man. Def. happy with the carb. Pulled a holeshot in A-class the last MX race of the season (combined B with A) with your carb. Huge improvement. And your install on the adpater and everything was great. Haven't had a single problem with it. Trying a new setup next year. Got a Web 208 cam, with some new valves and springs. Can't wait to get it all together and going!

pro-rider46
01-09-2010, 11:06 AM
Originally posted by Butter
Yo Steve! Thanks again man. Def. happy with the carb. Pulled a holeshot in A-class the last MX race of the season (combined B with A) with your carb. Huge improvement. And your install on the adpater and everything was great. Haven't had a single problem with it. Trying a new setup next year. Got a Web 208 cam, with some new valves and springs. Can't wait to get it all together and going!

dang man! im jealous! i want to get a 208, and go through and redo all my stuff. i guess i better go get a job,lol. you outta pull alot more hole shots with that setup tho!

Butter
01-09-2010, 10:59 PM
I'm hoping man. Just want to stay healthy all year this year. Been out training in this 0 degree weather. Should pay off in the end. Again, gotta stay healthy!

Sorry to hi-jack the thread guys...