fcr owners!!!!!!!

[randallp1]

i just bought a 39mm fcr and wondering wher will i see most improvements. i have a 426 port pol. st 2 cam. i want to be faster top end wise. im in new orleans, wher do u think i should start as far as jetting.

[zrpilot]

the FCR carb is finicky to tune, but I'd try a 155, 158, or 160 main. the EMR or EMP needle on the 4th notch and a 52 pilot.

Not that you want to hear this, but I could never get rid of a low RPM bog that I had with the FCR. It took a new exhaust system and a 450R carb to solve the problem.

416EX 11:1 Wiseco
HRC cam
Sparks X6 exhaust
Port/polish
450R carb
HD cam Chain
HD head studs
No lid
XC CDI
110 octane

Makes 39HP.... good enough for me!

[drew416ex]

I had a 175-180 main in mine when it was a 416. I also had the needle up on notch (to lower it), and a 52 pilot. It wasnt perfectly jetted, but it was real close. I saw improvements on mine botton - top. You will be happy with it when you get it jetted. Many like zrpilot and others on the forum said it is hard to tune, but it wasnt that bad on mine. But you will be running quit a bit larger jets in it compared to the stock carb.

[JOEX]

I belive there is a part inside the carb that can be replaced to fix this. I don't remember the details but I think Colby at C&D Racing has more info.

I could be thinking of a different carb though...:ermm:

to get rid of that low rpm bog that zrpilot was refering to...drop the leak jet down in size...i am not sure what is stock in the 39 mm, but hondas 40mm on the 450r came with a 70 leak jet...go down to a 55 and that bog will go away

[drew416ex]

NOt all fcr's have that. Mine doesnt have a leak jet

[zrpilot]

Mine did not have a leak jet either. Aftermarket Sudco versions are different then stock versions.

[red_rider38]

On my yz426f there is a mod for the FCR card to get rid of the hesitation. The problem was that the pumper would squirt too much fuel when you cracked the throttle open. You would mod the card to adjust the amount of fuel squirted.