i was just wondering if anyone has used a fcr carb on their 400ex?? if so, i would like to hear the jetting your using. also, mention the mods on your bike.

 

no one has a fcr carb on their 400ex???

 

Go to EXRiders.com and do a search. There was a good thread on this issue not so long ago.

 

I have a 39fcr on my z-400 all it did was take forever to jet no real performance gains.

 

powroll and sparks both highly recommed the fcr for the 400, but i think that is more for the 440 plus machines.

 

yeah, i know powroll and sparks both highly recommend it. however, it didn't give me many gains either.

i am a member on exriders and no one can really help me out there. most of the people i talk to dont even know this carb has a main air jet or air skrew. the thread doesn't go into the detail i am looking for. i am trying to find info on the main fuel jet, main air jet, fuel skrew position, air skrew position, what needle and in what clip position. also, you can mod the accel pumps on the older fcr's so it won't shoot fuel for a full 4 to 6 seconds after hitting the gas. i hear this is what causes the low to mid bog with this carb. thanks for the suggestions.

 

I had one on my 426, its a nice upgrade. I had a FCR39. I really like it. He who said it took forever to jet and was not a performance gain, obviously does not know what he is doign. Its just as easy to jet as stock, probably easier, espicially easier than the Z400 carb, and the performance is alot better. But if you don't know how to jet, you won't get the performance.......
You can mod the accel pump, by installing a small washer inbetweent he diaphram and the cap. I ran a EMP needle in mine.
As far as jetting, that is almost impossible to tell somebody what to jet their quad at over the internet. You need to ride it, feel what its doing, maybe look at the plug, ect.
I woudl recommend gettign the ZipTy racing air/fuel screw extension, so you can adjust it while its running. Take the time, jet it properly. There is a company , I can't remember what tehy are called, factory something, that makes a cap for the accel pump that leans it out alot. Contact Sudco.

 

i actually have the accel pump modded. i have it so it shoots gas for around .5 to 1.0 seconds instead of the 5 or what ever is stock. yes, it leaned it out a bit.

does the washer serve the same purpose as what i have already modded?? i am just not sure what you are talking about when you say diaphram and cap.

i have two needles on order (one if them is the emp). i also already ordered the adjustable fuel skrew.


does this cap for the accelerator pump serve the same purpose as the washer?? what i did what use a block connector (you can also use an RC car wheel collar) put it on the 3/32 inch shaft that pushes the accel pump down. this is how i shortened the squirt. by the way, i think the new fcr carbs have a diffferent linkage on them. this mod only works on the old fcr carbs from what i hear. i guess the newer ones are more protected from debris on that right side of the carb.

 

KGB actually i do know what i am doing when i first put the fcr on my z i tried every main jet you could think of from 140 to 220 nothing would even make the plug change colors it was not until i added a few more mods that it started to work at all.

 

how does the fcr 40mm work for you?