95 xr 600 carb adjustements- legandary stumble

95 xr 600 with an fmf pipe on it im at right around sea level--- the main is #152-- pilot is #68 and the clip was #3 from the top ,,the plug color is great the kid had a heat range of 6 in there which was way hot i put the 8 it called for--- it has the stumble off idle ,, i know they all do --- yesterday i dropped the clip on the needle down to 4 {this should make it richer right??} semmed to help a little but not much ,, was watching the lovely flames come out the exh.. every so often,, my yzf 400 did it all the time ,,, it seems from what im reading the main is a bit low but the plug looks fine,, its also 80 here so when it gets cooler it will lean out--- choke slighty on just a little bog is gone and runs fine ,, the lid was removed off the top of the filter also,, and any ideas would be great,,, when reved up hard it does blow a little black smoke not much but plug is a nice color,,,,,

help anyone please :applause: i dont want to end up doing an endo in the middle of the woods,, ok when i have the choke on first click the bike runs fine tourqe is amazing and very responsive but i know it will make it suffer on top end ,,, the whole top[ to my airfilter is missing is that part of the "uncorking" process? i know if i cover half of that inlet it would prob run fine but i want to try and compromise between good tourqe and top end,, i dropped the needle 1 clip to #4 the bog was still there and it had a bit of a lag to....

The needle has nothing to do with an off idle stumble. Go with a bigger pilot jet or get a pumper.

off idle stumble is a trait of the XR. Very very hard to remove. It's not jetting.

It's the mass lean out when you bang the throttle hard.

In Australia people have been known to drill a hole in the slide.

I have a 2000 model worked 600 and I just ride the bke smoother. If you anticipate the cough then ride accrodingly.

A pumper carb will I am told eliminate this problem.

i apreciate the responses i know these things have that stumble ,, i had a yzf 400 that was very similar,, i think im going to go up on the main a couple im only running a 152 thats stock and i have an open filter and a free flowing exh..like i said if i put the choke on slighty there is NO bog and it has massive tourqe,, so i think im goignt o leave the pilot alone and go up a couple with the main -,, and if it helps a little thats all i need,, just dont want any unexpected hiccups in the woods,,, i had to learn to ride the yzf once you get used to it its fine,,,

FMF's website says to use a 155-158 main and 68 pilot as your baseline settings. Clip in the fourth groove. Your settings sound pretty close. Dont whack the throttle to quick and have fun.

put in the 158 main in rev's much better seems to start 1st kick-- still has the hesitation but its better i dont know how much bigger to go on the pilot- its got the 68 in there might try that next

I run the following jetting in my XR6 without a problem.

#62 pilot jet (standard)

#155 main jet (1 size up from standard)

needle 3rd clip position from top (standard)

float level 14.5mm (standard)

airscrew 2.5 turns out (standard 2 turns out)

-give these settings a try and see how you go. Cheers,


A Edelbrock pumper would make a big difference... :applause:

put in the 158 and and 4th clip with the fuel screw out 3 that seems to just about do it,, thinking if i go up 1 on the pilot and drop the fuel screw back to 2 that should just about do it,, bike has a ton more tourque and flat spot on bottom is basically gone ,, and it seems to rip up better-- i know i cant really cure the bog with this carb just want to make it more workable and pull steady throughout the powerband

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