xr650r fmf jetting

Hi guys! Wondering if one of you could help me. I have bought a '03 BRP last month. After uncorking it, I have not been able to make the bike run properly. I live in British Columbia (Canada) :) where the altitude is about 2000 ft above sea level. I have changed the pilot jet from a 65s to 68s. I have replaced the stock manifold. I have moved the clip on the needle to 3rd position and removed the plastic and rubber insert from airbox. I put a FMF pipe (powercore IV Q) Then I replaced the main jet from a 125 to a 170. The bike is fairly easy to start and runs pretty good as long as I dont wack the trottle wide open. If I do so, the bike does not like it and wants to stall. I am pretty sure the bike is too rich but not too sure where to start looking :D. Should I change the main jet for a smaller one or should I play with the needle? I need help.... :D <font color="yellow">

When it comes to off-idle response your most effective weapon is your pilot jet & fuel screw. Your 170 main should be fine. I run my needle in the 4th position not the 3rd, but I have heard from people who run it in the 3rd. I run a 68s in mine also, I simply adjusted the fuel screw till I got the response I wanted. The FMF Q does restrict the exhuast a bit more than the uncorked stocker, you might want to contact FMF for jetting suggestions. I would try to adjust the fuel screw first. Do you have the Honda shop manuel? The routine for proper fuel screw adjustment is in there.

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