Carb tuning

i have an uncorked 2001 xr650r and live at 7000ft.  i just rejetted my carb from a 62 pilot to a 68s a stock  to a hrc needle in the 3rd clip position and a 160 to a 165 main.   i have a fmf powercore 4 with a powerbomb header.  the side panel was cut out but i just got a new one and havent cut it yet.   i based it off the chart.  it currently runs only with the choke on indicating lean conditions.  what would you guys recommend me change to get it running well?

Assuming the bike ran before the re-jet, I don't think the jetting is the problem. You are familiar enough with the bike to know which way is choke on, right? Then there are a few options I can think of, your new pilot jet is plugged, the float level is way low, or the fuel flow is restricted at the petcock-fuel filter-fuel line-float needle. The needle you put in is a B53E? If not, go back to stock till you get one.

What did it run like before the jetting changes.  I have to agree with buzzard, since you are at elevation, added larger jetting, yet what you are saying says a lean condition.  Normally, larger jetting and higher elevation would mean rich conditions.


Do double check the choke.  We all do it and have switched the two around.  Also, make sure the fuel screw on the carb is set correctly, about two turns out.  That can also create a lean condition if unscrewed too far after a rebuild or cleaning.  And check to ensure it is put back in correctly.  Spring slips on first, then the metal washer and then the o-ring.


Keep us informed on what you come up with.

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