'00 XR650R backfires, crackles, and pops!

I have a California model XR650R and have made the following adjustments:

1) Removed neccessary airbox baffle

2) Installed Applied emissions block off plate

2) Installed Baja Designs 'Power Up' kit which included replacing:

a. Carb manifold (now unrestricted)

b. Needle (currently set to middle clip position)

c. Main Jet (now at 170)

d. Exhaust baffle (now unrestricted)

The problem, in all gears when I shut down the throttle to decelerate, I get popping, crackling, and backfiring noises. It isn't so much a performance problem as it is really irritating - the bike has great power through all gears; however, I am inclined to think perhaps I am running too rich.

I am hoping someone else has experienced this problem and can document what they did to remedy the situation. This would save me countless carb removal/replacements fiddling around to isolate the fix.

Oh yeah, the fuel mixture screw is set at 1.5 turns out.

Thanks in advance,

Tim Golden

[This message has been edited by tmgolden (edited September 30, 2001).]

Try 3 turns out fuel mixture. What is your pilot jet?

Your problem indicates a lean condition, not a rich one.


My 650 did the same thing. I changed to a 68S pilot jet. The bike starts better and the decell backfires are gone. Be sure you get a "68S".



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