OK, Just adjusted the valves on my 02 WR. While in there, I did the WR/YZ exhaust cam timing mod (went from 13 chain pins between the cams to 12.) All went well, but now I'm wondering if I have to re-jet. Acceleration is powerful and hard hitting in the mid to upper range of the powerband, but I'm getting alot of popping and backfiring upon deceleration. Is this something that can be adjusted by adjusting the fuel screw a turn or two, or do I need to look to re-jet the pilot and/or needle position? The bike does not seem to be running lean or hot other than the backfiring upon decel. Any advice would be helpful. Thanks.