I have an 01 xr650l w/ 9700 mi. (Motard Trim). 120 front & 160 rear. Lots Of Mods. Here lies the problem, In 1st gear take off the bike seems to skip or something. It feels to me like the back tire would break loose (spin) for a few seconds then grab traction when I let up on the throttle. If I hold the throttle down it will do it continuously (does not sound to good when it does it). I had a friend ride along with me to see if he could tell what the problem could be. Well the tire is not spinning. the tire sidewall has been shaved down to allow clearance for the chain, However it rubs the tire a little. This is not acting as a clutch problem would do this in all gears? I'm hoping this is not a transmission problem. Once I hit 2nd gear it runs great (no problems). Any advice or comments would be greatly appreciated to help troubleshoot this problem. Thanks!!!