I need help on a 2001 YZ 250F. Its a friends and Im trying to help make it easier to start. I usually work on red bikes... The bike is really hard to start cold. I put a new piston (wiesco). The valves are in good shape and adjusted properely. I completely went through the carb. Fresh gas, timing perfect.It seems like the bike is hard to get kicked through the stroke. We have been finding compression, burping the relief and kicking....When I had the valve train out I checked for rstrictions in the bore and its free but when I torque down the cam holders the cam become slightly stiff to rotation. I am feeling that this is being amplified by the gearing of the cam chain and making it hard to kick over. Any other ideas?