I have a 1999 YZ400F. Overall, the bike is great but has a few minor annoyances that I'd like to fix. I ride the bike in tight/sandy trails in Michigan for the most part. 1. The bike starts and idles well for the most part when cold, but often doesn't want to idle after it gets hot. I've tried to play with the idle adjusting knob on the side of the carburator while in the field, but found that the bike is very sensitive to any changes. The bike will idle when hot with the choke knob pulled out, but idles very high. Any suggestions on how to best attack this problem? 2. I am currently running a 14/51 final drive ratio, which helped on the tight trails. I still think that I'd like to try adding some weight to the flywheel. Any suggestions regarding the amount of weight? Any suggestions on where to purchase the weights (I haven't found them on TT yet)? Thanks in advance.