To tame down a pipey powerband, you can turn down the cylinder base to lower port timing, raising it by adding gaskets will only decrease effective stroke, increase trans duration, and make it worse. You have to check squish before you take material off the base to see how much you can get away w/ taking off. It will be kinda hard to get an accurate reading b/c it has a dome piston but you could realistically be around -1mm, but make sure you run good fuel. Also, I did a auto clutch, it was the best mod yet. It drags out the hit from roll on, so you get this longer climb to WOT, it also keeps the kids worrying about riding, and not about shifting. Most of the kids I see riding them leave it in 2nd gear and ring the p*ss out of it anyway. If none of these options sound like where you want to be, you could make a throttle gov out of surgical tubing and insert it inside the cable in the cap. Just a thought, see ya-