Well, the custom cut dome is in the cool head. Another dome customly cut would cost some $$$ if done correctly, and I dont have a reason to spend $50 on a normal 22cc dome. Craig Michaels used to, if not still works for Screamline racing in Vancouver, WA. He used to do all of powersports (Ron's) motors, he was VERY big in making some of the fastest oregon hill shooters in banshee's and 250rs. He also did some of Affordable Performance Racing's motor work but I believe he does not do work any more, or i have heard he only does port work for 'close friends'. My neighbor has a 1986 atc250r with the same exact motor in his, same port work, head, dome, etc, yet he runs a 37 carb on same gas setup as me and easily beats full drag ported LRD 330's.

 

I see. Sounds like he does some good work. Just know that all 330's are not built the same. Especially if LRD is specing them to a 'drag spec!!' I dont think that if you change from a 38 to a 37 you will see a night and day difference. You should look at all of the other differences in setup between your bike and his (i.e. gearing, paddle, tire, weight).

 

Ah well, here are the differences. He is running a narrower 10 paddle ultralight hauler. he does not have the boysen reeds (mine are cr250), He has a +6 swingarm, 37mm carb while mine is a 39mm. Also he weights about half as less as me. I've never raced him because I do not want the humiliation. The guy that owned my bike before me were best buds with my neighbor and no matter how much they raced he ALWAYS lost because of the extra weight of the bike and most likely the gearing/paddles. One thing also on my neighbors atc250r is he has a timing advance and ussually sets that, he gets about 2 more bike lengths on the hill when his bike is running right. Mine runs a little rich to be safe.