well, sadly, can't say the TBS needles made any noticeable difference in the midrange surging, and need to get a little more saddle time before I make a judgement on throttle repsonse (had stock needle with 1 shim) The only other thing I can think of that makes any sense (except for the fact that it seems most pronounced at one speed range, is maybe the chain being unevenly stretched. I'll throw it up on the floor jack in the morning and watch her go round and round and see what gives... Already checked the concentricity of the jackshaft sprocket, it looks good. Well, what the hell, i've already got an 18t on order, maybe a new chain will be next in line! Gee, glad it's only money...
