still tuning, but it seems okay so far. I bet some math'd show that stinger a bit longish, pro'ly why it does what it does on the low end. Very conservative motor, E50 50cc hi comp head 15/15 Dello SHA and the pipe. Still breaking in fresh rings so I don't want to flog it at present, but it definitely feels like it'll slap some hills around past 3/4 throttle.