Hi all, my wife and I have a Yamaha Vino 49cc scooter. After a move, my wife could no longer use it, and it was garage kept and unused for four years (it only has 149miles). We purchased a phase I install from provoscooter to boost power so maybe so maybe it could take the hills at our new house. After install, it runs but at around 25mi/hr for me (200lbs) and a little faster for her (115lbs) it falls flat - no power unless you let up off throttle. So far we've drained/replaced gas and engine oil, installed new battery, flushed carb and jets. We had to tweek the throttle screw and another screw by it on the carb (I think it controls airfolw?, it doesn't have a head and goes directly into carb) in order to get it to run after the install. It seems as I loosen the "air" screw the problem get worse, and as I tighten it, the scoot gets to a higher speed before power dies, but even with the screw all the way in it still looses power at the speeds mentioned above. Any suggestions as what we might try to fix this problem?
Thanks in advance,
Joe and Liz