a - recently i changed the back tire on my '78 columbia and i feel the chain is too loose now that i've put it all back on. i have the tire pulled back as tight as i can when i tighten the bolts, so i don't know what i can do. the chain is slapping against the body right before it gets near the peddles. i wonder if it always did this and i just started noticing since i messed with it. any ideas?
b - my moped idles fine when it's on the stand and the back tire can spin, but when i'm at a stop, it kills. what should i adjust?
c - sometimes when i try to push the bike while it's not running, the engine will become engaged or, at the very least, the bike tire will not turn. it usually will roll ok when it's cold though. thoughts?