so im new to the game, but picking up things fast. i just got a 1979 puch maxi with a two speed engine. it was running beautifully until the other night when it just kept dying - i checked the spark and carb and idle, all good as far as i can tell.
but when i had it on the kickstand the bike was JUMPING!! it kept jolting forward even as i sat on top of it at a red light, just kept wanting to go forward and then pulled back. i have no idea where to start with this problem, but i really want to fix it -