Well the 50 isn't mine its the bro in laws but I am starting to feel sorry for him so here it is, its an 86 lt 50 he has put a new piston, rings, plug, carb, and cdi. It has good compression fuel is making it to the cylinder and it has spark why won't this thing start? Is there any common problems on this particular year? I am leaning towards a timing issue but I don't even know what controls the timing. Would someone please help so my niece has something to ride, rather than an ornament in her dads garage.

 

is it getting air? try 2.5 turns out on the screw. On mine I also find that messing with the choke position hepls out if it is being stubborn.

 

I should also say that when he bought it it was running and the kids were riding and it. From what I understand it just died while they were riding. any guesses????

 

Sound like a possible jet being clogged. Take that goofy "piggybacked pilot jet" out. That helps out alot.