I aquired another Fa50 - 1987, nice black one with a red seat. Has about 800 miles on it and looks really nice!
Problem is, only goes 20. I cleaned out the carb by taking it all apart and used an air can to all holes, etc. It looked pretty clean already. New spark plug w/correct gap. New gas and oil change. The air mixture screw is 1 3/4 out and the throttle about 3 1/2 out. Starts easily the first time, idles great. Runs fine up to 20 (acceleration just OK) When I give it full throttle after 20, it doesn't bog or slow down, it doesn't do anything. It's like limited somehow, its not screaming and maxing out at 20, it just kinda stops there.
I haven't cooked the muffler but I don't think that's it. Could be wrong. I don't have a compression checker, maybe I should get one?
I have more pics if anyone wants to see em!