Hi all. My cousin was having an issue with his sons rappy 80 but we were able to find out what was wrong and I thought I would post this to help others out who might have this issue.
Whenever the quad was steered to the left the engine would rev. It has been doing this for a while so we thought for safety we would try to figure it out. First we disconnected the throttle cable at the handle bars thinking it might be adjusted too tight or something was binding in the cable. We started it and it still reved up while steering. Next we took the intake boot off the carb then turned the handle bar to see if the slide was moving but it was staying still. At this point we were puzzled. Next with the engine running we pushed on the cable where it enters the carb and it would rev. After taking a closer look at the carb the base was broken next to one of the mounting bolts. Why it would rev was because when the handlebars were turned the cable would bind a little pushing on the carb making the carb seperate from the engine causing it to suck more air making it run lean which caused it to rev. We replaced the carb and the issue is gone!
We believe how it got broken was from a possible stick popping up and getting wedged between the ground and the carb. Causing it to crack. We plan on installing a skid plate under the frame which will protect it.