Need help diagnosing a problem.
Problem:
About every second or third time out on the bike, the throttle will just take off and rev to the limit while I'm riding. I roll off the throttle but it has no effect. I have to save myself from crashing by clutching it and hitting the kill switch. This has gotten me into trouble on more than one occassion. I now have no confidence taking the bike out on technical trails (like Moab) for fear of shooting off a cliff.
I know that a piece in the throttle assembly was recalled shortly after the release of the bike. This has been replaced with the correct part. Actually, I have now replaced the ENTIRE throttle assembly and the cable to the carb. Basically, everything is brand new between my hand and the carb. Problem has not gone away.
I know that a vacuum leak can cause the bike to idle high. But can it cause an intermittent high rev that can't be controlled by rolling off the throttle?
I replaced the reeds last week and thoroughly cleaned the reed block and mounting surface while doing so. Problem has not gone away. I'm going to inspect the reed block surface one more time to make sure it's not warped.
Anything else I should be looking at? Maybe a spring malfunction inside the carb (carb has been thoroughly cleaned)?
What's the best way to track down a vacuum leak?
About ready to give up on this basket case before I become one...
BTW, I should clarify that I would not put this in the "surging" category. It is more like a full-tilt "pinned". With no way to control it except hitting the kill switch.
Problem:
About every second or third time out on the bike, the throttle will just take off and rev to the limit while I'm riding. I roll off the throttle but it has no effect. I have to save myself from crashing by clutching it and hitting the kill switch. This has gotten me into trouble on more than one occassion. I now have no confidence taking the bike out on technical trails (like Moab) for fear of shooting off a cliff.
I know that a piece in the throttle assembly was recalled shortly after the release of the bike. This has been replaced with the correct part. Actually, I have now replaced the ENTIRE throttle assembly and the cable to the carb. Basically, everything is brand new between my hand and the carb. Problem has not gone away.
I know that a vacuum leak can cause the bike to idle high. But can it cause an intermittent high rev that can't be controlled by rolling off the throttle?
I replaced the reeds last week and thoroughly cleaned the reed block and mounting surface while doing so. Problem has not gone away. I'm going to inspect the reed block surface one more time to make sure it's not warped.
Anything else I should be looking at? Maybe a spring malfunction inside the carb (carb has been thoroughly cleaned)?
What's the best way to track down a vacuum leak?
About ready to give up on this basket case before I become one...
BTW, I should clarify that I would not put this in the "surging" category. It is more like a full-tilt "pinned". With no way to control it except hitting the kill switch.
Last edited: