Been battling some issues recently with my engines mixture. For whatever reason, the bike will only idle when the fuel mixture is retardedly rich. I bought a bunch of the same kit, and 3 others went together with the carb at stock settings and ran great, just slap on and go. This bike would not idle at all. In order to make it run, I had to take the jet out of a differnt carb (from a grubee engine, which seems to have a larger jet) and set the C clip to the richest setting. This makes the bike run. I did some testing, and moving the clip even one notch leaner would make it stop running. So while it runs well, it has the following problems:
- When I took a look in the piston chamber, the whole thing was 100% caked with black soot and crap. The spark plug is completely fouled, and I can't see it lasting very long.
- The bike runs really jerky..... whenever the throttle isnt wide open the bike jerks pretty violently, even at reasonably high speeds.
- The bike has some issues settling down to a low idle. If I go quick, then pull the clutch, it likes to keep running at a high rpm, until I let the clutch go slightly to give it some resistance. This makes it settle down.
When I had the ORIGINAL jet, and STOCK mixture setting (one from the top) the bike could run, if I were to pedal it REALLY fast and start it with throttle wide open, it would start, and have power only on the top end. As soon as you slowed down for anything, it would die. With this, the problem is definitely entirely on the low end. The bike would idle ONLY when the choke was fully on.
Things I have tried so far:
- I have tried 3 different stock carbs, all exhibit the same problem, so I don't think anything is wrong with the carb itself.
- Tried swapping literally every part of the engine. (Coil, exhaust pipe, spark plug, etc) and nothing improved the situation.
My suspicion.... air leak on the carb intake. I've got an O-ring in there, but it doesn't seem to help much. If I spray it with some chain lube while its running, the idle does rev up a little bit, but not by much. Could a tiny air like this cause such a significant problem? One of the other bikes had a carb come off completely (was still on the intake manifold, but was completely loose) and the bike still ran. We didnt even notice until we returned home from a ride. I will be going to the store tomorrow to grab some of this "Seal-All" stuff people keep talking about. I somehow doubt it will work so I'm tossing all this info up here to see if anyone else has some other suggestions.
Thank you in advance! Everyone on this forum has been super helpful troubleshooting in the past.
Matt
- When I took a look in the piston chamber, the whole thing was 100% caked with black soot and crap. The spark plug is completely fouled, and I can't see it lasting very long.
- The bike runs really jerky..... whenever the throttle isnt wide open the bike jerks pretty violently, even at reasonably high speeds.
- The bike has some issues settling down to a low idle. If I go quick, then pull the clutch, it likes to keep running at a high rpm, until I let the clutch go slightly to give it some resistance. This makes it settle down.
When I had the ORIGINAL jet, and STOCK mixture setting (one from the top) the bike could run, if I were to pedal it REALLY fast and start it with throttle wide open, it would start, and have power only on the top end. As soon as you slowed down for anything, it would die. With this, the problem is definitely entirely on the low end. The bike would idle ONLY when the choke was fully on.
Things I have tried so far:
- I have tried 3 different stock carbs, all exhibit the same problem, so I don't think anything is wrong with the carb itself.
- Tried swapping literally every part of the engine. (Coil, exhaust pipe, spark plug, etc) and nothing improved the situation.
My suspicion.... air leak on the carb intake. I've got an O-ring in there, but it doesn't seem to help much. If I spray it with some chain lube while its running, the idle does rev up a little bit, but not by much. Could a tiny air like this cause such a significant problem? One of the other bikes had a carb come off completely (was still on the intake manifold, but was completely loose) and the bike still ran. We didnt even notice until we returned home from a ride. I will be going to the store tomorrow to grab some of this "Seal-All" stuff people keep talking about. I somehow doubt it will work so I'm tossing all this info up here to see if anyone else has some other suggestions.
Thank you in advance! Everyone on this forum has been super helpful troubleshooting in the past.
Matt