Banzai7863
New Member
I'm new to the site, so I just wanted to say hello before I jump into my questions. I'm familiar with several contributors work and know if im seeking good advice, this is the place to get it.
All right, with pleasantries out of the way. I have a huasheng 142f with a Grubee 4g belt drive transmission, 10t output and 48t sprocket. This is a new build with approx. 12 hours on the motor.
The motor idles like crap. It surged quite a bit right out of the box, but has gotten worse with time. RPMs fluctuate rather severely and I can also hear it misfiring. I thought it was fuel related so I removed and cleaned the carbs, ditched the stock petcock for a straight fitting and external shutoff. I removed the exhaust box to check for obstructions and all was clear. I did a valve adjustment at my 10 hour oil change. Nothing seemed to make a difference. I have not installed the recommended upgraded spark plug, but I plan on picking one up tomorrow, while I'm out and about.
When it misfires it sounds/feels like something is loose inside the motor. Is it possible it could be the early signs of a rod bolt problems. It almost seems as if the ignition timing is constantly fluctuating from the piston possibly being in a different position on different rotations of the crank. Perhaps from play in the connecting rod? I have also heard mention of flywheel key failure, or perhaps a misaligned magneto.
Has anyone else experienced these symptoms and have a starting point or should I just tear into it and see what an inspection turns up?
Any insight would be greatly appreciated.
All right, with pleasantries out of the way. I have a huasheng 142f with a Grubee 4g belt drive transmission, 10t output and 48t sprocket. This is a new build with approx. 12 hours on the motor.
The motor idles like crap. It surged quite a bit right out of the box, but has gotten worse with time. RPMs fluctuate rather severely and I can also hear it misfiring. I thought it was fuel related so I removed and cleaned the carbs, ditched the stock petcock for a straight fitting and external shutoff. I removed the exhaust box to check for obstructions and all was clear. I did a valve adjustment at my 10 hour oil change. Nothing seemed to make a difference. I have not installed the recommended upgraded spark plug, but I plan on picking one up tomorrow, while I'm out and about.
When it misfires it sounds/feels like something is loose inside the motor. Is it possible it could be the early signs of a rod bolt problems. It almost seems as if the ignition timing is constantly fluctuating from the piston possibly being in a different position on different rotations of the crank. Perhaps from play in the connecting rod? I have also heard mention of flywheel key failure, or perhaps a misaligned magneto.
Has anyone else experienced these symptoms and have a starting point or should I just tear into it and see what an inspection turns up?
Any insight would be greatly appreciated.
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