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Workshop => Engine and Bottom End => Topic started by: atvmxr on May 05, 2021, 08:23:04 PM
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Is there a trick to keep plugs tight in a cool head?
New dome, jetting is good, fresh c12 fuel, even tried a b9 range plug. Darn thing keeps backing out after ~10-15 minutes. I feel like I’m way over tightening it.
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I like to actually use a torque wrench to tighten the spark plug. That way I don't over tighten them. So according to the manual it's 11-14 ftlbs.
Loren
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If it was over tightened the threads could be damaged.
Was anything else changed in the engine or just a dome change to the same cc or different?
What ignition are you using?
Joe
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its stock ignition.
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Is there a trick to keep plugs tight in a cool head?
New dome, jetting is good, fresh c12 fuel, even tried a b9 range plug. Darn thing keeps backing out after ~10-15 minutes. I feel like I’m way over tightening it.
Detonation is the only thing that I have found that causes a properly torqued spark plug to back out. If jetting is good, fuel is good, are ALL all of the following components and adjustments good. Combustion chamber shape, combustion chamber volume, piston to head clearance, ignition timing, pipe dimensions, muffler restriction, ports, and engine temperature.
Riding style: throttle position vs engine RPM can cause severe detonation even when all of the above components or adjustments are good on highly developed two strokes. Highly developed two strokes cannot be ridden like highly developed four strokes at small throttle opening when the engine RPM is high (in the RPM range where the pipe is working really well) without detonation raising it's ugly head.
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What Jerry Said. Detonation will cause a plug to back out.