piston locks up when going fast

***VANILLA BLUNDER*** /

ive got a 78 puch and when the engine gets hot and im going aroun top speeg, the engine buzzes and locks up.

after a second it starts back up but it sucks and is scary. i just put new piston rigs on so its not that. help!

p.s. it starts and runs awesome other than that

Re: piston locks up when going fast

do you have the air filter on?

are you mixing your gas right?

Re: piston locks up when going fast

Did it do it before you put new rings in?

Re: piston locks up when going fast

See Ya Moped Army /

If you installed new rings, you should have broken them in properly by not exceeding 25mph for the first couple hundred miles. Since you have been running WOT on those new rings, you probably scored up the cylinder, piston and rings and now it's soft-seizing.

Re: piston locks up when going fast

If the piston is seizing, I don't think you would be able to restart the motor?

If the motor did seize, I would take the cylinder head off as soon as possible to inspect the cylinder walls before you go for any long distance riding.

Re: piston locks up when going fast

as a precaution I allways run my fuel mix a little heavy for at least the first tankful for extra lubrication,also it would be interesting to know if you checked your ring gap in the cylinder before installing them.One other thing you may have to check is that the ring gaps are not lined up but staggered

Re: piston locks up when going fast

See Ya Moped Army /

A soft seize is not the same as a full piston seizure when the piston completely locks up. A motor will re-start after a soft seize once it cools down a bit.

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