Piston Rings


I got the new piston on the Cady engine, but it does not have piston rings yet. I tested the pressure inside of the engine by using a pressure gauge hocked up to the spark plug hole. When I measered the pressure it was only about 40LBS. per square inch. Can anyone tell me what the normal amount of pressure should be for this 50cc engine. How much more pressure would piston rings give? And also how much more power? The rings are on the way, but I just want to know what they will do...



Re: Piston Rings

For moped is 90 to 140 lbs !

I hope you are not running it with no rings

Rings are not a fashion item... they are a NECESSITY... you run a chance of damaging the piston if you are running it with no rings... (burning mixture blowing past the piston skirt).

Wait till you get the rings and install them correctly before running it.

How to install them correctly?

Look above

see the word "resources"?

click on that

then click on "articles'

then read "How To Fix Your Moped"

and scroll down for the answers on how to do that stuff

Re: I hope you are not running it with no rings

Rob Gibbons /

woah, dont run it, like fred sed, the piston rings add pressure and that adds to the overall compression of the engine.

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