Re: new at this need engine size help
They told you the truth. There are no true 80cc engines. The displacement is measured differently by the manufacturer than we do here. We only consider the bore and stroke. They include the combustion chamber in their calculations for marketing purposes. Your 69 cc engine is identical to what is sold as an 80cc, of which there isn't any.
Install it and have fun. If you need help, we're here with answers.
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