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Vespa 400 cylinder compression.. what PSI

Posted by klwinter2 
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Vespa 400 cylinder compression.. what PSI
April 08, 2008 01:22PM
Does anyone know the correct compression reading for a Vespa 400?

Or

What is the reading for your car?

PS I have the lobed pistons. I don't know if that effects the compression reading.


Kenneth Winter
Re: Vespa 400 cylinder compression.. what PSI
April 24, 2008 01:04AM
Ken, The standard compression ratio is 6.4:1. The would put the maximum cylinder pressure at 92 (14.7x6.4). You should get over 85 it you check. Don't know what the lobed pistons do to compression ratio. If you get a low pressure, put a squirt of oil in the cylinder to see if it corrects. I haven't checked mine, the engine runs well so I haven't felt need to. I should check sometime to see what it is. Terry
Re: Vespa 400 cylinder compression.. what PSI
May 14, 2010 03:16AM
nope, i have to ask my friend

Car Detailing Charlotte
704-464-0163
[www.cardetailingcharlotte.com]
Charlotte, NC 28246



Edited 1 time(s). Last edit at 05/14/2010 03:52AM by Charlotte.
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