compression figures, Vitesse 6

[Flemming]

hi

please help me out on this one:

what would be descent compression figures for a Vitesse 6, 52.000 mileage Engine. None reconditioned.

regards Flemming

[andy thompson]

somewhere in the 135 to 160 range... not sure exactly for this model but +/- less than 5~10% between cylinders is a excellent sign and little improvement when bores oiled is another one

[Flemming]

thanks

I suddenly realise  that the figures might be available from the Workshop Manual.

can't wait to measure them out.

Flemming

[JohnD]

Fleming,
As Andy says, the range of pressures you will measure is wide, so wide that they are no guide to the Q. 'How worn is my engine?"
They are wide because a compression guage is not a precision instrument and cannot be calibrated, so that two gauges will give you widely different readings on the same engine.
And also as he says, the value is to see that the cylinders all have more or less the same reading.
If any are low, try the 'oil test'.
A teaspoon or so of oil into the cylinder, and test again.
If the compression rises, then you have a piston rting problem.
If it does not, then a valve is leaking.

John

[Freebird]

I did the oil test on a Kawasaki 750 many many years ago as Nos 1 & 4 were low. They both came up with oil, but the cause eventiually turned out to be the inlet valves held off their seats. A re-shim sorted it out.

Too much oil used me thinks!