How to measure if my enigine has been bored over.

Srinath

OK I was thinking of leaning it hard left, putting it @ BDC on right cyl, get both valves closed so its at the bottom of the compression stroke, putting a funnel in the spark plug hole and checking how much fluid fits in the chamber. Yea its too inaccurate to measure 1mm or 2 mm over bores, but it should be easy to find a bigger bore, like say to 700+.

y bike vibrates so much I suspect its got a bore and no rephase. I know its still the 360.
TIA for any ideas.
Cool.
Srinath.

jayel

if you had access to a known 650 you could insert a rod in thru the spark plug hole to the opposite cylnder wall and measure that distance to a known spot on the head (edge of spark plug hole) then take the same measurement on your suspected big bore, again probably to inaccurate to tell exact size but easier than filling your cylinder with oil

Srinath

Well I have that spare 78 sitting round ... I can try it. 5-6mm is a large enough number to see even iwht the most inaccurate dowel.
Yea, I knew someone would come out with a better idea.
Cool.
Srinath.

gggGary · Full Member Joined: Jan 07, 2009 Posts: 114

Hey I am facing the same dilemma I just picked up a 79 special this morning 850 kit he sez, yeah right sez I, but hey maybe it is a 750? A guy can hope right? Anyway I also am going to try to come up with a way short of pulling the head to see how big it is. I do have a stock 82 so that might help. No gasket leaks 8,000 showing on the Odo. This should be the basis of my bobfey bike.

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