Author Topic: Piston to bore clearance CB750  (Read 1143 times)

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Offline jonbuoy

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Piston to bore clearance CB750
« on: January 20, 2007, 07:37:45 PM »
Hi Me again..

So stripped the head and barrels off, camshaft and followers look OK, head needs some work but that will be another story.  I am a bit confused by my Haynes manual regarding piston to barrel clearance.  My manual says to put the piston without rings down into the barrel 3/4inch from top  and see if its possible to insert a 0.005 feeler guage between the two - I can a 0.009 is a sliding fit - the wierd thing is I have the same gap all around the piston not just on the thrust side - I can't measure much difference between the thrust and non thrust sides.  I have the same gap at the top and bottom of the bore - I cant feel any ridge between where the piston slides and the virgin part of the bore.  I can see a line a slightly different colour but there doesn't seem to be any wear.  Is my manual leading me the wrong way?  Piston skirts have slight scuff marks on both sides about 3/4 inch wide.

Cheers

John

Offline crazypj

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Re: Piston to bore clearance CB750
« Reply #1 on: January 20, 2007, 08:07:05 PM »
You are measuring at the bottom of the piston skirt? The top(crown) is a lot smalle than cylinder, r until it gets hot
PJ
I fake being smart pretty good
'you can take my word for it or argue until you find out I'm right'

Offline jonbuoy

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Re: Piston to bore clearance CB750
« Reply #2 on: January 20, 2007, 08:12:22 PM »
No I was measuring from the top......  Maybe thats why - I will go and check!

Offline jonbuoy

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Re: Piston to bore clearance CB750
« Reply #3 on: January 20, 2007, 08:21:06 PM »
Mate I owe you a cold one... pistons are sweet!  Newby mistake number one.... 

Cheers

John