squish or the lack of it

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johnny650
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fanbloodytastic ! 1.1mm Squish ... excellent. I'll run with this and keep a careful eye on the squish over the next 100 miles or so and at re-torquing intervals .

Next job whilst I have the cover off is to fit the manifolds and do a leak down test . Hopefully I won't need to replace the drive or mag seals

Thanks everyone for your interest and suggestions.
if I ever need to remove the cylinder again its going to be engine out and on the bench jobbie. Trying to do this on your hands and knees on the decking is ridiculous at my age lol
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coaster
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Use Three Bond on the base with no gasket and a smear of superglue on the head again with no gasket. You could lap the head on a sheet of wet & dry laid on a sheet of glass first just to make sure it is flat
johnny650
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coaster wrote: Wed Jul 18, 2018 1:18 pm Use Three Bond on the base with no gasket and a smear of superglue on the head again with no gasket. You could lap the head on a sheet of wet & dry laid on a sheet of glass first just to make sure it is flat
I chickened out and used the thin base gasket AND threebond :lol:

I just couldn't face having to take that lot off again if it leaked ....I must have had that damned cylinder on and off a dozen times this past 2 days and its a miracle I've still got some rings.

The cylinder head is not like a standard head. its completely flat with the combustion chamber rebated 1.5mm
The gasket face of the head itself has been machined at some point to make it perpendicular to the cylinder so it has a big rebate one side and none the other side

It would be impossible to lap the head .
I'll try and post an image perhaps you can identify the type of head that came with this kit .
Imagesquish 2 by John, on Flickr
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coaster
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That is lappable but you will need to use a courser emery to start with and then drop to a finer grade to finish off. It will take some time though....or get it skimmed on a lathe.
johnny650
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how would you lap it Coaster ? I can't see how I'd do it.
If you look at the top of the picture of the head you can just make out that the gasket mating surface is recessed by about 1.5mm wheras the bottom of the mating surface is flush so you couldn't lap the mating surface ..only the area surrounding the gasket surface or am I missing something ..?
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