Topic: Head skim

[KESH]

Hi to you all, I am new to this site I have two cb750's a K2 and a K3 both retirement projects, have already started on the K2 the problem I have is that it's needs a head skim, does any body know the maximum in thou that can be done without the valves hitting the pistons, one thing I do know is that a standard head gasket is 60 thou thick and a sports type gasket is 20 thou thick (copper),  am I right thinking the difference being 40 thou is acceptable before any  damage  to the head,
I have used an old glass window with some blue and I believe the head requires a 15  thou skim

any advice out there

Kesh

[Don R]

 I recall the later engines had a bit more leeway due to the factory allowing more tolerance to lower compression. I'd say you might check the clearance with some clay and the old gasket. how is the cylinder deck?

[ekpent]

Don't forget to check/modify any dowels also when you skim before closing it up.

[MRieck]

-.015 is a lot of material to clean up a surface....even heavy corrosion and hammer hits. -.006 or -.007 usually takes care of most stuff.
 OEM gasket is about .043 thick with the base gasket .020. You can take .015 off and keep the stock cam/pistons.....those pistons are pretty deep in the holes to begin with.
 I'd recommend a slotted cam sprocket if you take off .015

[KESH]

Hi thank you for your input, have had the Head reground it took 11 Thou to bring it back to level,

Kev