Big Bore Kit

I just received my ring compressor tool so I'm ready to put the head back togehter. I would like some feedback on the following. I received a base gasket form Pit stop and I think it is paper (green) versus the one I bought from Z1 which was black. Anyway my question is,...getting the black base gasket off was not easy,...should I spray the copper gasket spray on the base gasket (paper/fiber?) prior to installing? I know it should be put on dry but will it not seal as well. I would do this only wiht the idea that it would be easier to take off in the future,...if I ever have to.

Gaskets will stick and harden from heat cycling over time.
If your worried about having it seal with ease of removal
and cleanup you can use 1194 instead. It will also raise the
piston in the bore slightly.


.

I have used copper spray gasket sealer before with good results.

A lot of people seem to like to spray paper gaskets with copper sealer. If I feel a sealer is needed I use engine case sealer. It works great on gaskets to seal them and they generally come off without tearing if you need to pull the cover again for some reason.

Permatex makes a nice product called motoseal that works as good as any OEM case sealer I've ever use...and I've used them all. Price is reasonable as well.

OK,....so I finally took apart the head again and confirmed that the new



pistons were rubbing against the gasket. Has anyone seen this before? I thought the top of the pistons were not supposed to go hogher than the top of the cylinder and therfore would be impossible. See pic.

How far is the piston above the top of deck and what gasket are you using?
You either have really small cams or very deep valve notches, time to start measuring things.

I used a one piece gasket then went to a two piece fiber and both were scraping the pistons. It just sticks out over the top of the cylinder a little bitmaybe 2mm?

Here isa pic

That is just wrong. Are you certain those pistons are the correct ones for your block?
It appears that the piston pin holes are too low in the piston, hence the pistons are raised too high.

:huh: cylinder has been decked or piston pin hole location is wrong/dome cut too high (machining) :ohmy: :ohmy: .
:blink: I'm guessing if it didn't have the problem before the new MTC pistons.......... it's a manufacturing problem if you received the correct piston kit ........... you need to start measuring :blink: you can buy .005, .010 .020 ( you can stack as needed)aluminum or copper base gasket or a spacer plate to restore the cylinder to correct height........close to zero deck on the street should make it a runner....if it can handle the crappy gas :ohmy: :ohmy:


p.s. maybe the piston maker will give you another set if those were machined wrong.......... :whistle:

My 2 cents since this occurred in my first buidl (Wiseco 1015)...

Unless you're the originial owner of this bike, you'll have no way of truly what was done to the old girl after 30 years of previous owners performance builds, head decking, cylinder base machining etc...

As with my Wiseco kit, had to double up the cylinder base gaskets due to MRE over machining the 10,000"... When encountered and measured, found measured in more at 17,000ths... Double up 2 cylinder 20,000ths base gaskets, head decking on the money once torqued down (squish factor ~ 3,000ths).... Then confirm head decking...

Anytime building new performance, must always confirm head decking.... No likey bent valves... :pinch: :whistle:
All gaskets other than head 1 or 2 piece gaskets (go on dry) I've been using K&W copper spray, works well... Or as mentioned by Larry, use case sealer, same results...

Pit Stop Kit, 72mm 1 piece gasket for the 1075cc


Head decking...


Gasket Sealer: Permatex Copper spray


Magic in a can:

JimB wrote: Here isa pic

Attachment kz1kpiston.jpg not found

You might have J model pistons instead of KZ pistons. In any event you need to space the block up. Use a setup like Dave did and get your actual deck height. Order the correct spacer to get to zero.