Cometic gaskets

[scootertramp]

I gotta pull a head to fix the exhaust studs so I'm thinking I should go to .030 Cometics. Heard that that bumps compression or helps squish or something like that. Hoping it'll clear up a little of my pinging below 3000 rpm?

[fathead1550]

It will give you a bit more compression = more pinging.

[Pushrod]

good idea,  Tight squish is better then loose squish,  when you have heads off you could enlarge the combustion chamber to  lower the compression, 
what motor set up do you have now?

[scootertramp]

96" engine. Andrews 37H cams. Thundermax & Rinehart 2:1....Wish I could afford to do the head work now but the only reason I'm pulling the front head is to repair the damn broken exhaust stud! Just dumped a bunch of dough into my hot rod evo so I'm broke. Just figured since I was there I'd replace both head gaskets since I have to do one!

[Hillside Motorcycle]

May want to pull some timing outa' that area where the detonation is occuring.
Scott

[DarrellV]

I used the Cometic .030" HG on my 95" carb. motor. I used flat top pistons and stock 08 heads. But I am getting some ping now myself under load. I'm wondering if I messed up in going with the .030" HG Starting to second guess myself thinking I should have just went stock.

[wfolarry]

Going to a .030 head gasket will not cause a motor to ping, overheat or anything else you might associate it with. Tight squish has it's benefits but if you have a bad tune then nothing's going to cure it but the tune.

[jrussell]

If the OP's 96 is stock and pinging, I'll bet it's all loaded up with carbon. You'll find out soon enough. The broken stud might be the last of your problems, start thinking about guides, seals and rings if it's fouled. It would be a good time to route the crank vent to atmosphere as well.

Don't ya just love a can 'o worms...

[Hillside Motorcycle]

Whole-heartedly agree with Larry's comment.
Scott

[scootertramp]

I can use the .030 cometics with the stock pistons right?

[Pushrod]

of course you can. going to  .030 is a win-win,   
Get it tuned by some one who knows how to tune them,