Cylinder Head Replacement

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Mgmark
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Cylinder Head Replacement

Post by Mgmark »

After a nice ride on the 750 at the Deal’s Gap meet, I decided to give the GT some attention and fix some things. The head needs replacing because of some damage it received when it was in storage outside of the bike, JB weld plugged the holes for now.
I have a good clean used head. I remember there was a thread about the cylinder bore centers being out on some replacement head gaskets. Can anyone recommend the best gasket to use?

Thanks
Mark
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tz375
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Re: Cylinder Head Replacement

Post by tz375 »

In my opinion, which is worth every penny you pay for it :roll:, Cometic are the only gaskets to use.

Ask them for 71mm bore. Aftermarket gaskets have 75 or 76mm bores and allow gas to collect in that annular ring and then they blow the gasket out.

The only disadvantage with Cometic gaskets is they stick like crap to a blanket and take a little more work to clean up the faces, but that's because they work.
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Mgmark
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Re: Cylinder Head Replacement

Post by Mgmark »

Thanks for the info. I'll be ordering from Cometic.

Mark
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Mgmark
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Re: Cylinder Head Replacement

Post by Mgmark »

In case anyone needs it, from Cometic:

H1247SP2043F is the composite fiber with steel rings, 71mm bore and .043 thick, and H1247SP1043C, same bore and thickness but in copper.
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Mgmark
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Re: Cylinder Head Replacement

Post by Mgmark »

Mgmark wrote:In case anyone needs it, from Cometic:

H1247SP2043F is the composite fiber with steel rings, 71mm bore and .043 thick, and H1247SP1043C, same bore and thickness but in copper.
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Evans Ward
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Re: Cylinder Head Replacement

Post by Evans Ward »

Saving that info. Thanks Mark! How does the Cometic compare to OEM price wise?
1976 Suzuki GT750 (Maui Blue), 1972 Kawasaki H2 750 Mach IV (Candytone Blue), 1984 Yamaha RZ350 (KRR- Yellow/ Black).
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Mgmark
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Re: Cylinder Head Replacement

Post by Mgmark »

Evans Ward wrote:Saving that info. Thanks Mark! How does the Cometic compare to OEM price wise?
Hey Evans,
I don't know what the oem costs, I didn't look. I know Cometic has the proper bore centers for the cylinders so that where I went. It's a special order so took about 10 days to my door. $69.92 delivered.
I also replaced all the hardware while I was at it.

Mark
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