Top-End Redo
- baldy110
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Re: Top-End Redo
05 Oct 2019 19:04
I've used a slightly smaller gasket with no ill effects. In fact I'm reusing a one piece Z1900 gasket now with no problems. The one I just ordered is 72mm and is the same as the last one. I replaced it when I installed my new APE studs earlier this year.
You shouldn't have a problem with the OEM one.
Steve
You shouldn't have a problem with the OEM one.
Steve
Z1b1000 1975 Z1b
kzrider.com/forum/11-projects/598262-kz-...-will-it-live#672882
kzrider.com/forum/2-engine/597654-poser?start=240#704229
kzrider.com/forum/11-projects/598262-kz-...-will-it-live#672882
kzrider.com/forum/2-engine/597654-poser?start=240#704229
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Re: Top-End Redo
05 Oct 2019 19:16 - 05 Oct 2019 19:23baldy110 wrote: Don't see why you couldn't use the OEM gasket.
Is it possible Cometic packaged the wrong size head gasket by mistake?
Considering the previous advice from Dave A. (Street Fighter LTD) was so well defined, I am now just a little uncertain about this.

Please view my reply post to Street Fighter LTD on page 3
1982 KZ1100-A2
Last edit: 05 Oct 2019 19:23 by daveo.
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Re: Top-End Redo
06 Oct 2019 05:58 - 06 Oct 2019 06:52daveo wrote:baldy110 wrote: Don't see why you couldn't use the OEM gasket.
Is it possible Cometic packaged the wrong size head gasket by mistake?
Considering the previous advice from Dave A. (Street Fighter LTD) was so well defined, I am now just a little uncertain about this.
Please view my reply post to Street Fighter LTD on page 3
I will always defer to MTC / Joe Hopper / and Cometic
I just try and raise points to be considered .
As a lot of us have many years experience with kaws and hi performance motors you learn never to assume anything during a build
Check everything for proper fit and function . If you dont you may lose a race or a nice expensive street build and my pockets
are not as deep as they used to be .
Just verify with MTC or Joe H that you have the part that matches your application
Dave
Original owner 78 1000 LTD
Mr Turbo Race Kit, MTC 1075 Turbo pistons by PitStop Performance , Falicon Ultra Lite Super Crank, APE everything. Les Holt @ PDM's Billet Goodies . Frame by Chuck Kurzawa @ Logghe Chassis . Deep sump 5qt oil pan. RIP Bill Hahn
Last edit: 06 Oct 2019 06:52 by Street Fighter LTD.
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Re: Top-End Redo
06 Oct 2019 10:11Street Fighter LTD wrote:daveo wrote:baldy110 wrote: Don't see why you couldn't use the OEM gasket.
Is it possible Cometic packaged the wrong size head gasket by mistake?
Considering the previous advice from Dave A. (Street Fighter LTD) was so well defined, I am now just a little uncertain about this.
Please view my reply post to Street Fighter LTD on page 3
I will always defer to MTC / Joe Hopper / and Cometic
I just try and raise points to be considered .
As a lot of us have many years experience with kaws and hi performance motors you learn never to assume anything during a build
Check everything for proper fit and function . If you dont you may lose a race or a nice expensive street build and my pockets
are not as deep as they used to be .
Just verify with MTC or Joe H that you have the part that matches your application
Dave
Thanks Dave, I will definitely check into it.
Unless there is an actual 74mm. two-piece fiber alternative available, I will likely end up using the Genuine Kawasaki head gasket, considering the following information.
Besides having the slightly smaller cylinder opening, the Cometic gasket thickness is .15 to .20mm. thinner than the Kawasaki gasket. That is close to the .005" milled from the head in 2015, so there would be a further increase in compression with the Cometic, which would also bring the valves that much closer again to the pistons.
:huh:
1982 KZ1100-A2
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Re: Top-End Redo
06 Oct 2019 10:33
I have a gpz1100b2 fitted with bathtub head and cams and have the MTC unitrack kit with 17mm wrist pins.Used cometic gaskets supplied without anything taken off piston crowns.I use Dyna 2000 for ignition and have RS34 carbs and bike runs great. have a large oil cooler and use 99 octane fuel here in the UK.
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Re: Top-End Redo
06 Oct 2019 13:00zippy61 wrote: I have a gpz1100b2 fitted with bathtub head and cams and have the MTC unitrack kit with 17mm wrist pins.Used cometic gaskets supplied without anything taken off piston crowns.I use Dyna 2000 for ignition and have RS34 carbs and bike runs great. have a large oil cooler and use 99 octane fuel here in the UK.
Please post a pic of a piston, and a couple or few of your bike?

1982 KZ1100-A2
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Re: Top-End Redo
06 Oct 2019 13:50
Don't have piston pictures as the engine is built.it's the 1135 10.5 -1 compression kit for the unitrack motor.Maybe Joe recommended taking a bit off the crown because you skimmed the head.I'll post a couple pictures of the bike for you in a couple of days, need to use my wife's phone as mine is from the stone age.
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Re: Top-End Redo
07 Oct 2019 08:12
Cometic Technical Service today put a halt to using either one of these gaskets. Said to "definitely use set having 74mm + bore opening for certain, and this set must have been improperly stamped when manufactured."
So, thank you again Dave for pointing this out. I prefer to err on the side of caution.
So, thank you again Dave for pointing this out. I prefer to err on the side of caution.

1982 KZ1100-A2
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Re: Top-End Redo
07 Oct 2019 08:30daveo wrote: Cometic Technical Service today put a halt to using either one of these gaskets. Said to "definitely use set having 74mm + bore opening for certain, and this set must have been improperly stamped when manufactured."
So, thank you again Dave for pointing this out. I prefer to err on the side of caution.
I Hate being right to slow you down , Love it to keep your project bulletproof
Keep up the good work
Dave
Original owner 78 1000 LTD
Mr Turbo Race Kit, MTC 1075 Turbo pistons by PitStop Performance , Falicon Ultra Lite Super Crank, APE everything. Les Holt @ PDM's Billet Goodies . Frame by Chuck Kurzawa @ Logghe Chassis . Deep sump 5qt oil pan. RIP Bill Hahn
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