1badzx12r
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Posts: 8321
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posted November 12, 2009 07:53 PM
Cometic head gaskets
who heres thats had a cometic head gasket leak .. and who here have never had an issue from them ..and do you race your bike .. all my freinds and my self included have had nothing but problems from these gaskets .. mine lasted 20 passes and maybe 200miles
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KZScott
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high on speed
Posts: 7235
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posted November 12, 2009 07:57 PM
never had a problem. 2 yrs my bike with spray(60hp min), 1 with dads
look into lapping your head and block
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01 ZX-12R 8.84 @ 156.3 no bars, DOT tires. Pump Gas, NA.... turbo 8.47 @ 164.
00 ZX-12R 8.62 @ 165.2 no bars, slicks, Pump Gas, 55 shot.... turbo 8.32 @173
00 ZX-12R Fastest NA Kawasaki in the world 1: 222.046 1.5: 226.390 Loring AFB
00 ZX-12R street turbo 1: 227.9 1.5: 234.1 Loring AFB
00 ZX-12R LSR turbo 1: 263.1 1.5: 266.5 Loring AFB Worlds fastest ZX-12R
CMG Racing RCC Turbos
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1badzx12r
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Posts: 8321
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posted November 12, 2009 08:06 PM
it was all fresh decked with a valve job
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dubious
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Needs more time to ride!
Posts: 8442
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posted November 12, 2009 08:26 PM
In the past, on my cars I found copperkote gasket dressing is not good.
started to use hylomar gasket dressing, problems went away...
try that maybe.
Are you stock bore?
One thing I noticed on the zx14 is the combustion chamber is bigger than the cylinder bore, around the valves, exposing the deck, which may cause problems. IMO.
The chamber unshrouds the edge of the deck.
1st time I blow a head gasket, mines gettin oring'd.
I spoke on the phone with Doug Meyer in detail about this and some other stuff.
he did some research, made a few calls and told me that even the prostock zx14, muzzy has not oringed any zx14 motors.... no need being the reason.
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natural selection.....
destiny will overcome intervention.
Some are not worthy of the effort.
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KZScott
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high on speed
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posted November 12, 2009 09:01 PM
block and head were surfaced?
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01 ZX-12R 8.84 @ 156.3 no bars, DOT tires. Pump Gas, NA.... turbo 8.47 @ 164.
00 ZX-12R 8.62 @ 165.2 no bars, slicks, Pump Gas, 55 shot.... turbo 8.32 @173
00 ZX-12R Fastest NA Kawasaki in the world 1: 222.046 1.5: 226.390 Loring AFB
00 ZX-12R street turbo 1: 227.9 1.5: 234.1 Loring AFB
00 ZX-12R LSR turbo 1: 263.1 1.5: 266.5 Loring AFB Worlds fastest ZX-12R
CMG Racing RCC Turbos
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1badzx12r
Needs a life
Posts: 8321
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posted November 13, 2009 05:00 AM
 Edited By: 1badzx12r on 13 Nov 2009 13:05
head was surfaced .. this is how i ended up with my problem .. did a leak-down test .. valves no hold pressure .. removed head .. sent head to machine shop .. head had pitted seats and installed heavy valve springs .. machinist also shaved off 5 thousands on surface .. retested leak-down with cams out after install on bike everything fine ..install cam ..check valve clearance .. everything fine .. with cometic around 20 passes and leaking head gasket .. my stock head gasket had 400passes ..ive got the two gaskets and compared and the stocker has more meat between cylinders(covers more surface ) and a better ring sealing groove.. I'll never use another cometic after the comparison..and yes i'm stock bore
dub .i used copperkote and never had issue but that's all they sell around this area ..unless i go to the big city.. when i had a motor rebuilt a couple years ago .. the builder had used some type of sealant that formed into a silicone layer on the gasket .. I'd like to find me some of that stuff . but i was told by other builders not to use anything ..because the gasket already coated.. damned if you do and damned if you don't thingy .. but this is also the 1st head gasket i've installed dry ..
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http://www.youtube.com/watch?v=S06nIz4scvI
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KZScott
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high on speed
Posts: 7235
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posted November 13, 2009 06:49 AM
these gaskets are viton coated MLS. mine have gone on dry every time. its gotta be super clean and flat.
where did the cometic fail? the head side, block side, or both?
ive started lapping the block and head for every build now based on what Ive read about Entropys builds
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01 ZX-12R 8.84 @ 156.3 no bars, DOT tires. Pump Gas, NA.... turbo 8.47 @ 164.
00 ZX-12R 8.62 @ 165.2 no bars, slicks, Pump Gas, 55 shot.... turbo 8.32 @173
00 ZX-12R Fastest NA Kawasaki in the world 1: 222.046 1.5: 226.390 Loring AFB
00 ZX-12R street turbo 1: 227.9 1.5: 234.1 Loring AFB
00 ZX-12R LSR turbo 1: 263.1 1.5: 266.5 Loring AFB Worlds fastest ZX-12R
CMG Racing RCC Turbos
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Sticks_n_Stones
Needs a job
Posts: 3930
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posted November 13, 2009 06:52 AM
Cometic's is a HUGE gasket maker in the racing industry: if they got it wrong with there ZX14 gaskets, get the other guys you can find that have also had issues on there bikes with there gaskets and send them a email. I have little doubt they will jump all over the issue and get it remedied to keep there reputation intact! It only takes a handfull of unhappy well known customers to kill a brands standing in the racing community.
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'06 zx14
Muzzy M10/M14
PCIII w/ Muzzy map
Flies out K&N in!
bits n pieces...
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Shane661
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posted November 13, 2009 07:27 AM
Edited By: Shane661 on 13 Nov 2009 15:29
From the Cometic FAQ:
What surface finish is required to us an MLS head gasket?
A surface finish of 50 RA (roughness average) or finer, is recommended for a proper gasket seal. Anything rougher may conflict with the gasket design.
Why does Cometic recommend MLS gaskets to be installed dry?
Cometic Multi-Layer Steel (MLS) head gaskets go on dry because they are coated with a sealant. Each MLS head gasket is coated with a .001" thick viton rubber that is bonded to the outer stainless steel layers. Adding an additional sealer can hinder the performance of an MLS head gasket.
Perhaps the surface finish was not right?
Shane
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1badzx12r
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Posts: 8321
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posted November 13, 2009 09:01 AM
only thing i know is the gasket failed on #4 at the water port by the dowel pin .. and it failed on the space between #3 and 4 leaking compression .. it failed on both sides ... it was installed dry ..surface was clean .... and since it failed and pumped air into my water jacket on #4 causing #4 to run hotter ..the piston also has damage there too.. these things i know and can see .. i can also see that the stock gasket has a better water porting design than the cometic flat design.
its no biggy . thats racing .. but tha gasket was the root to my evils ..
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http://www.youtube.com/watch?v=S06nIz4scvI
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1badzx12r
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posted November 13, 2009 09:01 PM
Edited By: 1badzx12r on 14 Nov 2009 05:04
well no doubt now .. you can pull any piston from a zx14 by removing the oil pan and head and in frame .. #1 will need a wobble socket but the rest are easy and straight shots .. and there's no torquing them you do a 120 degree nut turning torque on the rod bolts
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http://www.youtube.com/watch?v=S06nIz4scvI
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MADNINJASKILLS
Novice Class
Posts: 37
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posted November 14, 2009 09:22 AM
I used them on my turbo Grand Nationals and had some issues with them seeping. I never pushed one out though like a stocker would.
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2008 Atomic silver ZX14
2004 GSXR 1000
1998 Honda Valkyrie
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dubious
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Needs more time to ride!
Posts: 8442
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posted November 14, 2009 09:27 AM
must be interesting getting the rings and piston back in the hole!
Rob, how do you find the time to keep playing with that bike all the time? 
Id be divorced, unemployed, and my children would dis own me!
I am impressed with your tenacity!
____________
natural selection.....
destiny will overcome intervention.
Some are not worthy of the effort.
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1badzx12r
Needs a life
Posts: 8321
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posted November 14, 2009 10:05 AM
dub piston and rings fall into the hole if you have a good ring compressor .. but when it running dub its 1 wicked ride ..so thats why i don't mind working on it .. i even purchased a wreck 1 yesterday with a broken frame .. i'm gonna make a nekked turbo drag bike .. i've done worn out too many well -nuts
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1badzx12r
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Posts: 8321
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posted November 14, 2009 10:09 AM
quote:
I used them on my turbo Grand Nationals and had some issues with them seeping. I never pushed one out though like a stocker would.
you know if i only drag raced my bike i'd never had found the issue with it seeping air into the water jacket .. it took a 30 mile ride to find the issue ..
but i did hear the tone change or hiss out of my pipe at the track when it happen coming back on the return road
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http://www.youtube.com/watch?v=S06nIz4scvI
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bigdtd
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Interceptors
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posted November 15, 2009 10:07 AM
quote:
dub piston and rings fall into the hole if you have a good ring compressor .. but when it running dub its 1 wicked ride ..so thats why i don't mind working on it .. i even purchased a wreck 1 yesterday with a broken frame .. i'm gonna make a nekked turbo drag bike .. i've done worn out too many well -nuts
well nuts on the cheap at desmoparts .com fyi 
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2006 Black ZX-14,6 inches over,16/42, flies out,BMC Street Filter,Brock's Street Meg,Brock's Radial Mount Strap,PClll with Race map,Dynojet LCD w/Techmount, ZX-14 fender eliminator,Pilot Power2CTs,Speedohealer,Pazzo Levers,Cox Radiator Guard, Garmin Nuvi 265WT
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1badzx12r
Needs a life
Posts: 8321
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posted November 16, 2009 05:00 AM
quote:
quote:
.. i even purchased a wreck 1 yesterday with a broken frame .. i'm gonna make a nekked turbo drag bike .. i've done worn out too many well -nuts
well nuts on the cheap at desmoparts .com fyi
when i have the frame welded up ..i'm gonna have the well-nut holes weld fully up .. but thanks i can use the info for my other bike ..
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http://www.youtube.com/watch?v=S06nIz4scvI
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