Cometic Gaskets
- Thread starter worntorn
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concours
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I've used them on snowmobile engines many years. www.denniskirk.com sold them back in the late 80's.
Good quality.
Good quality.
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cometic gaskets have a good reputation for sealing heads on autos...especially the mls style. i see from your pics you have purchased a flame ring composite head gasket. i am looking for a norton flame ring head gasket for a 850 commando engine i,m re-doing...but want one that is .020 thick...i have one that is .040 thick ,but want to up my compression a bit. if i may ask is yours .020 or .040 thickness. i can,t seem to find a vendor that sells a .020 thick composite flame ring. i have a .020 thick copper gasket from a member on this site that i will use if i can,t find a composite head gasket ...thanks
robs ss
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So the flame ring head gaskets are also re-usable?
Deets55
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I think the thinnest flame ring head gasket you will find are .040" from AN. Last time I spoke with Cometic they told me that theirs were .042" ( I believe, but definitly thicker than AN's ).
As Glen stated they are re-usable (not sure about the head gasket). I am using their valve cover, base and primary on my MKIII for the last 15k miles and they are still leak proof. That includes multiple uses on the valve cover and primary. If you can find an older NOS AN head gasket they were .030". I contact Cometic by phone because not everyting they offer is on their webpage.
Pete
Is the head gasket marked so you know which way is the Top , are both sides the same?
I have an oil leak from the exhaust rocker cover on the 920. The cover has been made flat but the leak persists.
The surface on the head must be imperfect.
This forced me to get off the pot and finally order up some Cometic gaskets for the Nortons. I'm fairly certain that the Cometic Nitrile gasket will seal the rocker cover.
The rest are just for general replacement with the Nitrile &al Cometics as things are taken apart for various reasons.
I forgot to enquire about trans gaskets. I'll bet they have those too.
As Pete mentioned, their website does not work for the Nortons. Even if you have the correct part number and type that in their search box, it comes up nada.
Glen
The surface on the head must be imperfect.
This forced me to get off the pot and finally order up some Cometic gaskets for the Nortons. I'm fairly certain that the Cometic Nitrile gasket will seal the rocker cover.
The rest are just for general replacement with the Nitrile &al Cometics as things are taken apart for various reasons.
I forgot to enquire about trans gaskets. I'll bet they have those too.
As Pete mentioned, their website does not work for the Nortons. Even if you have the correct part number and type that in their search box, it comes up nada.
Glen
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Deets55
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Glen,
I'm pretty sure they have gearbox gaskets, and they also have timing cover gaskets. I did not get either because of the thickeness. I would have to re-shim my gear box because it is set up for the paper gaskets. I was worried about the spacing for the oil pump/cover sealing washer on the timing side. One of those "don't break it if it works" situations. I'm sure you will be happy with the valve cover gaskets. Tighten to spec and forget. Move on to the next Dyno Hill testing
Pete
Schwany
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Are the intake manifold gaskets Nitrile and what is the part number for them on your invoice?
Generic to no one in particular regarding head gaskets: According to Dan1950 with the Blue 850 being rebuilt his pulled flame ring measured .034" I think. It was in theory the compressed thickness of .040" AN gasket. No flame ring head gasket for a Norton is reusable. Defeats the purpose and intended design. People that reuse them are tempting fate.
I took one of the old flame rings off last year and it compressed down to .021" with 3 intentional retorques and many checks on the tightness of those head bolts and nuts over the course many years. Can't get them anymore so doesn't help anyone.
Generic to no one in particular regarding head gaskets: According to Dan1950 with the Blue 850 being rebuilt his pulled flame ring measured .034" I think. It was in theory the compressed thickness of .040" AN gasket. No flame ring head gasket for a Norton is reusable. Defeats the purpose and intended design. People that reuse them are tempting fate.
I took one of the old flame rings off last year and it compressed down to .021" with 3 intentional retorques and many checks on the tightness of those head bolts and nuts over the course many years. Can't get them anymore so doesn't help anyone.
The head gasket on the invoice is for a 750. I also have the 850 head gasket part number somewhere.
The Vincent carb gaskets are really Amal. The first order must have been for a Vincent. I use them on all the bikes that have Concentrics fitted.
Glen
The Vincent carb gaskets are really Amal. The first order must have been for a Vincent. I use them on all the bikes that have Concentrics fitted.
Glen
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The silicone gaskets, for the valve covers are reusable and never leak either. I have had some on my bike for about 20,000 miles (12 years) The ones I have are red in colour. They still look like new. I don't think the silicone material would be suitable for many of the other gasket locations though.
Not silly at all, visible orange gaskets look terrible on a Norton
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