I have a 1981 TR1. with the old type of head gaskets. They seem fragile and I've been thinking if you could make new ones of massive copper instead? Perhaps they have to be made of the same alloy as the cylinder to expand at the same rate? If the are only about 3-4 mm thick the difference could be neglected - right?

hello Lasse,

I do not think it is totally the gasket materials fault these fail regularly. I have not looked at a TR1 cylinder properly but your pictures shows what I have been told - that the larger cc cylinders had their edges too close to the camchain shaft. This gave the gasket no support from behind as it does in the rest of the cylinder, and this turns into a point of weakness for the head gasket. I was wondering about getting a gasket to work by having something placed back to support the gasket. Huh tho I don't have any idea what! :-?

I've read at the TR1.-site that you can weld a small "wall" to separate the head gasket from the cam chain tunnel. My idea was that if you put in a stronger gasket it would hold anyway -without the support of the welded part.

On the new types (of cylinders)  there are no groves so another option would be to fill the groove by welding and put in a new gasket of the one-piece type. It would add about 1 mm to the height but would it matter??

Lasse wrote:

...  It would add about 1 mm to the height but would it matter??

Definitely as your compression would go to hell if you don't skim the lower end for another milimetre to regain the compression-height!

Best Regards,
Greg

OK. Should I shave it off the top or the base of the cylinder?

Lasse wrote:

I've read at the TR1.-site

Hi Lasse this site or another? I would like to look at the article. My fear would be that the weld would come unstuck somehow if it heated and cooled differently from the surrounding area. Then fall onto the camchain and Kaboom! I was thinking more like having a pin or two drilled into that space.

These new gaskets  - what are they made of? The departure from metal (if they are not metal) is this because the new material is as good as the old gaskets or because the new engine produces less compression and then these lesser demanding materials can be used?

Lasse wrote:

OK. Should I shave it off the top or the base of the cylinder?

Look at a schematic of the barrel - its like most bike barrels and has the sleeve protruding from the base. That would be difficult and costly I think to skim in comparison to the top of the barrel which is flat. I think skimming the top of the barrel or the bottom of the head would be the question. I dont know the answer btw ;)

Bri wrote:

[quote author=Lasse link=1139321092/0#2 date=1139481088]I've read at the TR1.-site

Hi Lasse this site or another? I would like to look at the article. My fear would be that the weld would come unstuck somehow if it heated and cooled differently from the surrounding area. Then fall onto the camchain and Kaboom! I was thinking more like having a pin or two drilled into that space.

These new gaskets  - what are they made of? The departure from metal (if they are not metal) is this because the new material is as good as the old gaskets or because the new engine produces less compression and then these lesser demanding materials can be used?[/quote]

Here is the article (from this site);http://www.tr1.de/tr1/press/motorrad_04-1993/mr-04-1993_pic3.jpg

The old version are made of a composite of asbestos and metal. The new wersion of the cylinders are flat and use ordinary gaskets. I don't know if there are any metal in them.