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Dommie 99 bore dimensions.

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Re: Dommie 99 bore dimensions.

Posted by ron_tomkins at November 18. 2018

Previously David Cooper wrote:

Hope it all works out, Ron.

I'd just like to correct my previous mail.  I've just dug out a picture of the top of my 88SS barrel.  As you can see, the spigots on the 88 were much wider than the 99.  Almost certainly the same OD.  So Norton created the fragile spigots when they first bored out to make the 600cc bikes, because the OD of the spigot must have remained the same in order to fit the head recess.  So maybe that's why the later bikes lost the spigot.  It saved them from changing the head recess to fit each size of bike when they were making 500 and 600 and 750 at the same time in the early 60's.

Just for fun, the picture also shows a hole in the piston!

(Sorrt for two pics: can't seem to delete..)

Thanks David. Thought that you might be interested to see the style of liner that is being fitted to mine. I bought what I thought were the right liners from Norvil but when I tried to explain to them why they were not suitable for my barrel, they were more interested in defending the authenticity of their liners than helping me to solve my problem. The stance that Norvil took was that Dominator barrels were NEVER counterbored and the spigot of the Norton liner was designed to register on the top of the barrel. It begs the question: why would Westland produce the flanged liner specifically for the Dominator and the Nomad?

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