Does anyone know what the standard inlet port size should be?

I think ours may have had some tuning work done because the inlet ports have clearly been machined down by the valve guides.

The ports are 32mm dia. Is this standard?

Regards,

Steve.

:confused:

I came across a site (I think it was Australian) quite a while ago where a bloke went into some detail about the inlet port - including pics and diagrams of work needed to improve the standard port, which he reckoned was very poor as it came from the factory. I know my port could be much improved.

I have tried to find the site again, but couldn't.

I just had another hunt for that site, Steve, without success. It was six months ago or more that I came across it, in the early days of my computer ownership, and I didn't realise how relevant and rare the material was, and that I should make a note of it.

But the gist of it was that the shape of the ports as they come from the factory is not very good. Also, I'd say, there would be some variance from one bike to another - the finishing of the castings would not be very uniform, I think, and I doubt that the size of the port openings would be specified anyway.

There is relevant material on the net - typing 'pantah, heads, ports, inlet', etc, into Google is a start.

I've never done any porting, but I've seen it done. I think the general idea is to eliminate steps, and to try and make the passage as straight as possible.

does it look like this?

Skins,

From your description I did a search on Google. This is an Australian site that may match the site you are referring to, although there are no pictures.



Paul

:confused:

Yeah, thanks Paul. I found that one again myself. I seem to remember seeing drawings or images showing modifications of the port. Perhaps that part was recalled from one of the tuning books I've read.

Have you done any more on your carbs?