Valve holding/measuring collet.

[tonyfoale]

I only asked about the valves because I am restoring a 1920 v twin side valve AJS engine at the moment and I could do with making some new valves, I am not sure of a suitable material and heat treatment requirements for these.

Alan,

Making valves is a serious undertaking. They are subject to high loading and high temps. I am happy to modify valves but I wouldn't make them from scratch. To answer your question there are many different materials used, Titanium for high revving engines, various alloy steels, stainless and inconel are all used. I am not sure about valve manufacturers in the UK but there are a bunch in the US who can make to order or supply blanks or stock. Getting a blank of the right stem diameter and close to head diameter would be a good place to start from, but I think that in your application modifying used valves from something more modern would work out OK. Compared to modern engines yours would be considered light duty although exhaust valves in side valves engines can have a hard time.

Many thanks for the picture links, what an amazing career you have had so far, that hands behind your back BMW seems to have a very interesting front end.

That had a standard BMW front end but there was an added superstructure to set the rake angle close to 15 deg. as part of some experiments on rake angle that I did around the early 1980s. The experiments and results were featured in my books and several magazine articles. The picture that you mention was published in motorcycle magazines around the world at the time. As to my career i don't look backwards, it starts again tomorrow morning. I ain't done yet. I just try to have fun, my father said that I couldn't expect to make a career out of fun, he was wrong.

Also wondering about how the DOHC conversion worked out, are you back to pushrods because of regs?.
Alan

I prepared that engine for the Island but only got to ride it in practice, a head dropped off one of the valves (Cosworth F1 valves????) and made a pretty mess. Up to then it went really well, it had a lot more power. I never had it on a dyno. I got as far as welding the head to re-machine for new valve seats etc. but pressure of other work meant that it never got any further. I still have it and it could be made to run again but you are quite right about restrictive regs.


here are a couple of pix about those steering geometry tests.