Rigid 16H tyre pressures

Hurray! Today I had my first 'proper' ride on my re-commisioned 1937 16H after 8 months ownership. Not restored - seems to be very original and scarcely any wear. It was last taxed in 1961 and been dry stored ever since.

Runs well so far - only done about 15 miles and not gone over 50mph. But it's fun on Surrey lanes. No smoke, not too much noise or vibration although there was a bit of a buzz when I took it to 40mph in second...once or twice. Probably not wise.

I've gone for the 'Speedmaster/SM2' tyre selection route with my rigid rear 1937 16H - don't really want off road treads at both ends. If it isn't the fastest bike on the road it might as well have nice steering...

But what are recommended tyre pressures? Should they be relatively soft with rigid rear?

Roll on a warn dry summer...!

Nice job David.

On my 1937 rigid Inter I run 30psi front and 26 psi rear. I weigh 96kg.

regards

On my nearest equivalent and Speedmaster/SM tyres, I run 25/25 psi. Going to the old tables, for a load of 240lbs on a front wheel (3.25" section) the recommended pressure is 18 psi, for the rear load of 280lbs (3.50" section) 16 psi. That would assume a loaded weight ofbike and rider of 520 lbs. Purely for rim protection on modern day potholes, I would opt for the higher pressures.

There has been a lot of discussion on this point on the WD motorcycles forum with no real conclusion being reached. It depends on whther the Avons are now an old-style tread pattern on a modern carcass or if they have retained the original construction. Tyres in the 1950s had more rigid side walls and did not need such high pressures to retain stability.

Up until the 1970s, the trend was to insist on higher pressures as the tyre designs improved. As an example, Dunlops started off recommending the same pressures for TT100s as they had for the old K70s but by the end of the decade, they were up to around 27/30 on most machines and this advice carried over to the older tyres on the basis that they had an improved internal construction as well. However, contact with Dunlops recently has shown that their technical support people aren't really aware of the previous history and they now suggest referring to manufacturer's handbook which would have us running 17/20 and I'm sure that would compromise stability at normal road speeds.

I run my 16H on 27 / 30 - It is quite hard but the steering is very accurate and predictable.

I'd suggest phoning Avon to see what they say but I think that on a machine like this, it's pretty much something that an experienced rider has to make his own mind up on.