Hitchcocks Forum

Hello again, been out for a decent ride today and had the bike cranked over a fair bit on the twisty's , now I am all too aware that this is no sports bike lol but after feeling the bike being a little "choppy" and checking the profile of my back tyre, I noticed it is basically square with corners on it. This means when the bike leans over there is hardly any tread rapping around the sidewalls and I am gripping the road with about an inch and a half of rubber!! The tyre is an old 3.50-19 Avon Speedmaster and although there is plenty of tread I think it needs to go, so any suggestions welcome

Roadriders every time

What he said. Best to change the front one at the same time.

I think that’s an Avon Speedmaster and I had the same problem with that design of tyre on my BSA in 1974! I reckon it’s only suitable with a sidecar fitted, where the bike doesn’t need to lean over.

Any other readily available, round profile tyre is probably better. You’ll get any number of different opinions, which proves the point.

I presently use a Dunlop K-70 lookalike (Cheng Shin) on my 350 and it’s perfectly good enough for the bike and quite predictable on corners. I previously used a Heidenau K67 knobbly trials tyre and that was also good, apart from very high wear rate.

Hideneau K34, 3.50x18 rear/3.25x19 front, perfect on a Bullet

Yeah, that's a sidecar tyre!
Avon Roadrunner (decent) or Pirelli City Demons (budget) for me.

You sure it's not a safety mileage? They stopped making speedmaster rears decades ago so if it is one, I'd get it changed. Standard on a bullet is a safety mileage rear and a groove-cut speedmaster mk2 on the front.

I ran them for tens of thousands of miles on my 350 bullet and I'd run out of ground clearance before running out of grip, could get the mainstand grinding on both sides. Genuinely never had a grip issue with them and they are excellent on unmetalled roads. People have a tendancy to over-inflate them, then you land up cornering on the "corners" of the tyre. If you inflate it to the book pressures, the tread doesn't come off the road, the sidewalls just flex so they actually have quite a large contact patch.

Roadriders are definately better, but equally, they don't last 10k miles. My main worry on a standard bullet is they'd land up squared off quite quickly due to the overall lack of both power and ground clearance.

Yes, you’re right, my error it’s actually an S-M. Which also stands for sadomasochism...

Will start looking on the interweb, many thanks, kally

I’ve got the S-M. Been running at 25F 30R. Looks about right for what Avon say. Riders manual shows 24/26 and 28/32!
I’ve slipped a couple of times, might give 24F/26R a shot.