Tyre Sizes - Grrr!!

[grhm]

I've had a few puncture problems with the wife's trike - an old Pashley Picador. It's got unusal size wheels - they're 20" but fairly narrow. I've failed to get replacement inner tubes from my LBS or Halfords - they do 20" tubes but only in wide BMX sizes.

I've tried one or two wide tubes but have ended up trapping the tube and got a flat. The front tyre is also out of round. The rim seems round but the tyre isn't and it's noticable as I pootle along on it.

So I thought I'd buy a new tyre and tube on the internet. The old tyres got a load of numbers and letters on it. It says "(500 x 35A) 20 x 1-3/8" so I bought a 20 x 1 3/8 tyre and it doesn't fit!

I've just measured the rims and according to Sheldon's site for rim sizing, I've got 500A rims - over a centimeter smaller than 20x1-3/8 rims. Looking back at the tire in does say 500 x 35A - but I didn't know that means 500A and it is says 20x1-3/8, I thought 20x1-3/8 would fit.

Grrrr........

I'd just glad I only bought one tyre and didn't get all three in one go.

 

[Gerry Attrick]

Check out Schwalbe. I think they make that size.

 

[grhm]

Thanks for the tip - I've not had problems finding tyres on the web - I bought some cheap Michelin's from CRC - they come several in several sizes including both 20-1x3/8 and 500A.

Just having problems working out what size I need. Plus I needed to vent.