Wheel is doing my head in.

[iAmiAdam]

When to get some new tyres on sunday, 26 inch 1 3/8 road tyres, went to fit them, and they didn't god knows how we got it on, but the people at halfords had to cut it off. this baffles me because the tyre that came off is a 26 x 1 1/4, so in theory I had an 8th of an inch to play with. Now I'm no mathmetician but this doesn't make sense to me. The bike is from the 70's so the only possible explanation is the tyre sizing has changed maybe?

Any ideas?

 

[brokenbetty]

Welcome to the wonderful world of tyre sizing!

http://www.sheldonbrown.com/tire-sizing.html

It makes more sense when you look at the ISO size - the big number is the diameter

26 1 1/4 = 597mm diameter
26 1 3/8 = 590mm diameter

(modern 26" mtb is 559mm)

so your new tyre was 7mm diameter too small for your rim. It's not surprising it didn't fit, though it's quite surprising you got it on in the first place!

 

[iAmiAdam]

Right, it makes sense now, that website didn't to me really.

Yh, We nearly buckled the rim doing it, but somehow we did.

 

[hubgearfreak]

god knows how we got it on

i'm impressed. you should go in for the old ripping up phone books party trick

 

[iAmiAdam]

Got the jersey for that already.

 

[iAmiAdam]

Need this answering once and for all.

My BSA Javelin, from 1970 something. 26 x 1 3/8 didn't fit. It says 26 X 1 1/4 on the tyre wall. 32-597

The sizing system hasn't changed since 1970 has it?

And will these tyres fit; http://cgi.ebay.co.uk/Kenda-26-x-1-...arts_SR&var=&hash=item61ca2fa01b#ht_600wt_732

 

[brokenbetty]

Yes those tyres will fit.