Cycling UK Forum

Hello Everyone.
I need to buy the best tyres i can for these rims.

This is what is printed. Photos attached.

26 x 1/2
020
type 112
steel
schurmann
Made in West Germany

From a GPO Postie bike form around 60s or 70s. It has rod brakes

If anyone can help suggest a brand and tyre spec I'd be very grateful

Trying to get a bike up and running I've had in the loft for a while after some ******** stole my 1950s Elswick Hopper Butcher's bike pride and joy. ahhhhh

thx... Ian

I think you've left off the 1". It's 26 x 1 1/2 , which I'm not familiar with. Sorry.

26 x 1-1/2" rims (a Dunlop size invented over 110 years ago ) have a 584mm bead seat diameter. This means that tyres labelled variously as 650B and (bleurgh) 27.5" will fit these rims. Which shows you what can happen if folk from other countries misappropriate your tyre sizes.

if that is your size (which is what the labelling on the rim is saying, and it is the correct size for GPO bikes from 1927 until Pashley prontos) any of the tyres on this page

https://www.sjscycles.co.uk/tyres-26-275-584-650b/

will at least fit your rims, even if many of them won't be the right width or to your taste exactly.

FWIW Michelin Zig-zags were the usual tyre used by the GPO all through the 1970s; Michelin world tour is the closest to this size now, although it might be slightly narrower at 35mm width.

cheers

The pedant in me wishes to point out that that is a westrick rim. Sorry

Brucey wrote:26 x 1-1/2" rims (a Dunlop size invented over 110 years ago ) have a 584mm bead seat diameter. This means that tyres labelled variously as 650B and (bleurgh) 27.5" will fit these rims. Which shows you what can happen if folk from other countries misappropriate your tyre sizes.

cheers

Ignoring the "British rims for British riders" rhetoric (aren't those Dunlop tyres good?), this is of course why we ISO markings.

Bmblbzzz wrote:Ignoring the "British rims for British riders" rhetoric....

maybe you partly missed my point. If there hadn't been a 'French rims for French riders' mindset (and BTW an 'everything must be in mm' mindset to go along with it ) there wouldn't ever have been a 650B 'standard'; all they did was copy the Dunlop dimensions, and then didn't even bother to maintain their new 'standard'. Same with 700C sizing too; it is again a renamed Dunlop size. Likewise if there hadn't been a (marketing driven) urge to call tyres (that fit the same 584mm rims) 27.5" tyres there again would have been less confusion.

I heartily approve of ISO tyre sizing (and I just wish that more tyre manufacturers actually used it). However all it does is build on the preceding Dunlop, ETRTO (and DIN, and BS etc) sizing standards, which are clearly marked on the OPs rims, and may have been forgotten about....?



cheers

Brucey wrote:

Bmblbzzz wrote:Ignoring the "British rims for British riders" rhetoric....

maybe you partly missed my point. If there hadn't been a 'French rims for French riders' mindset (and BTW an 'everything must be in mm' mindset to go along with it ) there wouldn't ever have been a 650B 'standard'; all they did was copy the Dunlop dimensions, and then didn't even bother to maintain their new 'standard'. Same with 700C sizing too; it is again a renamed Dunlop size. Likewise if there hadn't been a (marketing driven) urge to call tyres (that fit the same 584mm rims) 27.5" tyres there again would have been less confusion.

I heartily approve of ISO tyre sizing (and I just wish that more tyre manufacturers actually used it). However all it does is build on the preceding Dunlop, ETRTO (and DIN, and BS etc) sizing standards, which are clearly marked on the OPs rims, and may have been forgotten about....?



cheers

Love the cartoon

Just to qualify the comment about it being a Westrick rim rather than a Westwood.
It shouldn't affect tyre size, the difference is a Westrick will take braking on the inside of the rim (think Rod brakes)
And also on the side if the rim ("Convetional" side/centrepulls)
Westwood will only take the ' inside ' brake .

It's not "misappropriation" to adopt an existing size and relabel it in units a different market understands. It happens with all sorts of products. Nor to adapt the original in response to changing conditions, such as fitting different sized tyres for different riding uses.

Bmblbzzz wrote:It's not "misappropriation" to adopt an existing size and relabel it in units a different market understands..

"understands"? All tyre markings are in essence arbitrary. When an existing tyre size is simply given more than one different name, all it does ultimately is to breed confusion.

For example even though 650 is an allusion to the wheel diameter, '650B' is just another quasi-random designation (they may as well have called it 'trevor' or something).

Similar criticisms apply to using 27.5" as a designation. Very few 27.5" tyres actually measure 27.5" diameter and furthermore there are plenty of other tyres what are about 27.5" diameter that won't fit those rims. Again they would have been as well (or better) off if they had used a different name, like 'Tyre McTyre Face'; it would have been about as meaningful and about as useful.

I think that all tyres and rims ought to be marked with the ISO size. Probably for historic reasons they will end up with other marks on them as well, but those marks are always (at heart) largely arbitrary and the more different ones there are for the same thing, the more likely it is to cause confusion.

"Misappropriation"? Yeah, I'll stick with that.

cheers

9494arnold wrote:Just to qualify the comment about it being a Westrick rim rather than a Westwood.
It shouldn't affect tyre size, the difference is a Westrick will take braking on the inside of the rim (think Rod brakes)
And also on the side if the rim ("Convetional" side/centrepulls)
Westwood will only take the ' inside ' brake .

Quite correct. As I said it was me being a pedant.

Brucey wrote:For example even though 650 is an allusion to the wheel diameter, '650B' is just another quasi-random designation (they may as well have called it 'trevor' or something).

Similar criticisms apply to using 27.5" as a designation. Very few 27.5" tyres actually measure 27.5" diameter and furthermore there are plenty of other tyres what are about 27.5" diameter that won't fit those rims.

I'd think of 650B, 27.5" and -584 as two different philosophies. The ISO approach measures BSD, obviously, whereas the other markings measure (an approximation of) overall diameter. So in terms of, so to speak, engineering compatibility, ISO is the only reliable marking; but in terms of usage compatibility, 27.5 and 650B usefully indicate different applications. Great when you know you want a mountain bike tyre, say, but leading to potential confusion when you want a "road" tyre for an "off-road" bike, or anything that falls between marketing boxes.

I think that all tyres and rims ought to be marked with the ISO size.

I'm pretty sure they all are now.

As for "understanding", I mean that if a tyre size had been introduced from, say, France or Germany to Britain in the early 20th century, it would have been renamed with an Imperial-based designation to avoid customer bewilderment at these millimetre things. Doesn't just have to be tyres of course, can be pretty much any consumer goods.