## Tyres size 26 x 1 3/8 ?

utopia
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Location: Melbourne

### Tyres size 26 x 1 3/8 ?

Im thinking of buying some tyres with the size 26x 1 3/8", but arent sure what the equivalent is in modern terms ie 26x1.95 26x1.75 etc. Does anyone know?

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### Re: Tyres size 26 x 1 3/8 ?

utopia wrote:Im thinking of buying some tyres with the size 26x 1 3/8", but arent sure what the equivalent is in modern terms ie 26x1.95 26x1.75 etc. Does anyone know?

Generally 1 3/8 is almost the same as 35mm, so a 26 X 35mm will suit. But look at the ETRTO measurement that is generally also marked on modern tyres. 26" MTB tyres are 559, and you'll want 35-559. However there are at least 3 other 26" tyre sizes:

http://www.sheldonbrown.com/tyre-sizing.html
Some are old US sized tyres (less likely to see here), others are for time-trial bikes, or the 650B French touring size. Check your tyre sidewall, if in doubt get the bike shop to double check, especially if this is an old bike or from overseas.
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MichaelB
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### Re: Tyres size 26 x 1 3/8 ?

utopia wrote:Im thinking of buying some tyres with the size 26x 1 3/8", but arent sure what the equivalent is in modern terms ie 26x1.95 26x1.75 etc. Does anyone know?

well, 1/8" = 0.125", therefore, 3/8" must then be, um, err, 0.375". Stick a one in front of it and it becomes 1.375".

Then, by multiplying by the equivalence factor (and the general rule that 1" = 25.4mm) will give you 34.925mm.

So the tyre size you are after is a 35mm, as politely pointed out above, and not so by me.

What happened to maths at school ..

531db
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### Re: Tyres size 26 x 1 3/8 ?

MichaelB wrote:
utopia wrote:Im thinking of buying some tyres with the size 26x 1 3/8", but arent sure what the equivalent is in modern terms ie 26x1.95 26x1.75 etc. Does anyone know?

well, 1/8" = 0.125", therefore, 3/8" must then be, um, err, 0.375". Stick a one in front of it and it becomes 1.375".

Then, by multiplying by the equivalence factor (and the general rule that 1" = 25.4mm) will give you 34.925mm.

So the tyre size you are after is a 35mm, as politely pointed out above, and not so by me.

What happened to maths at school ..

Sorry, MichaelB you are way off the mark and your advice is wrong.

A tyre marked 26 x 1 3/8 will have a bead seat diameter of 590mm if it is of British or Australian origin. The same tyre marking was also used by Schwinn in the US on US made tyres with a 597mm bead seat diameter.

A tyre marked 26 x 1.375 in an Australian bike shop will be a 'mountain bike' tyre and have a 559mm bead seat diameter.

Ther are as Il Padrone said, even more so called 26" bead seat diameters (571, 584mm).

What utopia needs (and it is the only tyre that will fit his 590mm bead seat diameter) is a 26 x 1 3/8 (ETRO 35-590). Do not buy a 26 x 1.375 (35-559) because it will not come close to fitting on the rim.

531db

531db
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Utopia, Abbotsford Cycles (at Richmond Rail Station) have the tyres that you want.

See : http://abbotsfordcycles.com.au/public/c ... ew/97/113/

Schwalbe Marathon 26 x 1 3/8.

531db

MichaelB
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Location: Adelaide, South Australia
Point taken Mr dB.

But, my tongue-in-cheek was aimed at the width conversion.

Alas, this is a typical "standards" scenario, where what is written, can be interpreted several different ways. Talk about confusing.

kukamunga
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531db wrote:Utopia, Abbotsford Cycles (at Richmond Rail Station) have the tyres that you want.

See : http://abbotsfordcycles.com.au/public/c ... ew/97/113/

Schwalbe Marathon 26 x 1 3/8.

531db

They also usually have a cheaper brand in stock. I'm actually dropping in there later this morning. I'll ask....

Kid_Carbine
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531DB is right on the money, but to extend his advice there are three things to remember when it comes to English tyre sizes.
1. Don't try to convert to metric.
2. Never try to convert to metric.
3. Never EVER try to convert to metric.

The metriheads in the tyre industry never got it right & went off on their own little way with other sizes.
Carbine & SJH cycles, & Quicksilver BMX
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Aushiker
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Good advice can be found on Sheldon Brown's (RIP) website.

Andrew
Andrew

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Kid_Carbine wrote:531DB is right on the money, but to extend his advice there are three things to remember when it comes to English tyre sizes.
1. Don't try to convert to metric.
2. Never try to convert to metric.
3. Never EVER try to convert to metric.

The metriheads in the tyre industry never got it right & went off on their own little way with other sizes.

Ahh, well, the ETRTO sizing is metric, and I believe generally fairly reliable.

Bugger the idea of buying this 26" tyre that is different to this other 26" tyre, and just a bit bigger than this next 26" tyre

My 26" tyres are 559mm bead seat. I know that and can get other 559mm tyres to fit on my rims
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Kid_Carbine
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I was in error with my earlier post & it should have read, 'never convert English fractional sizes to DECIMAL sizes' & I apologise for the misleading statement.
I had unwisely linked decimalisation of Imperial inches directly to the Metric system. I will shortly 'necklace' myself [A South African term] with a half dozen old 20x1-3/8 tyres as punishment.

Actually, the ETRTO sizing specs are the only reliable method of ensuring that one size or another will fit your rim, but there are no decimal or metric equivalents to the English fractional sizes
Carbine & SJH cycles, & Quicksilver BMX
Now that's AUSTRALIAN to the core.