Bicycle Mechanics - 27x1-1/4" vs. 700x28-32

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View Full Version : 27x1-1/4" vs. 700x28-32


mooshrimp
08-10-10, 08:26 PM
I need to replace the tires on my bike, but I'm unsure what size to get. My rims say 27x1-1/4", but when I buy tubes for the tires both 27x1-1/4 and 700x28-32 are the same size tube. Sheldon Brown says they're not the same size, but the guy at the bike store said they were. Will a 700x28-32 fit my rims?


wrk101
08-10-10, 08:40 PM
No. It doesn't matter on tubes, they are basically a balloon you stick inside a tire, and they are the same size.

It matters on tires, A LOT.

Just go buy some 27 1/4 tires, and you are set.

BCRider
08-10-10, 08:44 PM
That's right, the tubes expand to fill a range of spaces. That's why they are listed as being good for both sizes. But the tires have belting and wire in them that locks their size. And of course the rims are whatever size they are. If it says 27 then you need 27's and not 700c.


mooshrimp
08-10-10, 09:09 PM
OK thanks. I thought so but was hoping not since it's hard to find that size. I should never question Sheldon again.

John Montgomery
08-10-10, 09:17 PM
Not so hard to find, I ordered mine through Amazon.com - under $10 a tire, came in a week...


(http://http//www.amazon.com/s/ref=nb_sb_ss_i_6_12?url=search-alias%3Daps&field-keywords=bicycle+tires+27+x+1+1+4&sprefix=bicycle+tire&ih=11_0_0_0_0_0_0_0_0_2.158_447&fsc=-1)

operator
08-10-10, 09:25 PM
The tyres are not interchangeable, the tubes are.

jimmuller
08-10-10, 09:54 PM
The tyres are not interchangeable, the tubes are.
Not to be pedantic but there is a minor point which might help the OP. Tubes really are different but not by much. It matters more for convenience than applicability. For example, a tube "rated" for a 25mm (1in) tire will fit into a skinny tire more easily than a tube listed for 32mm (1-1/4in). This makes it marginally easier to mount into a skinny tire without pinching the tube. Once the tire is seated however it matters not at all. Well, maybe one is a tiny bit lighter.