Tyre size conversion help!!
 

Hey there, I'm looking to get my hands on some 27'' tyres for a pair of old Mavic e2 rims. Thing is, I'm not quite getting the sizing. The rims appear to have an inside diameter of 19mm so I thought I was looking to get 23mm tyres! However i was terribly confused to find 27'' tyres come in

27 x 1 1/4
27 x 1 1/8
27 x 1

Which of these do you think would be the equivalent of 23mm tyres?

Cheers, and thanks a mill in advance. I'm very sorry if this has been asked a hundred times before, it's quite tricky to use the search for specific numerical sizes!

You shouldn't have any problem with any of those sizes on your rims: It's more a matter of how heavy/cushioned you want the tires to be. I have slightly wider rims and I'm running 1 1/4 on them.

1.00 inch = 25.4 mm

1.125 inch = 28.575 mm

1.25 inch = 31.75 mm

Cheers guys. From the looks of things 27x1 are nigh on impossible to get in Ireland/Europe for a sensible price.
I'll look into 1 1/8

Good quality 27" tires are becoming increasingly difficult to find. The last time I went into a local shop for 27" tires, they had ONE 27 x 1 1/8 tire and a low selection of 1 1/4. I'm glad I no longer own any 27" wheels.

Some times it's easier to get tires if you use the etrto or ISO designation. You're looking for a 25-630 or 28-630.

I believe shwalbe used to make these, but you might have to buy them in the USA, or south America. Sometimes the way to deal with this kind of stuff is to have a friend buy it for you and pony it home in his luggage or as a carry on.

I keep 2 bikes in Mexico, and was so careful to make sure they had 700c tires. Little did I know that Mexico is the last bastion of 27x wheels and 700c tires are impossible to get there. That's when we resort to the Air-pony express.

Yeah, I'd never knowingly get involved with 27'' tyres however after a poorly listed ebay sale, nearly $100, and a lot of time restoring I find myself stuck in this position. I found that Continental Ultra Sport come in 27 x 1 1/8 so they may the easiest (if not the best quality) solution. Thanks for the info.