Question about Tyres :)

[stoi]

Hi everyone, just a quick question from a newbie (I've only started cycling over the past few weeks) about tyres if I may.

I have been in contact with an online cycling company regarding the purchase of some special tyres and they have asked me for to take a measurement of the "internal rim" of my current tyres/wheels.

Well, I'm afraid I am not at all sure what this means and any help on completing this would be most gratefully received :-)

Thanks very much.

 

[TissoT]

What make are the wheels/rims ....
Road ... mtb ...?

 

[Smurfy]

Sheldon has all the guff you need!

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

Normally people don't measure their rim, they just note down the sizes printed/embossed on the sidewall of their existing tyres.

 

[stoi]

Hi guys, thanks for your responses.

It's a mountain bike and has the markings on the of the side of the tyre as '50-559/26x1.9' but they are asking for the rim measurement in addition to this and I was unsure as to what this meant. Cheers.

 

[Boon 51]

Plus look for an arrow on the side wall of the tyre as some tyres have to be fitted one way only..

 

[Rickshaw Phil]

Hi guys, thanks for your responses.

It's a mountain bike and has the markings on the of the side of the tyre as '50-559/26x1.9' but they are asking for the rim measurement in addition to this and I was unsure as to what this meant. Cheers.

The 50-559 marking is the one that you'll need. 50 means the tyre is 50mm wide and 559 is the rim diameter (in mm) that you are being asked for, which is the standard size for 26 inch mountain bikes.

The other (26x1.9") markings are the imperial equivalents but they can be quite misleading as there are alternative sizes that are also called 26 inch and aren't compatible

It's important to get the right diameter tyres for your rims but you have more flexibility with the width which the link YellowTim posted will explain.