Bicycle tire sizing guide - sizes, dimensions and uses

- Introduction into tire sizing for bicycles

Bicycles tires have gone through a big leap over the last 15 years, there are new sizes available and also special tires for very special applications.

I believe the two most common sizes are 26 and 28 inches. The ISO ERD sizes would be for example 54-559 and 35-622 respectively. Here's what these numbers mean:

54 – tire width in mm (just an example size)

559 – ERD or effective rim diameter. This is the size of the tire that sits on the rim and is not the real diameter of the wheel.

The inch system is similar, but dimensions are given this way: 26x2.2 (26 inches ERD and 2.2 inches width).

 - Buying tires and planning ahead

When planning on getting new tires, there are several things to check – dimension, tread type and tread width. On some cheaper tyres, the width might be stated as 2.2 inches / 54mm, but the tread may be sticking out quite a bit more. This is especially important for city/trekking bicycles as they have narrow chainstays and the tire may start rubbing the frame (and this will eventually wear the paint off and might even damage the frame, regardless of being aluminium/steel).

 

 - Punture proof, puncture resistant - what does it mean?

In terms of protection, there are 3 types of tires available: no protection, puncture resistant and puncture proof. 99% of cheap tires (costing 12-14 usd / 8-10 eur) have no protection at all.

Puncture resistant tires are a bit more expensive (20 usd/16 eur), but unless you run over a spike strip used to stop cars, it should keep random punctures and flats away.

Last but not least are puncture proof tires. Their price ranges from 30usd to up to 60 usd (25 eur to 53 eur) with the more expensive ones have excellent manufacturer warranty aswell (Schwalbe Marathon Plus has 5000km and 3 year warranty on any prodction defects).

I have never seen a flat with Schwalbe Marathon Plus tires that could be classified as a puncture (I did see one tire that had been punctured on the sidewall by a metal rod. But the owner decided to repair the damage using kevlar thread and the tire is still in use today).