When changing bicycle tyre section, you need to make sure that the section your are opting for is compatible with the width of your rims. Failing to do so would put you at risk of getting your tyres off the rim in action, or of prematurely wearing out your tyres. If the tyre is too large relative to the bike’s rim, you are in serious risk of tyres getting off the rim without warning. The shape of the tyre once in place also won’t be as intended, and your will loose lateral grip. If the tyre is too narrow relative to the rim, you are going to roll as much on sidewalls as on the center tread and the tyre will wear out quickly.
The following table will enable you to identify the range of tyre sections compatible with your bicycle rim. Start by identifying the ETRTO of your rim.
The ETRTO code gives the following information:
• 2 digit number, which corresponds to the inside width of the rim: for example 19C. This data is in millimeters and that’s the criteria being used to identify the range of tyre sections compatible with a given rim.
• 3 digit number, which corresponds to the rim’s diameter in mm. For example a 27.5″ MTB wheel has a diameter of 584mm.
Your should find this ETRTO code on a sticker, or engraved on the rim. If not you will find it in the technical specifications of the rim. You can also measure it, using a caliper: it corresponds to the inside width of the rim at the level where the tyre beads sit.
For example, you own a twentyniner MTB bike and would like to mount narrow slick tyres like the Hutchinson top slick for winter road use, but you are not sure which section to go for between the 29 x 1.25 (32-622) and the 29 x 1.50 (37-622).
Let’s say the ETRTO code of your rim is 19-622 (which may also be shown as 622 x 19C). According the table below, you can mount tyres with sections ranging from 28mm to 62mm. Therefore both the 29 x 1.25 (32-622) and the 29 x 1.50 (37-622) are OK. The wider tyre will give you better comfort.
Of course you need to also make sure that the tyre section chosen is not only compatible with your rim but also with your frame and any mud guards, especially on city trekking tyres.The current trend is for rims to get wider, therefore when mounting thin slick tyres on an MTB, one need to be particularly careful of not taking too narrow tyres.
|Rim width (mm)||Tyre section (mm)|
No related posts.
Slider by webdesign