Tire Dimensions
Why are tires often narrower than the stated tire size?
In order to ensure that tires have sufficient frame clearance, tire manufacturers generally prefer to keep production closer to the lower end of the permitted tolerance (+/- 3 mm). Carcass casing materials have become more and more sophisticated over time. That reduces the tire widening after the fitting.
Furthermore, inflation pressure also plays a major role. With maximum inflation pressure the tire becomes wider than with low pressure. And a recently fitted tire still widens over time. This can make a difference of 1 to 2 mm. The tire width is measured at the widest point, i.e. outside the lug.
A tires mounted width is directly affected by the internal rim width of the wheel it is mounted on.
A larger internal rim width will yield a flatter cross-sectional tire profile.
Conversely, a smaller internal rim width results in a tire that is taller, but less wide.
When upgrading a tire, one should consider the internal rim width of their wheel as this will dictate if the new tire will be smaller, or larger then the width listed on the sidewall.
Will the tire fit into my frame?
The question whether tires will fit into a particular frame is often asked in relation to our ultra-wide tires.
Please bear in mind that with the large number of different bicycle models it is impossible to check the compatibility of all frames and tires. The following list shows the exact diameters and widths of our ultra wide tires. This should allow you to identify if there is sufficient frame clearance for the selected tire.
WHICH TIRE FITS WHICH RIM?
The inner diameter of the tire must match the rim bead seat diameter. For instance, a tire size 37-622 fits on a 622 x 19C rim.
Furthermore, the tire width must match the inner rim width. The following table shows possible combinations of tire widths and inner rim widths according to ETRTO, complete with additional Schwalbe recommendations.
Possible combinations of tire width and inner rim width
Hookless or straight-sided rims may only be combined with TLE/TLR tires (Tubeless Easy/Tubeless Ready).
The compatible types (tubeless) and tire widths specified by the wheel/rim manufacturer must be taken into account. In particular, the minimum tire widths.
This restriction applies regardless of the intended use (MTB, gravel/cross, city/tour, road bike).
Note: Always observe the information on maximum air pressure and tire type (tubeless/tube type) provided by the rim manufacturer.
WHAT IS THE EXACT CIRCUMFERENCE OF MY TIRE?
In order to accurately program a bicycle computer , it is generally necessary to enter the exact tire circumference.The tire circumference varies depending on the rim, the inflation pressure and the load on the tire. For these reasons, it is not possible to list an exact tire circumference. In order to accurately program a bicycle computer, we recommend a simple rolling test with the rider on the bicycle.
