Bicycle Mechanics - bike spedometer

i have just purchased a sigma sport bc500 and have installed it
but in th manual it does not have my wheel size (24x2.10) is there a way of manually calculating it?

thanks

What exactly do you want to calculate? The rolling distance of the wheel/tire? Circumference?

in the manual it calls it WS Mph

any help

i have just purchased a sigma sport bc500 and have installed it
but in th manual it does not have my wheel size (24x2.10) is there a way of manually calculating it?

thanks

Yup, and it's easy too. Stand up your bike with the valve stem at the very bottom. Mark the floor in that spot. Now, weight your bike as if you were riding it and roll it forward exactly 1 revolution. Mark the floor again. Measure between the two marks in millimeters. That's your value. Normally this method will be a bit more precise than using the tire size values from the manual.

is that for km/h or mph

OK Private, I looked into this a little. If I have this right, the distance between your two marks in millimeters is the number you should enter for miles per hour.

24 x 2.10 is an odd sized tire. I'm curious what kind of bike you have.

Also, is there an ERTRO size on your tire? If so, it is probably on the label where you found the tire 24 x 2.10 tire size. It will be expressed as a two digit number followed by a dash and a three digit number.

If there is an ERTRO number, you might find the same number in the manual that came with your bike computer. Use it to calibrate your computer. ERTRO numbers are generally more accurate anyway.