 You don't need to be an 'investor' to invest in Singletrack: 6 days left: 95% of target - Find out more
as per my title... the cateye instructions have 2.125" and 2.3"... i guessed a setting roughly between the two.
cheers
Measure it?
Measure it +1
i will do that tomorrow, but just on the off chance that someone knew, it would save me digging out a tape measure from the deep, dark recesses of my diy tool kit
Depends how much pressure is in your tyres! If you want to get the most accurate measurment, chalk up a spot on your tyre and then ride the bike forward a few turns at your normal tyre pressures and riding weight. Measure the distance between the chalk dots on the road or kitchen floor if its big enough. The deflection of the tyre changes the radius of the wheel significantly enough to make quite an impact to the circumfrence measurment.
Yeah, the only accurate way to figure that out is by riding a known distance at normal tyre pressure and counting the wheel rotations. As grimy has pointed out, the measured circumference will vary with pressure and rider weight.