andrew_s
Legendary Member
- Location
- Gloucester
35mph = 56.3kph = 938 metres per min
at 221 rpm => 4.25 m per pedal rev
on 42x15 => 4.25 x 15 /42 m = 1.5m per wheel rev
so your wheel is 48cm in diameter - 20x1.5"?
If you are using 700c, something's gone wrong somewhere. 35mph on 42x15 should be more like 160rpm (25mm tyres)
at 221 rpm => 4.25 m per pedal rev
on 42x15 => 4.25 x 15 /42 m = 1.5m per wheel rev
so your wheel is 48cm in diameter - 20x1.5"?
If you are using 700c, something's gone wrong somewhere. 35mph on 42x15 should be more like 160rpm (25mm tyres)