Box Hill would kill me

[Dombo]

I have a Shimano Flightdeck that calculates virtual cadence from the gear indicator and roadspeed. Unfortunateley it is a POS and the left hand sensor is stuck on 30 chain ring (I have a triple as I'm old and live in hilly Surrey). I therefore get some pretty impressive cadence numbers on the downhills.

[Grahame]

I'd suggest that the max cadence registered is a false reading, probably causes by rotating the crank abckwards and forwards past the sensor whilst freewheeling downhill?

[Dombo]

Oh, is it not like Surrey? Or the Swiss Alps?

[Phil H]

I have hit that sort of cadence downhill on the fixie commuter (that's about 36mph on a 42x15). Can't say it was a lot of fun though.

[Phil H]

As an experiment I put my bike on the turbo (Garmin has magent on the back wheel so can get speed and cadence) and tested to see what I could pedal to. On 50/11 that was 55.7mph at about 158rpm. And a new back tyre. Wouldn't fancy trying that on the road though.

[url=http://www.sheldonbrown.com/gears/]Sheldon's gear calculator[/url] will give you "mph at 100rpm" and stuff. Always useful - if you can't be bothered to set it up yourself in Excel.

[Dombo]

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[Dombo]

[quote="Sean Hogan"]Lol...er. Box Hill would be Cat Hors mon ami.

[Elliot M]

[quote="Dombo"]Geek alert:

Distance travelled by a 700c x23 wheel in one rev = diameter x pi = approx 720 x 3.142 = 2.26 metres per rev
Max speed = 32 mph (51kph)
= 51/60 kpm = 0.85 ie 850 metres per minute......: