On 31 Mar, 15:31, David Damerell <[email hidden]>
Quoted message said:Quoting Pete Biggs <[email hidden]>:
Quoted message said:David Damerell said:Power, yes, but force? Until you get to pulling up on the bars (which
admittedly they do), the force one puts through the chain is just a
matter of chainring size and available lard.
In a sprint, they pull up on the bars to an extreme degree,
Extreme compared to ordinary cyclists? Yes. But as a proportion of their
body weight? Even the strongest sprinters have tiny arm muscles compared
to their leg muscles.
That's irrelevant on two grounds - you don't need huge arm muscles to
suppport more than your body weight for the few 10s of seconds of a
sprint. You do need hugh leg muscles to power you through a 200km TdF
stage. Also, if your elbows are straight, you need virtually no
muscles to transmit the force from your back to the bars.
And as I commented to Ben elsewhere in this thread, sprinters will be
very firmly clipped in, and will put a rather large upwards force on
one pedal as well as the downwards force on the other.
Quoted message said:I'd rather have said "if you can't break chains on a tandem, you can't
break them solo". I'll bet _two_ lardy blokes exert more force than one
pro sprinter, pulling up or no.
but you're unlikely to get two lardy tandemmers honking out of the
saddle, each putting their full weight on one pedal in a low gear,
which isprobably what you'd need to get the same sort of force a
sprinter will put in while accelerating in a sprint finish.
I can't say which is likely to be the larger force - they may be
similar in magnitude. The tandemmers have weight and low gearing, but
won't use their full weight on the pedals. The sprinter will put more
than his/her body weight onto a pedal, but will be in a much higher
gear.
TL