Crank length out of saddle (again but maybe different?)

djbsmith59

Realise crank length has been done to death. But there are a couple of things relating to climbing out of the saddle that I haven't seen mentioned.

First off (I think) I get the basics. With a longer crank you have more leverage, but you need to move the pedal further and hence at same cadence faster, than a shorter crank. This balances out and you typically use a garder gear a lower cadence with longer cranks.

So, things I'm interested in the following in relation to climbing out of saddle -

- Biomechanics. Out of the saddle movement is fairly close to running. Longer crank length is analogous to a longer stride. Presumably there's an optimal "stride length" biomechanically speaking. Or perhaps different optimals depending what you want to achieve. Or is it mostly just you get good at what you're used to and no real advantage with in reasonable limits?

(I guess biomechanics applies to seated as well, but interested in climbing out saddle here)

- More benefit from mass accelerating? Out of saddle part of your power comes from your weight pushing down (rather than your muscle). If you drop something it accelerates. If you do one drop of one meter, the object's average speed will be greater than two drops of half a meter. Could this have a small effect benefitting longer cranks? Or is it counter acted by a longer dead spot with longer cranks?

fenix

You're overthinking this.
How much cycling do you do out of the saddle ?

It's not efficient to ride like that - you'd be better off with lower gears and staying in the saddle.

imposter2.0

You are right, this has been done to death. Within the normal range of available crank lengths, there is no performance benefit or viable biomechanical advantage to be had.

djbsmith59

I've seen studies showing that for sitting pedaling but not climbing out of saddle.

imposter2.0

Probably because you spend the majority of your time in the saddle, not out of it.

djbsmith59

Yeah, I realise that. I still find it interesting for it's own sake*, and it could be of practical relevance for hill climb tts or even climbers who are out of the saddle a fair bit - eg pantani apparently ran 180s in the mountains.

*Looks like I'm alone in that

imposter2.0

Even if Pantani did ride 180s in mountain stages (for which the actual evidence seems inconclusive), then you need to offset that against all of the other top climbers who didn't - and all of the current climbers who don't. It's not a reason to rush out and buy 180 cranks and it's not proof that longer cranks are universally more effective when climbing out of the saddle.

This is worth a read if you haven't already seen it:

http://myworldfromabicycle.blogspot.com/2010/08/dude-your-crank-lengths-fine-you-just.html

fenix

Pantanis climbing efficiency was helped no end by doping. It was that rather than the crank length that made the difference.

imposter2.0

fenix said:

Pantanis climbing efficiency was helped no end by doping. It was that rather than the crank length that made the difference.

Quite possible that the 'crank length' thing was nothing more than a diversion, much like Armstrong's mythical 'high cadence'...

djbsmith59

fenix said:

You're overthinking this.
How much cycling do you do out of the saddle ?

It's not efficient to ride like that - you'd be better off with lower gears and staying in the saddle.

I'm just interested in it for it's own sake. I'm not planning on getting longer cranks or anything.

I guess my interest does stem from my out of saddle power being much higher though. And I do ride out of the saddle a lot if going hard (for me) on climbs.

Less than eight minutes I'll be out of the saddle the whole way or maybe sit for twenty seconds or so if the gradient eases. Climbs of up to twenty minutes I'm probably about 50:50.

Longer than that and I'd be seated more but still stand a fair bit.

imposter2.0

djbsmith59 said:

I guess my interest does stem from my out of saddle power being much higher though.

Pedal force and power are not the same thing though, if that's what you meant. On a climb, power has to be sustainable and aerobic for it to be of any real use.

fenix

Your out of saddle power is helped with having your weight coming down on the pedals too ?
Sure you're putting more power down but it's using more energy to do it. Or you'd be able to keep it up for more than 8 mins ?

djbsmith59

imposter2.0 said:

djbsmith59 said:

I guess my interest does stem from my out of saddle power being much higher though.

Pedal force and power are not the same thing though, if that's what you meant. On a climb, power has to be sustainable and aerobic for it to be of any real use.

I mean power rather than pedal force.

And I guess it depends what you're trying to do really? Going for a strava segment or trying not to get dropped up a short hill then, for me at least, standing is useful.

Even on longer climbs I spend a lot of time of the saddle.

djbsmith59

fenix said:

Your out of saddle power is helped with having your weight coming down on the pedals too ?
Sure you're putting more power down but it's using more energy to do it. Or you'd be able to keep it up for more than 8 mins ?

But if I tried to do the same power for eight minutes sitting down, I just couldn't.

I agree that for the same power standing takes more energy though. Just for me at least, I can't get close to the same power sitting so it doesn't really matter too much which is more efficient.

davidof

I think the OP needs L shaped cranks for climbing.

me-109

On the stroke is it cranks before pedal or pedal before cranks? Maybe he needs Osymmetric rings to replicate the same effect?

StillGoing

djbsmith59 said:

fenix said:

Your out of saddle power is helped with having your weight coming down on the pedals too ?
Sure you're putting more power down but it's using more energy to do it. Or you'd be able to keep it up for more than 8 mins ?

But if I tried to do the same power for eight minutes sitting down, I just couldn't.

I agree that for the same power standing takes more energy though. Just for me at least, I can't get close to the same power sitting so it doesn't really matter too much which is more efficient.

That simply doesn't make sense. On a long climb, you'd pace yourself and be sitting putting out a lesser amount of watts. it's always fun riding with mates who go hell for leather trying to get a climb out of the way as quickly as possible, standing on the pedals, huffing, farting and panting. While myself and others sit there putting out enough power to get to top still in good shape and pass the other riders before the crest is reached, taking another gear and hoofing away.