SPD's power advantage....Myth?

supersonic

Extensor muscles are the quads, which push. It does seem that some do develop the flexor muscles effectively which raises efficiency for that rider. Figure 1 also shows that maxiumum torque was produced when actively pushing, but the study only went as low as 70rpm. Would have been good if it said which was the preferred technique of each rider, but I guess it is a combo of all the lot, rather tan focussing on one specific technique.

It was interesting that pulling evened out the torque curve, but also lessened eficiency.

Pardon the pun lol, but coming full cicrle I think it demonstrates that the best method at the moment you is the one you currently employ, but you could make it better. Or indeed worse. It is indeed down to the individual, preference, style, cadence and muscle development.

always_tyred

supersonic wrote:

Extensor muscles are the quads

Yup, I got that part. My point was that it was a bit of a "scientists discover that toast has 50% chance of falling butter side down" statement.

It was interesting that pulling evened out the torque curve, but also lessened eficiency.

Pardon the pun lol, but coming full cicrle I think it demonstrates that the best method at the moment you is the one you currently employ, but you could make it better. Or indeed worse. It is indeed down to the individual, preference, style, cadence and muscle development.

I agree. Terrible pun. Go and stand in the corner.

But yes, I think we are agreeing.

Okay. Lets tackle aero positions next!!

supersonic

I wear baggies and use riser bars.

And flat pedals;-)

always_tyred

supersonic wrote:

I wear baggies and use riser bars.

And flat pedals;-)

I think you could get more aero.

Ben6899

tjwood wrote:

I've never used SPDs, but with decent (grippy) flat pedals and appropriate shoes, once you've placed your foot on the pedal it stays there until you deliberately remove it. No slippage. You can certainly pull in either direction at 6/12 o'clock.

Given that, I can't see how there is any mechanical advantage to having your foot physically connected to the pedal. How is the physics any different in either case?

All the pro riders are wrong.

meanredspider

snailracer wrote:

Soft engine mounts, sprung clutch plates and rubber bushings ("donuts" as you call them) were all introduced on passenger cars to reduce vibration and has nothing to do with losses.

Aaaaah - I can't help myself but respond to this rubbish.

If they have nothing to do with losses, why are they removed on race cars and replaced with ultra-stiff versions? Because racing drivers (like me) love vibrations? Yeah, right! I assume you've driven a car where these are removed and understand, in doing so, what difference they actually make?

You only seem to half understand what you are talking about. For instance, a damper only provides damping reaction not force. Your description of the trainer deformation demonstrates you don't seem to understand that or you think that I've argued that there's no spring effect or something.

And my point about jumping off the wall was to make you think about how it would feel in one shoe rather than the other to get you to realise that the trainer absorbs (some) energy whereas the stiff-soled bike shoe would all-too-effectively transmit it to your legs. Nothing to do with the marketing blurb. Nothing to do with bikes. Just a simple idea to demostrate the difference between the two shoes that you don't seem to want to accept.

I don't really know why I'm bothering though...

night_porter

All of this discussion seems a little strange to me.

If you like clipless, use them.

If you don't like clipless, don't use them.

If you have never tried clipless but would like to, try them.

If you have never tried clipless and would not like to, don't try them.

Because we are all different some will like them and some won't.

Simples!!!

PS If supersonic can get more Aero can I get more Flakes

itsbruce

You're missing the point. Somebody has noticed that other people willingly cycle in a way different to him. They must be wrong-headed and this has to be made clear to them.

bearfraser

There must be someway (a load cell???????) to test this theory for once and all !!!

UndercoverElephant

This all started due to a article on the main page. Here's a different article from Bikerader...

http://www.bikeradar.com/fitness/articl ... ster-26895

The outcome was that pulling on the upstroke was the only method that showed any improvement in mechanical effectiveness.

snailracer

I can't believe how heated some people are getting about this, on the COMMUTING forum.

surreyxc

Thought I would add to an already over subscribed forum.

SPDs:
connect to pedal, stops foot sliding forward, do not need to continually adjust foot position, stiff soled shoes. When pedalling fast foot stays in place.

Flats.
Promotes good technique, learn to lift bike off ground correctly, allows foot dabbing round corners, and technical sections off road. Great when you have to push.[/list]

UndercoverElephant

snailracer wrote:

I can't believe how heated some people are getting about this, on the COMMUTING forum.

You obviously don't remember the Hi-viz wars of Autumn 2009. I've never seen such bloodshed. We lost some brave posters during that one.

mudcovered

snailracer wrote:

The clips that can accommodate straps are not the ones I am talking about.

I am referring to these:

I realised that. The point I was making was that without straps binding the shoe to the pedal you might as well not bother. Yes the toe clip gets your foot in the right place but at the cost of having to flick the pedal into the right place every time you put your foot down. If you are going to pay that cost you might as well have the straps to hold the shoe in place. Either that or just stick with flats and get rid of the inconvenient flip.

SPD gives you shoe placement accuracy. A nice attached to the pedal feeling and no need to flip the pedal the right way up (at least for the double sided sorts). If you don't think people who use SPD pull up on the pedal try watching someone who has used SPDs for 15 years try to ride a bike with flats. I guarantee you they will lift their foot of the rising pedal some of the time (I know I do).

Mike

Greg T

UndercoverElephant wrote:

You obviously don't remember the Hi-viz wars of Autumn 2009. I've never seen such bloodshed. We lost some brave posters during that one.

True.

Second only to the RLJ clan warfare and vendetta that has been blighting our happy community....

Also

snailracer wrote:

I can't believe how heated some people are getting about this, on the COMMUTING forum.

That's right princess - no-one's racing on here..... performance is only for the Road boards....

snailracer

mudcovered wrote:

snailracer wrote:

The clips that can accommodate straps are not the ones I am talking about.

I am referring to these:

I realised that. The point I was making was that without straps binding the shoe to the pedal you might as well not bother. Yes the toe clip gets your foot in the right place but at the cost of having to flick the pedal into the right place every time you put your foot down. If you are going to pay that cost you might as well have the straps to hold the shoe in place. Either that or just stick with flats and get rid of the inconvenient flip.

SPD gives you shoe placement accuracy. A nice attached to the pedal feeling and no need to flip the pedal the right way up (at least for the double sided sorts). If you don't think people who use SPD pull up on the pedal try watching someone who has used SPDs for 15 years try to ride a bike with flats. I guarantee you they will lift their foot of the rising pedal some of the time (I know I do).

Mike

I have that experience, too. But I wasn't sure my foot was actually lifting, it might have been sliding off to the side, front or back.

When I switched over to the toe cups, I found I wasn't any slower over any of my routes. Perhaps that is due to my steady high cadence, manic gear-changing riding style, which obviously not everyone subscribes to.

always_tyred

itsbruce wrote:

You're missing the point. Somebody has noticed that other people willingly cycle in a way different to him. They must be wrong-headed and this has to be made clear to them.

Aren't you rather missing the point of a forum? If you want some group where everyone is in complete agreement, a religious cult is what you are after.

As for the debate - its mildly diverting and not in the least heated. You know- intellectual engagement? Not big brother or the national lottery draw? Hello?

mudcovered

snailracer wrote:

I have that experience, too. But I wasn't sure my foot was actually lifting, it might have been sliding off to the side, front or back.

I can be fairly certain its a lifting motion. I only have about an 80% chance of my foot going back onto the pedal when riding without spds.

I've never really compared speed. I've been using SPDs for so long now I don't find it much of a hassle to change shoes before riding even for commuting. I just leave a pair at work.

Before I switched I was always finding that the pedals shredded the bottom of any shoes I wore very quickly so different shoes for cycling appealed anyway.

Mike

Specialized Needs

I almost feel like I should introduce myself, like the start of an AA meeting...

In the last year I have used toeclips, both strapped and strapless and, currently, SPDs. I do not know how much/if the SPDs help me uphill. However, there are a few comments about toeclips I would like to challenge.

mudcovered wrote:

Yes the toe clip gets your foot in the right place

Sort of, but to nowhere near the optimisation I found that I got from a recent bike fitting of my SPDs.

but at the cost of having to flick the pedal into the right place every time you put your foot down.

No biggie, this. With clips, the pedal hangs naturally "toe down". I became adept at scraping my shoe back across the edge of the pedal to flip the clip up, then nestle the toe forward. It doesn't take long to learn and it is a single movement. I find double sided SPDs as much if not slightly more hassle to clip in. Actually, my best experience has been SPDs with PD-22(?) flats on them, as (if the pedals are greased enough) the flat pedal naturally weighs down and presents the cleat fitting consistently.

If you are going to pay that cost you might as well have the straps to hold the shoe in place.

My two accidents/incidents have been due in part at least to my inability to get my foot out of a strapped toeclip. Commuting, I felt safer with strapless.

Either that or just stick with flats and get rid of the inconvenient flip.

As above: I didn' find this inconvenient

SPD gives you shoe placement accuracy.

Yep, and by far this is the greatest reason I use them, particularly the accuracy and consistency (clips are consistent positioners, but not necessarily accurate ones - pedals can be accurate (after you shift your foot around a bit) but not as consistent, I found). I believe this has improved my technique and so power, as has the training to pedal 'in smooth circles' rather than just 'up and down', whch I feel the cleats have helped me with.

A nice attached to the pedal feeling and no need to flip the pedal the right way up (at least for the double sided sorts).

If you don't think people who use SPD pull up on the pedal try watching someone who has used SPDs for 15 years try to ride a bike with flats.

I pull up. Sometimes that is all I do on either foot (is that wrong, by the way? Someone once told me it was not a good thing to do - I do it when my usual muscles are aching, as a rest, just to rest them and keep moving). However, I am not sure whether it helps with hills in the same way as the article challenges. I have found the aforementioned pedalling in circles rather than up and down is most effective for me for hills, and I find the cleats help this technique.

I guarantee you they will lift their foot of the rising pedal some of the time (I know I do).

Mike

cee

so...stiff soled shoe...less loss of power...i can go with that.
spd...allow a stiff soled shoe without them slipping...ok.

some of the other comments about definitely more power...perhaps thats a 'feel' thing...and if so...i can go with that...

as i say...been thinking about trying them for a while now...so maybe i just should and make my own mind up.

Ta,

C

always_tyred

There's another potential flaw with the studies that have been highlighted. The measurements appear to be pressure on the pedal. Pedals tilt. When I "pull up" I'm actually pulling intomy heel cup, with my toes down, essentially dragging my feet back using my hamstrings. At the bottom of the pedal stroke, I'm still pressing on the soles of my shoes, but again with toes pointed.

Both of these would be measured in that study as downward pressure, I think, whereas components of force backwards and upwards would be conferred by the foot angle.

Surely they thought of that? Anyone?

cee

Always Tyred wrote:

There's another potential flaw with the studies that have been highlighted. The measurements appear to be pressure on the pedal. Pedals tilt. When I "pull up" I'm actually pulling intomy heel cup, with my toes down, essentially dragging my feet back using my hamstrings. At the bottom of the pedal stroke, I'm still pressing on the soles of my shoes, but again with toes pointed.

Both of these would be measured in that study as downward pressure, I think, whereas components of force backwards and upwards would be conferred by the foot angle.

Surely they thought of that? Anyone?

I do this with flats also....the exageration of this is essentially how to bunnyhop properly...that toes down, scooping backand up motion...

no idea how any actual measurement was done though...

always_tyred

Small point - what's all this "bunny hopping properly" stuff?

That's like arguing that you need to learn how to change gear "properly" with downtube shifters. Or, indeed, how to pedal "properly" using a fixie and/or clipless pedals. :?

supersonic

I think when you bunny hop with flats you may be inclined to move your weight more effectively.

As for the angle of the pedal in the studies, one does show a force diagram and different parts of the stroke. Given that 'circling' was also studied, I would assume that force was measured in all directions, as was the pedal angle. But is an assumption.

Aidy

The Beginner wrote:

rjsterry wrote:

The Beginner wrote:

Even standing up the most force you can apply to the pedals is your body weight

Not sure I agree with this. Your leg miscles are more than capable of lifting your body weight and quite a lot more.

Newton, every action has an equal and opposite reaction, exert more force than your body weight and you raise your body until your leg is straight the only force then acting down is your body weight, so as I stated, the most force you can apply is your body weight. (leaving aside the very short time taken to raise your body, which is minimal since you exert force at the top of the pedal stroke anyway.

Simon

Coupled forces.

wgwarburton

Hi,
Six pages on SPDs?

What surprises me is that there's any room for a discussion on flats vs SPDs. We recently had a discussion on whether clipless systems offered any real benefit over toeclips for commuting., and I think strapless clips were mentioned there, too.

It seems obvious (though that doesn't necessarily mean it's correct) that having your toes firmly located in the right place on the pedal is a Good Thing. It appears this can be achieved by-

1) Good flats with the right shoes
2) Strapless toeclips
3) Toeclips
4) Clipless pedal systems.

I'm personally not convinced by #1, but can't speak from experience, so for the purposes of this argument let's assume it can work as described.

I think that it's understood that there's no power advantage to being able to "pull up" over the long term- your body can't supply that many big muscles with enough fuel & air to sustain them.
There may well be a a short-term torque benefit to being able to pull up.. OTOH it may be more effective to rely on pulling up on the bars while you push down to increase your torque. I daresay you could devise an experiment to prove this but the outcome would presumably depend on the rider, riding position, gearing....

So... I suggest that it comes down to practicality- flats can be a pain 'cos your feet tend to slide about. Strapless clips help, but are rare and not as effective as proper clips/or clipless. Toeclips work well enough but you need to learn how to use them, whereas clipless systems are easy to use and there's a pretty decent range of appropriate shoes (plus they make you look like a serious cyclist).

The "power advantage" isn't really the issue- it's finding a practical, easy solution to effective pedalling that matters... and for most (but by no means all) people, clipless systems are the easiest answer.

Cheers,
W.

Aidy

cee wrote:

from the climbing technique article on the front page......

according to cycling coach Dr Auriel Forrester of Scientific Coaching: “Pulling up on the pedals decreases power output as it interferes with the all-important downstroke on the other side – specifically, you can’t pull up against gravity at the same rate or same force as you can push down with gravity!”

why do commuters go to the bother of wearing spd shoes? Surely knowing that there is no power advantage (in fact a disadvantage is suggested...) why not wear shoes that are easier to walk in....

I kinda reckon this is poor phrasing, pulling up will increase power output - but at the cost of a loss of efficiency. i.e. it's better to spin faster and put less power through a pedal revolution.

Anyone who's actually tried to use SPDs will attest to the fact that you can accelerate much faster on them - because you can increase your power output by pulling up. This isn't really going to be a good way of riding for a sustained period of time, though.

cee

Always Tyred wrote:

Small point - what's all this "bunny hopping properly" stuff?

That's like arguing that you need to learn how to change gear "properly" with downtube shifters. Or, indeed, how to pedal "properly" using a fixie and/or clipless pedals. :?

was more of an example of when the same spd technique you describe is used by flat pedal users....and if thats what the 'pulling-up' technique is....then its moot.

SS does have a nice point about weight shifting though...

I think that being able to bunnyhop properly is an advantage over relying on being connected to lift the wheel.

<faux-naive-but-giving-the-benefit-of-the-doubt-mode>
And why wouldn't you want to change gear properly using downtube shifters? presumably you would want to get into bad gear combinations for chain line issues etc....
</faux-naive-but-giving-the-benefit-of-the-doubt-mode>

Gussio

SPD = Silly Pedal Dispute?

itsbruce

Always Tyred wrote:

itsbruce wrote:

You're missing the point. Somebody has noticed that other people willingly cycle in a way different to him. They must be wrong-headed and this has to be made clear to them.

Aren't you rather missing the point of a forum? If you want some group where everyone is in complete agreement, a religious cult is what you are after.

As for the debate - its mildly diverting and not in the least heated. You know- intellectual engagement? Not big brother or the national lottery draw? Hello?

Do I have to put the smileys in to stop your default asshole mode?