The merits of SPD SL's over SPD's

Simon E wrote:

...the bottom of the stroke, where it should feel like 'scraping sh*t off your shoe'.

Thank you for mentioning that. I also get o lot of power out of that motion which can only be fully exerted when using road pedals. There's also the other opposite of the pedal stroke to use.

In the end, the proper pedal technique advises us to use 100% of the motion. Now that does't mean we should pedal like that 100% of the time. Here's a video that goes into the details of this much debated subject.

bigmel wrote:

How your foot feels is what matters - stiff soles don't bend so you don't have an irritating rubbing/flexing/hot-spot or similar.

Hot spots are exactly what I experienced when I tried SPDs, despite the stiff soles of my shoes. The soles may not bend but I'm sure that pressure applied over a smaller area would have this kind of effect. Switched to Look Keos and the discomfort went away instantly.

bigmel wrote:

For the real world, use SPD shoes & pedals.
There is no "better power transfer due to the bigger platform they offer" - power comes from pressing down hard with your muscles!
How your foot feels is what matters - stiff soles don't bend so you don't have an irritating rubbing/flexing/hot-spot or similar. There are plenty of stiff SPD shoes out there but I have never had a problem with regular Shimano nylon-based soles.
(speaking as a regular club rider for the last umpteen years).

Spot on bigmel. I'd like to see some of these faux physicists perform in blind tests and then see if they get more power down in SPD SLs.
Normal humans, going about their normal business should be perfectly happy in SPDs and at a fraction of the costs too.

bigmel wrote:

For the real world, use SPD shoes & pedals.
There is no "better power transfer due to the bigger platform they offer" - power comes from pressing down hard with your muscles!
How your foot feels is what matters - stiff soles don't bend so you don't have an irritating rubbing/flexing/hot-spot or similar. There are plenty of stiff SPD shoes out there but I have never had a problem with regular Shimano nylon-based soles.
(speaking as a regular club rider for the last umpteen years).

Pressing down on the pedals is only about 40% of the pedal stroke. Pulling up your feet is an advantage that's too hard to ignore, specially when standing up. SPDs make it hard to do it due to massive amount of float they provide when compared to proper road pedals.

As for shoes with nylon-based versus carbon soles, I've had problems with foot arc pain with the former that were only solved by using my Bont Vaypors. That wouldn't have been a problem if I pedalled only pressing down with my muscles.

It's a matter of preference and riding style. On one end we have your experience, and on the other we have mine, both valid. Now it's up to the OP to make a decision based on his personal preference.

FullGas wrote:

Pressing down on the pedals is only about 40% of the pedal stroke. Pulling up your feet is an advantage that's too hard to ignore, specially when standing up. SPDs make it hard to do it due to massive amount of float they provide when compared to proper road pedals.

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I'm not convinced by this argument, in my uni years my friend came off his mtb and took a gash out of shin, and we swapped bikes and he pedalled the 6 miles to the hospital on one leg wearing my spds. pulling up is not that comfortable anyway as the leg muscles are not really evolved to work that way.

road shoes/pedals are lighter more aero and look better, mtb spds have the advantage of being double sided and fitting shoes you can walk in at the café.

wycombewheeler wrote:

FullGas wrote:

Pressing down on the pedals is only about 40% of the pedal stroke. Pulling up your feet is an advantage that's too hard to ignore, specially when standing up. SPDs make it hard to do it due to massive amount of float they provide when compared to proper road pedals.
.

I'm not convinced by this argument, in my uni years my friend came off his mtb and took a gash out of shin, and we swapped bikes and he pedalled the 6 miles to the hospital on one leg wearing my spds. pulling up is not that comfortable anyway as the leg muscles are not really evolved to work that way.

We also need to take into account the various SPD cleat options here. I find I can pull up easily in single release mode cleats, but regrettably they're getting harder to find (don't send me links, its not impossible) as most stockists prefer multi release mode cleats, which I always find disengage too easily.

FullGas wrote:

Pressing down on the pedals is only about 40% of the pedal stroke. .

Really? Are you talking about what percentage of the rotation each single leg makes? I would have thought the percentage of power produced would be much more relevant.

Just look at your legs. Your 'pushing' muscles are a lot bigger than your 'pulling' muscles. My understanding is that, at best, pulling up is just unweighting the pedal to allow easier pushing down on the other pedal. As I mentioned in my earlier post, GCN actually tried to put some science to this at Loughborough Uni, and the tests basically showed no difference between clipless and flat pedals (with Si pedalling in his road shoes on the flat pedals!). In fat, IIRC the results actually had the flatties slightly more efficient, but all well within margin of error.

Chris James wrote:

FullGas wrote:

Pressing down on the pedals is only about 40% of the pedal stroke. .

Really? Are you talking about what percentage of the rotation each single leg makes? I would have thought the percentage of power produced would be much more relevant.

Just look at your legs. Your 'pushing' muscles are a lot bigger than your 'pulling' muscles. My understanding is that, at best, pulling up is just unweighting the pedal to allow easier pushing down on the other pedal. As I mentioned in my earlier post, GCN actually tried to put some science to this at Loughborough Uni, and the tests basically showed no difference between clipless and flat pedals (with Si pedalling in his road shoes on the flat pedals!). In fat, IIRC the results actually had the flatties slightly more efficient, but all well within margin of error.

Obviously I'm talking about rotation. If you look at your cranks like a clock the pushing down part of the stroke goes from 1 to 5 o'clock, therefore 40%. Another benefit you can get from a smooth pedal stroke is better balance and bike handling.

I love the GCN guys as much as the next guy. But, I wouldn't take every bit of advice they give, specially regarding to mechanics (WD40 is definitely NOT a chain lube). Specifically in this case, the data sample is way too small to be meaningful.

FullGas wrote:

Obviously I'm talking about rotation. If you look at your cranks like a clock the pushing down part of the stroke goes from 1 to 5 o'clock, therefore 40%. Another benefit you can get from a smooth pedal stroke is better balance and bike handling.

I love the GCN guys as much as the next guy. But, I wouldn't take every bit of advice they give, specially regarding to mechanics (WD40 is definitely NOT a chain lube). Specifically in this case, the data sample is way too small to be meaningful.

But you have two legs.

I am not saying the GCN guys are always right, but this wasn't just them giving 'advice', it was a test of lactate levels, heart rate and VO2 max.

Having one test subject is obviously not scientifically conclusive (as GCN themselves pointed out), but if there was a massive difference in pedalling efficiency then it would have become apparent.

danjoyce wrote:

Having used lots of different pedal systems, I now just use SPDs for everything, even time trialling and hill climbing. I do okay. If the shoe sole is stiff enough, pedal platform is princess and the pea stuff.

I just use SPD for everything too. I've tried SPD-SLs too.

I know Global Cycling Network did a lab test using clipless and flat pedals and found no difference between them, so I find it very difficult to believe there is a night and day difference between SPDs and Looks.

danjoyce wrote:

Having used lots of different pedal systems, I now just use SPDs for everything, even time trialling and hill climbing. I do okay. If the shoe sole is stiff enough, pedal platform is princess and the pea stuff.

I think so too, I'd love to see a test to see if there are any difference in power transfer. Even if there was, the ease of use and durabilty makes spds a much better choice for the majority of people.

danjoyce wrote:

Having used lots of different pedal systems, I now just use SPDs for everything, even time trialling and hill climbing. I do okay. If the shoe sole is stiff enough, pedal platform is princess and the pea stuff.

I'm with Dan too. The only time I ever use road pedals is when I'm going to be on the bike all day and even then that's only because I've got a really comfortable pair of Fizik road shoes that have a bit more give in the upper than my usual MTB shoes.

It's also worth remembering that SPDs come with a a lot of different platform options besides just the basic 525. There are touring pedals like the A600 - which is basically a road pedal that takes an SPD cleat, or my particular fave the M324 - single sided SPD on one side, flat metal cage the other - a great all-purpose commuter pedal.

Tony Farrelly][quote=danjoyce wrote:

It's also worth remembering that SPDs come with a a lot of different platform options besides just the basic 525.

i have a pair of xtrs that's done around 8k miles, the only bit of maintenance I've ever had to do was spray a bit of lube on one pedal as it wasn't clipping in as smoothly, after that they work like they are new.