Mavic’s £900 Comete cycling shoes save 4.2 watts per pedal stroke

Nicolas_GREGOIRE wrote:

Hello,

 

My name is Nicolas GREGOIRE (you can call me Nico) and I am in charge of biomechanics testing for MAVIC. I would like to offer more details and some clarity on the explanation of our claim of saving 4.2 watts per pedal stroke.

 

The goal of one of our tests was to maintain 250 watts for the duration of the test. If we look at the instantaneous power during the pedaling cycle, there is a variation between 70 watts (through the “dead point”) and 400 watts (when the crank is around 90° - in the power phase). With the Comete Ultimate shoes, we discovered less variation (4.2 watts less) due to a more efficient stroke through the dead zone. So, to maintain 250 watts, you require less effort through the power phase. There will be a much more detailed explanation coming in April on mavic.com in our “Engineers Talk”. As we’ve made some bold claims, we are offering you the opportunity to experience this incredible connection to the bike for yourself before you purchase the shoes. At all Comete Ultimate dealers you can reserve a pair for testing through our “Riding is Believing” program starting in mid-April - https://www.mavic.com/en-int/riding-is-believing.

 

Thank you again for the discussion!

More responses like this please.

Nicolas_GREGOIRE wrote:

Hello,

 

My name is Nicolas GREGOIRE (you can call me Nico) and I am in charge of biomechanics testing for MAVIC. I would like to offer more details and some clarity on the explanation of our claim of saving 4.2 watts per pedal stroke.

 

The goal of one of our tests was to maintain 250 watts for the duration of the test. If we look at the instantaneous power during the pedaling cycle, there is a variation between 70 watts (through the “dead point”) and 400 watts (when the crank is around 90° - in the power phase). With the Comete Ultimate shoes, we discovered less variation (4.2 watts less) due to a more efficient stroke through the dead zone. So, to maintain 250 watts, you require less effort through the power phase. There will be a much more detailed explanation coming in April on mavic.com in our “Engineers Talk”. As we’ve made some bold claims, we are offering you the opportunity to experience this incredible connection to the bike for yourself before you purchase the shoes. At all Comete Ultimate dealers you can reserve a pair for testing through our “Riding is Believing” program starting in mid-April - https://www.mavic.com/en-int/riding-is-believing.

 

Thank you again for the discussion!

Guessing minimal cycling shoes will be the nu nu if this catches on. We've had the efficiency in range of motion debate in running for aeons now - barefoot v minimal v cushioned. 

Looking at my first pair of Bonts, the A-3, there's no way that shoe can provide an efficient range of motion for a pedal stroke. Think about the small muscles in your foot that also push on the downstroke, those are almost all totally negated by the boat-like structure of the shoe. 

I'd like to try these Mavics. Pay 900 for the priviledge, never. But definitely up for better cycling shoe design. Got some Empire SLX's at the moment which are much better than Bonts, but definitely we're not really at a stage where cycling shoes are as advanced as running shoes. 

Guess with running there's only really shoes to get techy about, besides the clothing fabrics, which is why the shoes are genuinely really amazing these days. Loads of options and a good store can fit you with in house scanning equipment in minutes. With cycling you get a boat like thing, or some traditional bowling shoe shaped thing and everyone's accustomed to that. 

Good to see Mavic pushing it a bit further with the biomechanic angle, not just comfort/weight.

Nicolas_GREGOIRE wrote:

The goal of one of our tests was to maintain 250 watts for the duration of the test. If we look at the instantaneous power during the pedaling cycle, there is a variation between 70 watts (through the “dead point”) and 400 watts (when the crank is around 90° - in the power phase). With the Comete Ultimate shoes, we discovered less variation (4.2 watts less) due to a more efficient stroke through the dead zone. So, to maintain 250 watts, you require less effort through the power phase. There will be a much more detailed explanation coming in April on mavic.com in our “Engineers Talk”. As we’ve made some bold claims, we are offering you the opportunity to experience this incredible connection to the bike for yourself before you purchase the shoes. At all Comete Ultimate dealers you can reserve a pair for testing through our “Riding is Believing” program starting in mid-April - https://www.mavic.com/en-int/riding-is-believing

Buuuut... you're still putting out 250 watts, so that actual power is the same. That energy/power still has to go in from the rider. Even if the variation between peak and dead point is lower, it's not actually saving any energy. It may be more biomechanically efficient to produce 250 watts this way, but that's not at all quantified by your measurements. The claim is still nonsense.

Bob Wheeler CX wrote:

At what point exactly, did cycling become a hobby for shameless yuppies?

Janurary 1st 1997

beezus fufoon wrote:

Bob Wheeler CX wrote:

At what point exactly, did cycling become a hobby for shameless yuppies?

Janurary 1st 1997

Janurary 1st 1887 - you got the century wrong.

Jackson wrote:

Everyone's being pedantic. I'm sure they mean 4.2W at steady state (and they probably tested at 40km/hr to inflate the pathetic W figure as far as reasonable). Probably the worst bang for your buck in TT equipment but don't buy a pair. I kinda like the Robocop meets 60 year old German bike tourist in SPD sandals aesthetic though. 

Not pedantic at all IMHO. If you're going to make a technical claim about a very expensive product, you should at least get it right. They're talking nonsense and they've been called on it. 

You're making massive assumptions about what the figure is meant to mean, and if you spent £900 on a pair of shoes on the basis of such assumptions, you'd almost certainly be very disappointed.

Agree the aesthetics are quite interesting though.

DaveE128 wrote:

 

Not pedantic at all IMHO. If you're going to make a technical claim about a very expensive product, you should at least get it right. They're talking nonsense and they've been called on it. 

You're making massive assumptions about what the figure is meant to mean, and if you spent £900 on a pair of shoes on the basis of such assumptions, you'd almost certainly be very disappointed.

Agree the aesthetics are quite interesting though.

How's this hypothetical disappointed Fred who's just bought his £900 shoes going to measure his 4.2W power saving then? With his SRM (accurate to +/-2.5%)? 

We all know technical claims in the bike industry are mostly nonsense, it's all part of the fun. 

Jackson wrote:

DaveE128 wrote:

 

Not pedantic at all IMHO. If you're going to make a technical claim about a very expensive product, you should at least get it right. They're talking nonsense and they've been called on it. 

You're making massive assumptions about what the figure is meant to mean, and if you spent £900 on a pair of shoes on the basis of such assumptions, you'd almost certainly be very disappointed.

Agree the aesthetics are quite interesting though.

How's this hypothetical disappointed Fred who's just bought his £900 shoes going to measure his 4.2W power saving then? With his SRM (accurate to +/-2.5%)? 

We all know technical claims in the bike industry are mostly nonsense, it's all part of the fun. 

It's the 'per stroke' shit that people are mainly laying into. It's even more pointless and inaccurate than just claiming a 4.2W saving.

Jackson wrote:

DaveE128 wrote:

 

Not pedantic at all IMHO. If you're going to make a technical claim about a very expensive product, you should at least get it right. They're talking nonsense and they've been called on it. 

You're making massive assumptions about what the figure is meant to mean, and if you spent £900 on a pair of shoes on the basis of such assumptions, you'd almost certainly be very disappointed.

Agree the aesthetics are quite interesting though.

How's this hypothetical disappointed Fred who's just bought his £900 shoes going to measure his 4.2W power saving then? With his SRM (accurate to +/-2.5%)? 

We all know technical claims in the bike industry are mostly nonsense, it's all part of the fun. 

https://en.wikipedia.org/wiki/Accuracy_and_precision

srchar wrote:

You can't save "4.2 watts per pedal stroke". You can save 4.2 watts, or you can save 4.2 joules per pedal stroke.

...which just proves that this bollocks comes from the marketing department rather than anyone with even a passing interest in engineering.

Not necessarily. My take is that the reasearch came up with a saving of up to 4.2W over a pedal stroke. But that the hypothetical savings would actually be less than that 4.2J. See, I'm going to guess that those "savings" were over real or hypothetical (Chris Hoy) maximum of 3,000W over one revolution at 120rpm, so something like .5s, versus a much smaller number over a full second (say, 2.8W on 2,200W). So the engineering guys went with the larger headline number, "for upto one (360 deg - they're being conservative, after all ) pedal stroke". The marketing guy at Mavic edited out the "upto", and abra cadabra, buy these shoes and you're getting all your electronics powered for free (well, £900) over the entire IndiPac.