"PRO" Cycling Discussion

Questions about bike hire abroad and everything light bike related. No off-topic chat please

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KWalker
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by KWalker

You guys are missing the point- they probably do not care about L/R balance as its a complete red herring. The units are probably valuable because they don't need a compact and standard SRM and swap cranks often in stage races. With Stages they can use the same arm regardless, making it easier to have power for every single stage.

Also, Stages accuracy during highly variable efforts probably doesn't matter as Sky does not race cross, do criteriums, or technical MTB races. It probably works just fine for what they need. Also, no need to worry about calibration and elevation.

Also for maintenance and transport it has got to be a world easier in terms of support required to monitor the battery life of units, when units have been calibrated, etc., which is an inherent flaw of SRM's design until they make a unit that has a user replaceable battery and is easier to user calibrate.

Regarding L/R balance, I've been monitoring mine for around 6 months with my P2M. In the meantime I've gotten fit adjustments of all sorts from a well-regarded fitter. The verdict? Despite my cleat being 5mm off on one side and having an asymmetric (as confirmed by x-rays) pelvis, my balance never gets worse than 48/52. Even with the tweaks the rides vary between 50/50 and 49/51 and during hard, anaerobic efforts it stays fairly linear. It really doesn't matter all that much nor is it really changeable. After months of adapting to position changes it looks like everything else is identical on my QA plots for similar rides.
Don't take me too seriously. The only person that doesn't hate Froome.
Gramz
Failed Custom Bike

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djconnel
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by djconnel

You prove my point: 2% variation in L-R balance. That's a 4% error off the top on total power. That's consistent with what I saw with DCRainmaker's data. If 4% power errors don't matter to Sky, then fine.

Suppose I'm looking at power to pace myself in a double century. 4% is good enough. I'm just using it to make sure enthusiasm doesn't get the best of me on early climbs.

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Tapeworm
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by Tapeworm

djconnel wrote:Expect riders to emerge from season with rippling muscles on left legs and atavistic, atrophied right legs due to biofeedback.


:lol: But as you said, a potential 4% (or potentially) more error of margin seems a step away from the team of "marginal gains".

I do think the Stages is an excellent unit though for a whole host of reasons mentioned above by KW, plus it's not that expensive. And LIGHT.
"Physiology is all just propaganda and lies... all waiting to be disproven by the next study."
"I'm not a real doctor; But I am a real worm; I am an actual worm." - TMBG

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bearsdidit
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by bearsdidit

It looks like the Sky guys are interested in using Strava for the KOMs!

DanW
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by DanW

You prove my point: 2% variation in L-R balance. That's a 4% error off the top on total power. That's consistent with what I saw with DCRainmaker's data. If 4% power errors don't matter to Sky, then fine.


No offence to KW but I don't think he is at the level of riding pro for SKY (correct me if I am wrong :D ). Based on my own highly unscientific observations, this 4% total error due to L/R imbalance with the Stages assumption is what I'd expect for an enthusiastic amateur, having an off day and maybe carrying a niggling injury to one leg. I would have thought this represents a very worst case error and certainly not something you'd see in a fit and healthy Pro. Total errors due to the one side assumption are therefore pretty low. For all we know the measurement error with Stages is half that of SRM or similar and both output the same power at the end of the day with the same overall uncertainty in the final number???

I do agree there is more potential for magnifying errors with Stages but it's unlikely to bother the Pros and if SKY adopt it then you'd have to assume they've given it some thought. You'd also think that if Stages are confident in their assumption they could publish some data which would be good to look at (rather than some vaguely similar looking power outputs on their website)

DartanianX
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by DartanianX

Finally a nice looking National Champions jersey.

Image

Still not kit for the Tinkoff Saxo Team. Plain Sportful kit for now.

Image

Sent from my Nexus 4 using Tapatalk

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djconnel
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by djconnel

Andy looks super-skinny for January. He was complaining last year as he's matured he's not been able to maintain as low an off-season weight. He looks almost anorexic in that photo.

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djconnel
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by djconnel

DanW wrote:
You prove my point: 2% variation in L-R balance. That's a 4% error off the top on total power. That's consistent with what I saw with DCRainmaker's data. If 4% power errors don't matter to Sky, then fine.


No offence to KW but I don't think he is at the level of riding pro for SKY (correct me if I am wrong :D ). Based on my own highly unscientific observations, this 4% total error due to L/R imbalance with the Stages assumption is what I'd expect for an enthusiastic amateur, having an off day and maybe carrying a niggling injury to one leg. I would have thought this represents a very worst case error and certainly not something you'd see in a fit and healthy Pro.


Maybe you're right -- maybe they compared it to SRM and it was fine. All I have is a few rides from DC Rainmaker, who's not a pro.

KWalker
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by KWalker

djconnel wrote:You prove my point: 2% variation in L-R balance. That's a 4% error off the top on total power. That's consistent with what I saw with DCRainmaker's data. If 4% power errors don't matter to Sky, then fine.

Suppose I'm looking at power to pace myself in a double century. 4% is good enough. I'm just using it to make sure enthusiasm doesn't get the best of me on early climbs.


If it's always 4%, then is still consistent right? Given that they were using O Sys with SRMs for years juuuust fine, which would have more error, shouldn't be a big deal.

I also wouldn't presume any error would be lower/higher than in a pro. It doesn't necessarily affect my gross efficiency. My power output is the same at 50/50 for lots of work as it is at 52/48 from the data I have. But again, it measures power from both legs, not just 1.
Don't take me too seriously. The only person that doesn't hate Froome.
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prendrefeu
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by prendrefeu

That Trek Factory Racing kit is, sadly, not surprising given the primary sponsor. I'm sure the fabric is stocked with tech, but the aesthetics are severely lacking.
Par for course but, moving on... best of luck to the Schlecks, et al., in getting their Grand Tour mojo back on.
Exp001 || Other projects in the works.

hotshot
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by hotshot

DartanianX wrote:Michael Hepburn wins Australian Elite TT title

Orica Green Edge go 1-2-3 as well with Luke Durbridge and Damien Howson rounding out the podium for OGE.

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Looks like OGE have the same design skin suit wise as Sky last year.

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They are similar to the Bioracer ones used by Sky and Tony Martin, but not exactly the same. same material but different paneling and cut to the 2 suits. From memory craft had suits very similar for sale last year.

xnavalav8r
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by xnavalav8r

djconnel wrote:Andy looks super-skinny for January. He was complaining last year as he's matured he's not been able to maintain as low an off-season weight. He looks almost anorexic in that photo.


Andy who?

xnavalav8r
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by xnavalav8r

prendrefeu wrote:That Trek Factory Racing kit is, sadly, not surprising given the primary sponsor. I'm sure the fabric is stocked with tech, but the aesthetics are severely lacking.
Par for course but, moving on... best of luck to the Schlecks, et al., in getting their Grand Tour mojo back on.



You have to admit, the Trek kit looks better than the Sky mesh bodystocking.

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Kjetil
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by Kjetil

DartanianX wrote:Finally a nice looking National Champions jersey.
:) Gone the Leopard atrocities. Time for Fabü to become Swiss national champion again.

Also, and sliding off topic: Where can I find (popular) science on the unimportance of left/right power balance? A fellow rider just shelled out on Garmin Vector pedals and is worried about 60/40. Would be nice lead him to facts.
Bianchi-Campagnolo

pastronef
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by pastronef


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