[-dustin]

i was thinking the other day, while riding my new wheels...

let's say Joe Blo puts out ridiculous power, but he's all over the road, not-so-stiff shoes, tires under inflated, weak bb, wheels that flex like wet noodles, etc etc. at the end of the day, is his lack of attention to other variables hurting him to a point that a weaker rider would take him out?

why not take power efficiency into account? is it so minute that it doesn't really matter?

 

[loco-gringo]

Power is only as effective as it's translation to the ground. If someone squirrels all over on a climb, a weaker more efficient rider may fare as well. You are only as good as your form, all variables included.

 

[-dustin]

I guess there's just no reliable way to measure efficiency? seems like taking into account wattage, HR, speed, and everything else a Garmin and SRM spits out, some sort of formula could be contrived to estimate efficiency.

 

[MtnbikeMike]

Well, the problem with measuring efficiency is that you would need to measure the rider's power at their foot and at the tire. I don't think that would be really possible. I suppose you could add up the efficiency values for each component between the rider and the road....but someone would have to test those things.

 

[ire]

The closest thing I've seen to a study about efficiency is the info put out about hybrid bearings and the amount of watts you save by using them vs conventional steel bearings.

 

[SuspectDevice]

The losses you mention are fairly inconsequential, or in some cases, not losses at all.

There is no loss in power production or delivery from flex in a bb spindle or frame, for instance. Stiff shoes are inferior to shoes that have flex from an ergonomic standpoint, and a physiologically optimal amount of flex does not hinder power production or transmission. Stiffer wheels have no impact on power transfer, and a negative impact on comfort and handling.... The list just goes on from there.... Integrated seatmasts (bull****), 31.8 bars (bull****),bigger chainrings for timetrials (small wang compensation).

Lighter/stiffer is a fad driven by marketing, and not anything based in science. There is such a thing as "too-stiff" and it seems to be something that many of the major manufacturers are striving for to flex the wangs of their collective Asian manufacturers capacity....

At the most extreme ends of cross-chained filthy drivetrains you are looking at 2% losses due to friction. The majority of the losses (25% for a skilled cyclist, and higher for a neophyte) in the human-bicycle system are metabolic. Stiffer cranks aren't going to make the Krebs cycle more efficient, it not as hot outside, or increase oxygen carrying capacity....

Marketers and designers in the cycling industry by and large need to be pulled out into the street and whipped bloody with their own bull****. When the sunday-morning Armstrong wannabe crowd with deep pockets dries up, they will have priced and hyped themselves out of jobs, and driven away lots of people who could have become life-long cyclists with their soul-sucking hype and misinformation masquerading as hype and science.

 

[Westy]

I've always thought "stiff enough" was good enough. A flexing crank will still return the energy it absorbed back into the drive train. Same with chainstays and BBs. Not stiff enough steers you into the ditch when you sprint. It might not feel as snappy but that power is still going to the wheels.

 

[ire]

Marketers and designers in the cycling industry by and large need to be pulled out into the street and whipped bloody with their own bull****. When the sunday-morning Armstrong wannabe crowd with deep pockets dries up, they will have priced and hyped themselves out of jobs, and driven away lots of people who could have become life-long cyclists with their soul-sucking hype and misinformation masquerading as hype and science.

The deep pockets will always be there, around here roadies tend to be successful businessmen, lawyers, etc. They'll be there every Sunday morning with their Madrone and Latte