Power/Speed

[fraz101]

I have noticed recently that most people who are stronger than me within my local club are able to go faster with less power output. For me to achieve the speed they do in general terms means I would have produced a lot more watts than they do to essentially you achieve the same speed. I do not understand this? My only conclusion is people are more aero so go quicker without using as many watts.

What are your thoughts on this?

 

[DogmaStu]

I have noticed recently that most people who are stronger than me within my local club are able to go faster with less power output. For me to achieve the speed they do in general terms means I would have produced a lot more watts than they do to essentially you achieve the same speed. I do not understand this? My only conclusion is people are more aero so go quicker without using as many watts.

What are your thoughts on this?

Watts/kg and CdA (aero drag) will definitely come into it on the road. On a track it is generally pure power but road is typically not flat and subject to varying weather.

As such, a rider pushing out 300W who is 65kg will have an advantage over someone pushing out 350W but who is 80kg. Similarly, a rider with a greater drag co-efficient will need more watts to propel themselves forward, more so in increasingly windier conditions.

Riding technique will play a part - how aero you make yourself. Aero-bikes are generally more 'aggressively' designed to force a more aero position from the rider, hence the greater gains, more so than the bike itself can offer.

I can sprint pretty well but I don't have a huge amount of power, less than 1100W these days at 55yrs old, but...I weigh 63kg and have a low CdA. I regularly beat much larger, more powerful guys.

 

[wafter]

Firstly is this all predicated on accurate power values (i.e. those measured at the crank by a decent power meter, not some nebulous figure conjured up by a cycle computer based on tertiary variables and assumed values)?

Assuming the figures can be believed difference will be due predominently down to aero drag (drag coefficeint and frontal area of rider and bike), and to a lesser extent system mass and tyre rolling resistance.

 

[Ridgeway]

Strava watts ?

Unless comparing accurate PM data then too many variables to consider.

The only thing i really compare myself to is myself on some long climbs where most other factors have less influence, just me and gravity.

 

[TheDoctor]

Sheer bravado, cunning and shameless wheel-sucking also play a part. When I was riding with our local CTC, my mission was to be first to the bar at pub stops. If that meant bunny-hopping the steps and riding in through the front door, so be it!

 

[Ming the Merciless]

Drafting, you can go the same speed for about 30-40% less watts. Chain gangs often have one or two strong riders on the front and weaker riders behind in the draft. It’s why road club ride in close formation.

 

[presta]

less power output

Measured how?

 

[fraz101]

Measured by power meter and not drafting (solo loops)

 

[presta]

Measured by power meter and not drafting (solo loops)

Are all those you're comparing with using power meters too? Are the differences big enough not to be accounted for by instrument accuracy?

If the differences are real, then as said above, wind resistance and (for acceleration & climbing) weight are your main candidates.