Power to Weight Ratio



evanhyde

New Member
Oct 30, 2004
24
0
0
What is your power to weight ratio (watts/kg) and what Category do you race?

me: 4.5, cat 4
 
evanhyde said:
What is your power to weight ratio (watts/kg) and what Category do you race?

me: 4.5, cat 4

For any numbers to even begin to be useful, you need duration.

Altitude, type of powermeter, and height might also be helpful.
 
Squint said:
For any numbers to even begin to be useful, you need duration.

Altitude, type of powermeter, and height might also be helpful.
Generally I think of power to weight ratio as a 30 minute effort, but i guess that's because I just finished reading lance armstrong's war. so let's say 30 minute power.

as far as power meters, dont they all measure watts? I don't think I should have to specify your SRM power ratio or your Powertap ratio. if you live at altitude, what is your ratio at that altitude? if you live at sea level, what is it there?

height makes no difference

Basically I wanted to get a sense of people's general ratio's and see any correlation with their USCF category.
 
evanhyde said:
as far as power meters, dont they all measure watts? I don't think I should have to specify your SRM power ratio or your Powertap ratio.
SRMs measure further up the drive train than PTs. They typically read ~2% higher since there is less frictional drivetrain loss where the measurement occurs.
 
frenchyge said:
SRMs measure further up the drive train than PTs. They typically read ~2% higher since there is less frictional drivetrain loss where the measurement occurs.

Not to mention the occasional posting by someone who got his or her numbers from a gym exercise bike or a $300 stationary trainer.
 
frenchyge said:
SRMs measure further up the drive train than PTs. They typically read ~2% higher since there is less frictional drivetrain loss where the measurement occurs.
That 2% is with my SRM's 3-5% error window, so I'm not sure how much it matters. anyways, I was not looking for a world-class scientific study, just a general power to weight ratio on whatever equipment people have available and wherever they happen to be using that equipment.

SO... frenchyge: if someone asked you how many watts/kilo you could sustain for 30 minutes, and you could only answer in a ratio-like number, what would you say?
 
Squint said:
Not to mention the occasional posting by someone who got his or her numbers from a gym exercise bike or a $300 stationary trainer.
Of course, I should have seen that right off the bat. When the OP mentioned SRM v. PT he grabbed my train of thought to that track as well.
 
I weight 59kg or 130lb. LT power (30 minutes TT interval) is 245w. Average HR (if you want to know) is around 179 to 180. My 5 minutes power output is 300w. Average HR is about 182.

whoawhoa said:
BlueJersey and evanhyde, do you mind sharing your mass/total power?
 
acoggan said:
http://www.cyclingpeakssoftware.com/profile.html

I believe that Ric Stern also has some general guidelines on his site...they might only be for longer durations, though.

Thanks. Towards the end of this page http://www.cyclecoach.com/downloadPages/?download=Calculate_your_MAP_zones&ext=.htm there's a list of MAP results for power to mass^0.67, and a ranking based on that for males, and some data for females. If you type in your MAP result your training zones and estimated powers for a variety of durations are calculated. It's all based on MAP.

Ric
 
If your bike weighed nothing and your output was 13W/kg then you would have about 17hp per metric tonne. Sounds like nothing but remember cars only produce 100bhp at top revs and dont necessarily translate all of that into the forward motion. Something to compare W/kg with though I suppose.

A W/CdA figure would be nothing like a car though :(
 
whoawhoa said:
BlueJersey and evanhyde, do you mind sharing your mass/total power?
77 kg, and my updated power (from a 22 minute time trial this afternoon) is 388 watts. So that is a power to weight of 5.0. (Probably would be around 4.8 if I extended it out to 30 minutes) again, using and SRM amateur.