Shouldn't FTP calculations in Watts/KG take into account bike weight?

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Dogtrousers

Kilometre nibbler
Highest w/kg over what duration? Someone who excels at 5 minute climbs may not be the fastest on 4 hour alpine climbs.
Over 1 hour. By convention FTP is the power a rider can maintain over one hour.

That's why FTP in W/kg is no good to use as a predictor of speed or times in specific circumstances, unless we are talking about a one hour effort. FTP is just a metric for fitness. And FTP in W/kg is just a metric for fitness/fatness.

Thinking about it, when the race commentators on TV mention that so and went up such and such a climb at 6W/kg they aren't talking about FTP, which the OP is. They're talking about the rider's actual power output on that climb which, depending on the climb, may have been at or over or even under threshold. I think that's the source of some of the confusion in this thread.
 
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Ming the Merciless

There is no mercy
Location
Inside my skull
Over 1 hour. By convention FTP is the power a rider can maintain over one hour.

That's why FTP in W/kg is no good to use as a predictor of speed or times in specific circumstances, unless we are talking about a one hour effort. FTP is just a metric for fitness. And FTP in W/kg is just a metric for fitness/fatness.

Thinking about it, when the race commentators on TV mention that so and went up such and such a climb at 6W/kg they aren't talking about FTP, which the OP is. They're talking about the rider's actual power output on that climb which, depending on the climb, may have been at or over or even under threshold. I think that's the source of some of the confusion in this thread.

Indeed which means it can’t be used to predict who will be the fastest up any hill. Plus who does a test over an hour to see what their FTP is? It’s assumed the figure is what they could maintain over an hour, but who knows in reality, who has actually tried that?
 
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Dogtrousers

Kilometre nibbler
Indeed which means it can’t be used to predict who will be the fastest up any hill.
Not with any accuracy.

Although you can use it to have a decent guess. If you had two riders, say me and Tadej Pogacar, submit our W/kg FTPs without revealing our identities I think that you could predict with some certainty who would be fastest up any hill. :laugh:
 
Indeed which means it can’t be used to predict who will be the fastest up any hill. Plus who does a test over an hour to see what their FTP is? It’s assumed the figure is what they could maintain over an hour, but who knows in reality, who has actually tried that?
Anyone who's raced a 25 give or take.
 

bridgy

Legendary Member
Location
Cheddar
Which means we won’t know anyones W/Kg for that hill, plus if we did and two riders had the same all out W/Kg for that hill, the heavier of the two will be faster up the hill. You may even have a case where the lighter person edges it on W/Kg but they are not fastest up the hill.
Well, you would know peoples w/kg if you measured it.

And yes, assuming bike weight etc being equal, if the heavier rider matches the lighter rider's w/kg they would probably be slightly faster. The problem is, this can get increasingly hard to do, particularly on longer climbs as the heavier rider needs to put out more raw watts - and if the weight difference between riders is large this can be a LOT more watts to maintain.

Anyway, I just said the person with the highest w/kg would probably get up the hill quickest, which is true (assuming roughly similar bike weights etc of course) even if there might be the odd exception.

And if you want to increase your own personal climbing then your w/kg would be a very important and useful calculation to focus on and try to improve, as you'll go faster up hill if your w/kg goes up.

So yeah, it's not the be all and end all, but it's still a useful/important calculation for cyclists wanting to improve their climbing in particular. Not sure what you have against it really, it's just a useful metric!

Edit: Reading your other posts above, I think we might be at odds with each other because you're meaning FTP when you mention w/kg? I was just replying based on the use of the term w/kg - if you're meaning "FTP in W/kg" then yes, that's less of a predictor for speed up a specific hill I agree
 
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