Who needs a power meter when VAM is free?

[@Montezuma0]

Is the W/kg including the bike weight or just the rider weight? Seems like it should include the bike weight to make it more accurate.

[@blinzi69]

what about wind sir?

[@rodolfogiogervasio2169]

Does the formula take into account external weight of the rider, such as weight of the bike etc?

[@josschreur6992]

In a flat country as the Netherlands its not much off use ;)

[@Cloxxki]

Wat werkt hier goed met bescheiden budget? Ik rijd vooral MTB, maar ook vooral op de weg met dikke slicks.

[@ByStrumbah]

But that formula must have been used using pro level bikes, which are lighter, so faster, than normal bikes. So in this formula, the weight of the bike is supposed to be the weight they used at that time?

[@marlondecarne7118]

What about flat road?

[@ifeeltheneedforspeed]

Doesn't work on flat roads and also a bit inconsistent on short punchy hills too. It works best on long sustained climbs

[@discbrakefan]

Watts per kilo isn’t as relative on a flat road since weight has minimal effect and wind resistance takes over. VAM is totally useless since you’re not climbing.

[@poxcr]

Good luck trying to use VAM on the flats or riding an indoor trainer.

[@ifeeltheneedforspeed]

Pretty useless going downhill too

[@ArbaritorCycling]

Cool video¡¡¡ i´m going to use the info, thanks¡¡🚀🚀🚀

[@sillypuddystl2907]

Very interesting.

[@CoreQ]

people needs power meter because we don't have to do anything but reading the data that's already calculated.

[@tristanguillemette6777]

Hey, cool video! Could you possibly share me your excel sheet ahah?

[@jamesward2141]

Yea garmin and Strava do this already...

[@ifeeltheneedforspeed]

Oh cool. I knew they did vam but didn't know they calculated watts/kg too. Will look for the field next time I ride outside, whenever that'll be 🤷‍♂️

[@aaron___6014]

How do I use it? Please provide a link.

[@NicholasNRB.Barnett]

So hard to miss the LIP SMACKING!!! Aahhh! Stop it!

[@thprodctions]

What about drag?

[@ifeeltheneedforspeed]

There are generally 4 forces at play - wind, rolling resistance, drivetrain and gravity. The impact of rolling resistance and drivetrain is relatively constant, but drag increases exponentially as speed increases. Conversely at slower climbing speeds, the effect of gravity far outweighs the impact of wind resistance. The steeper the hill, the less of an impact it has. Reminds me I need to share the spreadsheet

[@thprodctions]

I mean in the VAM formula you showed wind resistance is not considered. In your power data wind resistance is taken into account since this is the primary force you are combating when cycling at speed as indicated

[@ifeeltheneedforspeed]

@@thprodctions you're right, i showed a simplified equation that uses a "gradient factor" that hides some of this complexity. This is a precalculated approximation based on a number of assumptions on altitude (air density) and rolling resistance. The reason why I use the approximation is the cubic equation is basically linear for the range of gradients that typically go from 0-15%. This dramatically simplifies the calculations rather than having to solve a complex cubic equation, especially when at threshold! The full equation is explained better by the climbing cyclist : theclimbingcyclist.com/gradients-and-cycling-how-much-harder-are-steeper-climbs/

[@thprodctions]

Thanks Derek, you got my subscription