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35 votes

What applications exist for bicycle power, besides propulsion?

Bicycles are simply a method of generating rotational mechanical movement from biological sources. That rotational energy can be used for anything where a motor would be used. The items below have all ...
Criggie's user avatar
  • 127k
18 votes

Is it possible to burn only ~850 cal. on 1.5h / 20 km fast bike ride?

Since the other answers and comments were discussing only your bike trip, I will tackle on your hike values and show why they are probably incorrect. First of all your activity wasn't a hike, but a ...
sheep's user avatar
  • 181
15 votes

What is the drag / power lost to a safety flag?

If the pole is a flexible one, you can do the following: Choose a windless day Ride past a second person at a known speed Let the second person take a picture while you pass Repeat immediately in the ...
cmaster - reinstate monica's user avatar
15 votes
Accepted

Understanding e-bike power/torque

Very quick answer - the torque numbers that are quoted are maximum torque values which do not correspond to maximum power. Power = torque × rotational speed, so, at slow speeds the motor unit can ...
Argenti Apparatus's user avatar
15 votes

What applications exist for bicycle power, besides propulsion?

Foot operated sewing machines were very common before electric machines appeared. Unlike hand operated machines they allow using both hands for cloth adjustment, and other energy sources like rotating ...
nightrider's user avatar
  • 7,879
13 votes
Accepted

How to convert calories to watts on Strava rides?

Turning my comment into an answer: Watts in a bicycling context are usually measured (or estimated) as mechanical power at the wheel (or crank). Calories burned are the (estimated) total input energy. ...
Michael's user avatar
  • 28.1k
12 votes
Accepted

What use does a Heart Rate Monitor have if you have a Powermeter?

There is only one occasion I would consider use of HRM has priority over a power meter (or indeed no monitor at all and simply using perceived exertion), i.e. your doctor or cardiologist has ...
alexsimmons's user avatar
  • 2,445
12 votes

Is it possible to burn only ~850 cal. on 1.5h / 20 km fast bike ride?

The bicycling calories sound about right (maybe a bit too high, but assuming a relatively bad bicycle and higher moving speed between breaks it could work). I think it’s your walking calories which ...
Michael's user avatar
  • 28.1k
12 votes

Is there publicly available data on riders' critical and maximum power?

Getting data on professional riders is harder now than it used to be: in the past, teams and riders would sometimes post their data on Strava or in WKO format. I suspect, but do not know, that this ...
R. Chung's user avatar
  • 14.2k
11 votes

What use does a Heart Rate Monitor have if you have a Powermeter?

You can tell when you are knackered. Power indicates your actual output. With a baseline of previous power and HR data, you can establish a model for what you should be able to do. When your ...
Deleted User's user avatar
11 votes

What are (a) the source of and (b) the justification (e.g. experimental) for the concept of "normalized power" used in physical endurance training?

My understanding is that high-intensity efforts are disproportionately taxing, and NP is a way of reflecting that. That is, if you went for one ride where you maintained a steady 75% FTP output, and ...
Adam Rice's user avatar
  • 30.1k
10 votes

How much faster can my commute be if I use a power meter?

With that many interruptions your own performance is unlikely to make much difference to your commute times. Sprinting for the lights, when safe, is much more likely to help. If it's mostly stop signs ...
Chris H's user avatar
  • 60.2k
10 votes

What are (a) the source of and (b) the justification (e.g. experimental) for the concept of "normalized power" used in physical endurance training?

Focusing more on the empirical part of the question, consider the link that R. Chung gave in his first comment to Adam Rice's answer. That's the introductory chapter to Andrew Coggan's book, training ...
Weiwen Ng's user avatar
  • 32.8k
10 votes
Accepted

How can consumers test if their power meters are accurate, and how should we address discrepancies?

A watt is a Newton-meter per second, so testing accuracy requires only that you be able to impose a known force or load over a known distance in a known amount of time. That said, different power ...
R. Chung's user avatar
  • 14.2k
9 votes

Is the real world experience of riding a light bike understated by physics-based calculators?

The physics model of cycling power and speed has been validated in the real world. Two examples are this and this. The model embedded in Analyticcyling.com's online calculator is based on these two ...
R. Chung's user avatar
  • 14.2k
9 votes
Accepted

What is the difference between a speedometer and a power meter in terms of performance measurement?

Can't I just measure my speed and compare it against my last run and see if I've done better? Yes, but it's only directly comparable if the wind (and surface, and traffic ... but particularly wind) ...
Useless's user avatar
  • 3,017
9 votes

Garmin watch as a power meter

There may be some confusion with terminology here. A power meter measures power, usually by measuring the strain in some drivetrain component (i.e. how much it flexes when pedaling). You need to ...
Weiwen Ng's user avatar
  • 32.8k
9 votes

What is the maximum watt per kg a human can sustain?

Wilson, in Bicycling Science has a plot that's not quite what you're looking for but very close. Closer than it looks at first, I believe. click for full size The downside of this is that it isn't ...
Chris H's user avatar
  • 60.2k
9 votes

Power and climbing speed

The answer to your "is that roughly right?" question is: yes, roughly. You're essentially asking for a relationship between watts/kg and VAM (velocità ascensionale media, a term coined by ...
R. Chung's user avatar
  • 14.2k
8 votes
Accepted

Power Output at different Air Densities

Just coming back to this question as there are a few considerations. The OP only mentioned (barometric) air pressure and not necessarily altitude. I'll start with barometric pressure only and come ...
alexsimmons's user avatar
  • 2,445
8 votes

Power Output at different Air Densities

The following chart can be found in an interesting article on Training Peaks blog. From this you should be able to adjust your power level occordingly.
Andy P's user avatar
  • 18.3k
8 votes
Accepted

What's the difference between power meter and bike computer?

A 'bike computer' is a generic term for everything from a simple wheel sensor giving distance and speed, to an all singing all dancing computer that measure cadence, speed, altitude, heart rate, ...
mattnz's user avatar
  • 51.1k
8 votes
Accepted

Campanolo record power meter crank with veloce crankset

No. The Veloce crankset (assuming it's a 2011+ version) uses Campy's Power Torque system to attach the left crank arm. The Centaur crankarm offered by Stages uses Campy's Ultra Torque design, as do ...
Andrew Henle's user avatar
  • 10.7k
8 votes
Accepted

Most effective > 200 mile ride training

I did a ride of this length solo in March this year. I designed a route to suit me (not flat, not steep), and intended to be quick (I was aiming for under 21 hours). At 400km it was a tough day, but I ...
Chris H's user avatar
  • 60.2k
8 votes
Accepted

Why are electric bikes ranked on torque ratings?

Addressing just the actual question as stated to avoid a 3,000 word essay: With this in mind, how to interpret the advertised torque for a bike with a mid-drive hub, since it's heavily dependant on ...
Affe's user avatar
  • 1,225
8 votes

Is it possible to burn only ~850 cal. on 1.5h / 20 km fast bike ride?

Using this calculator we can estimate how much power you needed to produce to maintain your average speed of 20.26 km/85 min: I get 38 W, although I might have some of the conditions wrong. We can ...
Adam Rice's user avatar
  • 30.1k
8 votes

How to convert calories to watts on Strava rides?

Minor detail for the general audience: the ride in question lacks actual power meter measurements. It's pretty likely that the cyclist in question wanted to keep her power meter data off Strava, as ...
Weiwen Ng's user avatar
  • 32.8k
8 votes
Accepted

Giant power meter left/right balance

Typically, we don't need to pay too much attention to left/right balance because it's not clear that 50/50 is the optimal balance to aim for. Many of us have a slight imbalance. The advice isn't ...
Weiwen Ng's user avatar
  • 32.8k
8 votes

What applications exist for bicycle power, besides propulsion?

Bike-powered smoothie makers are a thing you can rent or buy. They're most often seen at events promoting science/engineering careers to kids, or sustainable travel. Bike-powered electrical ...
Chris H's user avatar
  • 60.2k
8 votes
Accepted

Accuracy of pedal-based power meters when used with pedal extenders / pedal spacers

I've emailed Favero about this, but this reddit thread features a fairly recent answer from their helpdesk (11 days ago when I initially wrote this). “As far as the Look version is concerned, we ...
DoNuT's user avatar
  • 4,496

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