wattbike 'speed'

mattmaximus

Does anyone know what conditions a wattbike assumes to achieve its speed readout?

I'd be interested to know whether anyone has found a correlation between, say, the time for 10 miles on a wattbike and the same distance for real at the same wattage.

bahzob

I think its around about what a track rider could do for the power, so quite streamlined but not tri.

That said its a pretty irrelevant figure since the bike has no data on weight, bulk, environment and other factors that would affect it.

I think it's only really there to maintain consistency with other indoor trainers and it would be strange not to display it given it measures time/distance. (Distance ofc is similarly arbitrary but nice to have an alternative interval target/measure to time/kj.)

(The comments on power>speed are not specific to Wattbikes. They also apply to real bikes. Even same rider, same bike, same course will record a range of speeds depending on the fine details of how they are positioned, state of the road and wind direction)

mattmaximus

Thanks - don't worry, I wasn't under any illusions about the unreliable nature of speed/distance data; I guess I was just curious. The algorithm was presumably based on some kind of real world data. Track cycling would make sense. I was also intrigued to know whether those wattbike 'speeds' could actually be achieved at the given wattage and, if so, what conditions were necessary. I guess I'll just have to save up for a pm so I can find out!

bahzob

Np. If you have access to a Wattbike I'd advise taking a look at the polar view and be interested in how you find it.

More info about it here if you aren't already familiar with it http://wattbike.com/uk/guide/cycling_tests/pedalling_technique_test/what_the_polar_view_shapes_mean

Alex_Simmons/RST

mattmaximus wrote:

Does anyone know what conditions a wattbike assumes to achieve its speed readout?

I'd be interested to know whether anyone has found a correlation between, say, the time for 10 miles on a wattbike and the same distance for real at the same wattage.

"Speed" on a Wattbike is dependent on the air brake and mag resistance settings chosen, of which there are multiple of each, hence the speed you'll get from a given power output could be just about anything.

mattmaximus

bahzob wrote:

I'd advise taking a look at the polar view and be interested in how you find it.

I've been interested in the polar view, particularly that I really struggle to maintain even balance between left and right feet when pedalling easily. When I do something more intensive and then check the data afterwards I find it's much more balanced. :?

I am thinking that if I can round out the stroke a bit more (at the moment i'm somewhere between a jaunty figure 8 and a jelly baby) then it ought to help. Harder to achieve than I thought it would be, though!

mattmaximus

Alex_Simmons/RST wrote:

"Speed" on a Wattbike is dependent on the air brake and mag resistance settings chosen, of which there are multiple of each, hence the speed you'll get from a given power output could be just about anything.

Hi Alex
Yes, I think this was basically my point, albeit not expressed very well. I was looking for some context from those in a position to compare real world data with the wattbike figures. I'm not quite sure how to go about using the feedback from the wattbike when I go out on my road bike, nor do I have any clear idea about what the numbers mean I can be looking to achieve. All in all, the more I think about it, the more I realise I don't know what I'm doing :roll:

Alex_Simmons/RST

mattmaximus wrote:

Alex_Simmons/RST wrote:

"Speed" on a Wattbike is dependent on the air brake and mag resistance settings chosen, of which there are multiple of each, hence the speed you'll get from a given power output could be just about anything.

Hi Alex
Yes, I think this was basically my point, albeit not expressed very well. I was looking for some context from those in a position to compare real world data with the wattbike figures. I'm not quite sure how to go about using the feedback from the wattbike when I go out on my road bike, nor do I have any clear idea about what the numbers mean I can be looking to achieve. All in all, the more I think about it, the more I realise I don't know what I'm doing :roll:

The only feedback from wattbike that would be relevent are power output and perceived exertion. Forget speed.