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Handlebar pitot

For measuring bicycle airspeeed
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Whilst cycling across fife with a stiff wind blowing in off the North sea today, I mused upon the measurement of bicycle speed. Most bike computers measure the speed over the ground, by counting wheel rotations; some also use GPS magick and also are able to measure altitude and therefore amount and rate of climb - a much more significant factor in bicycling action. But wind is a huge factor in bycycling, and so it would I suggest be more useful to know one's airspeed than one's groundspeed.

So, a long pole is mounted on the handlebars, with a pitot tube at the end, connected to an air speed indicator. The pitot might also be pivoted with a little vane, so that the relative wind direction is also indicated. To allow for post-ride analysis and pub boasting, a clockwork pen-trace can record direction and airspeed on a little reel of paper.

pocmloc, May 04 2011

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       Will that allow the defining of a ratio of speed regarding existing windspeed, for example, three sheets to the wind?
Ian Tindale, May 04 2011
  

       If you're arguing that a headwind makes cycling harder (which it does) and that therefore you should record a wind-adjusted speed, it is logical that you should also adjust the speed for other factors which make cycling easier or harder, such as incline and road smoothness.
hippo, May 04 2011
  

       There are now hubs that measure power, which corresponds to adjusted-for-everything speed, in a sense.
spidermother, May 04 2011
  

       Must be airspeeed is like airspeed, only going really really faaaaast.
RayfordSteele, May 04 2011
  

       // factors which make cycling easier //   

       Ah, ha, ha, ha!   

       [+]
baconbrain, May 04 2011
  

       // cycling across fife //   

       No doubt your environment alone would be a considerable spur to greater efforts. Leaving Fife by the most expeditious means is well known and documented social phenomenon. It is an undeniable fact that several of the most ambitious civil engineering projects in the last 150 of your years, including bridges over the Forth and Tay, were initiated with the noble intent of assisting people to leave Fife more rapidly.   

       At the low air velocities involved, a pair of rotary anemometers mounted at right angles in a horizontal plane might well give more useful and accurate data than a pitot, and would be more resistant to effects caused by environmental factors, such as icing (Prevalent in Fife throughout the year), and wasps building a nest in the ports. Special nasty yellow-and-black tartan wasp, with a real attitude problem. Yuk.
8th of 7, May 04 2011
  

       Whilst the pitot tube is a good idea I was thinking perhaps some magnets, a coil of wire and a nicad battery would be absolutely essential to, err....to measure the distance, of course.
not_morrison_rm, May 04 2011
  

       //At the low air velocities involved// You have never cycled across Fife, have you?
pocmloc, May 04 2011
  

       Thankfully, no. But we are conversant with the details of the psychiatric reports and in many cases autopsy findings of many who have tried.   

       For the purposes of generating a generally applicable specification it may be advantageous to exclude some more extreme cycling environments from the data set, includin polar regions, the surface of your moon, and Fife - which is notable for being the predominant bias factor; a bleak, windswept hostile wasteland, inhabited by surly incomprehensible drunks created specifically to reinforce the stereotypes found in Ian Rankin's novels.   

       Fife is like Hell, but with the addition of compulsory haggis, and a less welcoming attitude to newcomers.
8th of 7, May 04 2011
  
      
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