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Cyclecomputer argument!!!(8 posts)

Cyclecomputer argument!!!CRM
Jul 9, 2001 2:18 PM
Can anyone with more scientific sense than me (and my idiot friends) weigh in on this very serious matter? If two people go on a ride and one does the climbs faster than the other, will his cyclocomputer show a faster avg. speed at the end of the ride?

To expand it a little, what if the faster climber turned very short, very slow circles at the tops of the climbs while waiting for the slower climber?

And lastly, why is it if four people go on the exact same ride and use the same computer, they inevitably will all show a different distance at the end of the ride?

Thanks for the opinions!
simple mathmr_spin
Jul 9, 2001 3:12 PM
What's the argument? The formula is quite simple:

average speed = distance / time

If one rider does a specific distance (climbing or not) in less time than another rider, the first rider will have a higher average speed.

Turning slow, short circles increases the distance by a small amount but the time by a large amount, which will lower the average speed. (Hint: want a higher average speed? Don't do that! Or disconnect the computer first.)

Finally, assume four people ride identical bikes with identical computers all calibrated correctly. You'll still get different numbers, because the four people won't ride the exact same path. Even minute differences in distance, such as how sharp you turn corners, add up over time.
cyclecomputer differencesMel Erickson
Jul 9, 2001 3:33 PM
Differences are mainly due to different computer calibrations (what you put in when you set it up) and different tires/wheels.
simple mathJay H
Jul 9, 2001 5:48 PM
..and some computers are set to stop keeping time after it senses no wheel spinning while others are set to only start/stop via user input (pushing a button).

The alternative is the guy with the fast time did a wheelie the whole trip and he has a sensor in the front... Then his average speed could be real high yet he'd finish the same time.. :-)
one other thing to keep in mind...Akirasho
Jul 10, 2001 1:29 AM
... computer/calculators... don't add and subtract like we do... that is, they use algorithms... that can produce some interesting quirks.

A few years ago, I was doing a simple (non cycling) average... but it didn't look right... after rechecking by hand... the average indicated by the calculator was indeed wrong... and wrong in every other calculator I tried it in at the time...

This type of error is rare... but they do occur (if I'm lucky, there'll be a few more zeros to the left of the decimal point on next week's check)... depending on the algorithm used in your 'puter... you could get some odd readouts at times...

Be the bike.
re: Cyclecomputer argument!!!yoodoofus
Jul 10, 2001 6:27 AM
Do you really think every computer is calibrated EXACTLY THE SAME??? And all the factors that affect calibration (tire diameter and wear, rider weight, etc.) will be the same for each rider??? If so do you really think every rider takes EXACTLY THE SAME line over the course of a ride??? Geez
re: Cyclecomputer argument!!!guod
Jul 10, 2001 8:05 AM
My opinion is that you are.... well - dumb. No way all 'computers' are calibrated the same. Various tire diameters and air pressure, diffrent lines thru corners, automatic start/stop, etc. I sure hope you haven't lost any sleep over this.
I'm humbled by your superior intellectCRM
Jul 10, 2001 9:34 AM
I really appreciate you taking the time to insult my intelligence in your post. I didn't remember providing my opinion on the question in my original post, so I'm impressed that you deduced that I was "well - dumb." I'm not sure why you waste your superior intelligence on these simple message boards, but in the future perhaps you could simply post an answer without being a jerk.