o0norton0o
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- Joined
- Apr 27, 2015
- Messages
- 1,715
I have a hand held GPS that I have mounted between my tach and speedo, so I use that GPS speed indicator to check my speedometer accuracy and then use "math" and the gearing commander calculator to check my tachometer accuracy too. Ultimately, my clocks are reasonably accurate up to about 55-60 mph, then after that they are a little bit "optimistic", than the GPS numbers indicate. For my needs they are good enough.
At any speed on my GPS, I can remember my instrument readings and check the accuracy for that range, but since I'm just riding for pleasure, not high performance, all I need is reasonable accuracy. I can see where determining exact speeds and rpm's more accurately would be much more important for chosing sprocket sizes for race bikes.
I've measured my tire circumference, and I do manipulate the tire input data in the gearing commander table so the tire circumference column is the actual measured circumference of my tire, rather than the automatically computed one... I'm going to have to revisit my calculations and come back with the comparison of them both for curiousity's sake...
At any speed on my GPS, I can remember my instrument readings and check the accuracy for that range, but since I'm just riding for pleasure, not high performance, all I need is reasonable accuracy. I can see where determining exact speeds and rpm's more accurately would be much more important for chosing sprocket sizes for race bikes.
I've measured my tire circumference, and I do manipulate the tire input data in the gearing commander table so the tire circumference column is the actual measured circumference of my tire, rather than the automatically computed one... I'm going to have to revisit my calculations and come back with the comparison of them both for curiousity's sake...