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pharoahsanders
SCS
One question...why the discrepancies in various peoples GI calculations? I know it changes with tyre/wheel size etc., but for the example of 49x15, if we assume 700c wheels and 23mm tyres, I get 85.93 on every calculator I try...I have to put down 32mm tyres to get close - don't really see them on track! In another example, 50x15 is oft quoted as 90 inches, while I always get 87.68.
Anyhow, I haven't changed sprocket or chainring in months (47x14, 88.3GI by my reckoning!) so I guess it doesn't matter!