Gear-inches = Chainring T / Cog T * Wheel Diameter
I aasumed Wheel Diameter to be 19.5". That's what I have, corresponding to a 42mm wide (nominal) tire.
Originally Posted by
CanadaWriter
Yeah well this is why I'm trying not to eat so many cookies these days. At least I can cut out some fat! Otherwise I'm looking to be biking at 80kg and carrying about 10kg of stuff. The last time I did this I was 83kg and carried 7kg so it was the same difference -- that was on a Speed D8 though. But again, I can't see the difference in the two bikes.
But first thing is first: how did you do the math to come up with 29-84 based on the numbers I gave you?