I'm trying to understand gearing and cadence and so on in an effort to not mess up my knees and to gradually improve my aerobic conditioning. Oh yeah, and then there's weight loss ...
This is what I have figured out so far:
I finally got around to putting my bike specs into the rpm calculator on sheldon brown's website. (I don't have a cadence meter but I have gotten pretty good and squinting at my tiny printout and eyeballing my gears to figure out what my cadence is.)
Assuming a fairly constant speed and level terrain (hurrah for canal-side paths!) I can poke along at 70rpm for miles, can sort of maintain 80 if I think about it, and can inch up to 100 for a short while (I have plain old pedals). Then I start huffing and puffing like an out of shape middleaged woman. Uh, wait ...
So I know that I want to increase my aerobic capacity and get a higher rpm.
If I want to go, say, around 16 or 17mph between 80 and 100rpm, then I have several choices of gear combos
(Uh - the bike - 2007 trek 7.2 w/ 48/38/28 + 8 speed 11-32)
80rmp: 28+11 or 48+18 or 38+14
90rpm: 48+21 or 28+12 38+16
100rpm: 28+14 or 38+18
I'm trying to understand how the different combinations of gearing yield a different feel to the pedaling - some combos are easier then others and I don't think it is just the different RPMs. (remember, speed and terrain are fairly constant) I have, so far, tended to stick to the 28 or maybe 38 and rarely venture onto the 48. It seems to me that 90rpm in 48+21 is tougher then 28+12.
Anyone care to explain this to me? Or am I nuts? Or overthinking (again)?
Hope the no-doubt non-standard nomenclature is not too confusing.