Loving all the advice, guys! I think I understand enough of this, then, to do what I'm doing right now. I think it's just me, but I find Sheldon really hard to follow. I'm a teacher, and we talk all the time about something called "background knowledge," and the assumption that your reader already knows certain things and can therefore follow your references. I feel like Sheldon's making some assumptions about stuff that I don't already know. I read through his page on shifting and felt just as stupid at the end as I did before I read it. Oddly, you guys don't make me feel that way. I know everyone else loves Sheldon, so it's really probably just me .

The 3-speed was actually helpful for learning all this. It's so simple, but with a SA hub, the lower gear is really high, so boy... you shift, or you die. And the highest gear is so freakishly beautiful for straight patches that I use it a lot too. I shift more on the 3-speed than any other bike I've ever owned. But I think it's helped me to understand when to shift up and down, because I'm not trying to work with 21 gears or 14 or even 10. Just 3! I've been working with my boyfriend's daughter, who is nine and riding her first bike with gears, on shifting down. Her dad has told her that if she stays in the higher gear, she'll get a better work out. Needless to say, he doesn't really ride much. So the other day, we're riding up this really tough short hill, and I see she's stopped and is walking her bike up the hill. Yet I'm on the 3-speed Sports, and I'm riding up it. What's up? Well, she's still in like... 20th gear. So we had to have a chat about shifting down. It's odd how explaining something to someone else helps you understand it yourself.

But reading all these posts helps too because a: I feel less stupid (there's not some magic thing I'm not getting) and b: I know about cadence now, and it makes perfect sense to me. If I can expend roughly the same amount of energy over a longer ride, I can increase my endurance. The part about trimming the deraileurs was amazing too, as I had sort of figured that out through trial and error, but thought it was just me being a newb and ruining my bike. Now I know it's a skill. So cool! Thanks!

I still don't get the indexed vs. friction thing. How can a gear be incrementally on or off? Isn't it either on the cog, or not on the cog? So when would one want to switch to a friction set up? Mine is currently on indexed. But I can switch, at least the smaller cogs. Why would I do that? When would it be useful?

And let's say that I'm riding along in the lowest gear (little big cog, big little cog), but I want to quickly go to a middle gear (big big cog, big little cog) to pick up speed before a hill, then shift back down rapidly to go up the hill. I assume I don't have to shift through all the intermediate gears, yet when I tried just switching the left hand lever, it made a lot of noise and scared me, so I stopped. What's the scoop on a situation like that?