Road Cycling - 42 x 21 too big for big hills?

This is the smallest gear I have. Assuming I'm not in a total couch potato, would this be sufficient for most hills? My bike is definitely geared more towards racing, but I use the 42x21 a lot on hills. Doesn't kill me, but the hills aren't that long...

That's not extremely low gear.. my lowest on my one road bike is 39x25, the other is 30x25. It really would depend on the hills and your strength in the hills, lance armstrong could do it no problem, for me personaly I would like a bit lower gearing then 42x21.

I used to always run 53/39 with a 12-21 cassette but when buying new race bike last year I went with a 42 inside ring, as I thought the 42 would be fine as long as there weren't any really steep hills.42 seemed to be fine for racing but now and again on some really steep hills(especially repeats) I needed to drop down a gear and spin it rather than being stuck and having to get out the saddle.

Didnt like using a 23 or 25 cause of the spacing so put on a 39 and its fine for hilly races.I prefer the 39 on my easy days if out on my race bike so if I have any hills I can just spin up them rather than being stuck from not having enough small gears.

Mr. Carl........swapping only your small ring to a 39 and running 39x21 would in effect be almost equivalent to 42x23. If I was looking for that one extra low gear, I would go with the 39 rather than swapping cassettes.

I used to run 52/42 front rings with a 12-21 cassette. I didn't have too many problems unless the hills got very steep. Since I switched to the 53/39 I must admit that it is easier but I also very seldom get into the 39-21 combo.

I do alot of hills and I prefer to have the 39/53 combo with a 25 in the back for emergency purposes. I have only used the 23 most of the time the 21 is perfect. I ride mostly avg 5-7% 4-10 mile hills.

Do you need a lower gear to get up a hill? -NO, but think about it, if you want to train right, you should have a gear low enough to really "spin" a hill without straining..... At least, that's how I train, maybe you are so strong you are already spinning every hill when you want....

hi,
the easier you go on your knees, the longer they will last.