Originally Posted by samal
I am running a 42x16 on my bike right now. It's a bit easy for me, so I am thinking about going a little bigger. My question is, should I change the chainring or the cog? should I go 42x14, 44x16 (it seems to me that they should be the same) or 46x16? Is there a benefit to changing the cog over the chainring (or vice versa)?
thanks
42x14 and 44x16 are not the same. changing one tooth in the rear gives a bigger difference than changing one in the front. it's roughly a 3-to-1 ratio. three teeth in the front are equivalent to one in the rear.
anyway,
http://sheldonbrown.com/gears/ will offer some insight on how much you're changing. i used to ride 39x14, which was 73 gear-inches, and chanced to 46x16, which is 75 gear inches. i was surprised at how noticeable the difference was. make smaller changes. i'd go for 44x16 or 45x16 under the circumstances. if you're not picky about your products, you can find cheap chainrings. rocketrings come in both 110 and 130 bcd (bolt circle diameter-- the important measurement for chainrings) and are eighteen bucks. and if you ask your local bike shop, they might have used/discarded chainrings lying around in the shop that they'd give you for free or cheap.