new ss

Depending on terrain , I might look at 17 and 18 tooth cogs . I prefer wide base cogs . If you can wait a bit , I.S.A.R. cogs are the shiznit , he's on the board here . Surley cogs also have alot of fans .

I would suggest getting a 20t to try in addition to the 18t. Gearing is different for 29ers, and for average trails many people end up with something in the 32x18t to 32x20t range. 32x17t is kinda steep for most trails, but for flatter trails it might be appropriate. On the other end of the spectrum, for climbing in the multiple thousands of feet many people use 32x21t or 32x22t.

As for brands, Surly is the best option for an affordable and durable cog with a wide base

thanks guys. i tried to do a search but when you type cogs into the search box it doesnt do much help.

Where do U ride?? and is there alot of climbing? or flats? this will help determine the cog size. I ride an 07 Rig 32x21 I live in Western Colo. and like this for the climbing! Been riding SS for 5yrs and like the Rig. Good luck!!

i am in northern illinois so a lot of flats but some of the stuff has a lot of ups and downs.

On REALLY flat stuff I'll run a 33/16. For more ups and downs 33/18 works for me. If it's a really brutal course 33/20 may be an option. Spinning a 33/20 on the flats wears me out so the track has to be very steep to go that route. Often it's faster to hop off your bike and jog up the hill than grind up it at 2 mph. By the way, I ride/race in Virginia on a Ferrous 29er. Also, I use the cheap stamped cogs but will be switching to Surly's or something similar very soon. The stamped ones chew up the freehub (even the steel kind).