thehammerdog

I was reading the new dirtrag and saw that almost every bike was a single up front times 10 in back?
What memo did I miss and why is this the rage?
I have an old school 3x9.......so help a brotha out.
The idea of a single front chainring is cools I guess but whats the magic tooth number needed?

I would like some insight as to when this too place.....

mrgrunt99

I believe most 2x10 setups have a 39t outer chainring. I imagine if you did a 1x10 setup with a 32t front chainring, and a standard MTB 10 speed cassete you would a good gear range. The magic tooth number is whatever you will be comfortable with on steep climbs and adrenaline inducing downies!

Daspydyr 

The terrain and the strength of the rider is what determines what you really need for rings. I still like the variety my 3X9 offers. A 2X9 can give you a wide spread and can probably stretch as far as a 3X9. A tad less weight and less shifting would be my guess for the 2X9. Since I ride pavement to get to my trails, I like the 3X9 setup. A 1X9 can save you TAD X's 2 if you get the range that you like.

YamiRider1316

for me 32t with an 11-36

Underground

I'm debating on swapping my HiFi to a 2x10 setup. Possibly a 38/24.

xlDooM

I ride 32t up front with 11-34 9spd cassette but it's a 29er with tall tires. Just keep an eye on the highest and lowest gear you use regularly on your current setup, then muck about in a gear calculator to find the best matching setup for that range.

ColinL

I have a 26" bike with 2x10- 28/39 rings and 11-36 cassette. In Kansas, I can actually ride most trails entirely in the big ring. But I would hate a 32T single because I run out of gear pretty quickly on any sustained downhill section, which is especially annoying if you're out with buddies on a gravel road ride. (I can bring my CX bike instead, but it beats me up on washboard roads.) 28x36 is more than adequate even on the steepest stuff I can do-- I'm no trials rider, so it's better for me to walk when it gets ultra slow and techy.

If you have a 29er I would suggest using no bigger than 38T. I would also caution you to be sure your rear derailleur has enough capacity to use a 11-36 or 12-36 cassette with the 2x10 crankset you choose. That's how I ended up with a 28T small ring-- my SRAM x9 type 2 midcage can't handle the 11-36 cassette otherwise.

born2bahick

I dropped the 39 tooth off the cranks and just run the 26 tooth in a 1X10. ditching the fr derailuer, shifter,cable and housing lost almost a pound off the bike. plenty of gearing for my trails. gravel rides leave me spinning my ass off though.

ColinL

My bike weighs 24.5 pounds ready to ride. So, I'm pretty happy about being able to pedal faster than 13 mph.