Getting a FS 29er and can't decide between a 2x10 XTR or a 3x10 XO setup.

Thoughts on which one?

the 2x10 should have enough gears to get you where you wanna go. 3x10 has lots of overlap. it's kinda personal preference. i would go 2x10 because it's simpler. i would also go sram for a drivetrain, shimano for brakes, and that is just personal preference.

XTR and XO both come in a 2X10 and a 3X10, Is you dilemma on 2x10 vs 3x10 or SRAM vs Shimano.

I am SRAM all the way on my MTBs, and when I replace stuff I am going to a double up front, I just don't use 3 the big ring.

I got a 3x10 X9 and ended up wishing I had gone with a 2x10 -- definitely a decision you want to make now rather than later.

What bugs me the most on the 3x10 is not the gear overlap, it's all the chain slap and always worrying about hooking the long derailleur cage on stuff.

It's 2 bikes I'm looking at.

One has SRAM XO 3x10

The other has XTR 2x10

What are the differences between XTR and XO.

This is my first new MTB in 15 years.

Honestly you cant really go wrong either way, both great stuff. I started running SRAM because I used grip shifters due to a hand issue and stuck with it. Even though I a SRAM fan, all being the same on both bikes, I would go with the XTR because of the 2x10. You will be getting a great bike either way. Congrats and post picts!!!

https://gear-calculator.com/

what is the difference between lambourghini and mazzerati? XTR and XO are both top o the line. you win either way.

2X10! I'm running 3x10 XT on my 29er, and I never use my large sprocket. 32/11 will get you going about 35MPH at 100RPM.

As others have said, great either way. I don't really see any need for 3x10 myself. I say base your decision on the rest of the bike and how well it fits you. The model of fork would be an important thing to look at.

Fork is a RockShox Reba RL 29.

Is this a good fork?

Like I said before. My knowledge of current MTB info in non-existent.

I'm a roadie.

I'll agree with the others and say 2x10. The less mess to deal with up front, the better. And the Reba is a great fork--you can't go wrong with a Reba.

XTR 2x10. Sick. Really sick.

2x10. I have it and love it.

1x10 / 1x9 is less mess to deal with. No FD, cable, or shifter. 2x10 vs 3x will not give you any weight advantage and robs you of your granny unless you are running granny, middle, BG. If you're going to simplify, make it purposeful.

Why are you telling me this? My mountain bike is a single speed.

If you ride at high altitude and/or in deep mud, the granny ring might be helpful. Otherwise I favor 2 x 10, although geared rather high for XC racing duty... 32-44 with an 11-32 in back, driving 26" tires.

Doing the math, that would require about a 40-inch tire diameter. 32x11 @ 100rpm on a 29er should get you around 25mph, which frankly would be very frustrating to me... if I bother sprinting for the finish line in an XC race, I'm usually approaching 30mph.

I quoted you as suggesting a 2x10.

First MTB in 15 years. What's your terrain and your fit level? yeah I hardly ever need the big chainring but having a 26 for granny may be too hard for some (it is for me)

? XX exists and seems appropriate in your lamborghini comparison, though I personally wouldn't pay for it above X0.