What is the best Cross Country mountain bike drivetrain set up, 1 chain ring, 2 chain rings or 3 chain rings in the front?
Whether your new or a seasoned pro to the sport of cross country mountain bicycling, you might be contemplating either a new bicycle purchase, or upgrading your existing XC MTB bike’s drive train to one of the many combinations now available for Cross Country MTB riders and XC mountain bike racers.
The choices to contemplate are 1x (1 front chain ring) vs. 2x (2 front chain rings) vs. a 3x (3 front chain rings), with either a 10 or 11 speed cassette on the rear mountain bike wheel hub.
Should I run a 10 speed or 11 speed rear XC mountain bicycle cassette?
If you are considering going with a 1x cross country race setup, that is one chain ring in the front, an 11 speed cassette in the rear is the smartest choice to ensure you have the widest gear range possible for both mountain bike climbing and descending.
1x (1 front Shimano or SRAM mountain bike chain ring on your crankset) conversion / parts upgrade list:
- 11 speed rear cassette
- 11 speed chain
- 11 speed rear dereailleur
- 11 speed rear compatible wheel hub
- 11 speed 1x crankset
- 11 speed rear derailleur shifter (mechanical or electronic)
- Chain guide (optional for extra protection)
Important – Verify whether or not your mountain bike’s rear wheel’s hub accepts the larger 11 speed cassette. This can easily be confirmed by checking the manufacture’s data or talking with a savvy, bike store mechanic.
If your rear mountain bike wheel hub does not accept an 11 speed cassette here are your options for your upgrade:
- Change out your rear hub
- Purchase a new XC MTB rear wheel with the correct hub installed, or possibly this is the time to upgrade your whole wheelset
What are the advantage of the 1x cross country set up?:
- Shave weight perhaps half to three quarters of a pound (225-340 grams) plus additional savings from the crankset upgrade maybe another 100-225grams. This solution does not require a mountain bike Shimano or SRAM front derailleur, front shifter and shifter cable.
- Avoid dropping your chain when it counts (personally I have lost mine in races, and it sucks). No chain, chance of winning are slim.
- Less maintenance (no front shifter, derailleur / cable is music to my ears)
What are the disadvantages of the 1x cross country set up?:
- Upgrade expenses / conversion costs
- Less gearing options which might require an athlete in more peak condition
- Limited lower end parts options to offset costs
Should I run a 2x XC mountain bike drive train race set up?
If you currently have a 3x set up, you could remove 1 chain ring, and go with a 2x setup. The only reason I can see for this type of reconfiguration is if you are experiencing chain drop all the time, and decide to run a Cross Country mountain bike bash guard and XC MTB chain guide.
You are not going to shave any weight. In fact you will most likely gain some weight. If you can get your gearing right for you with this combination, there is great security and confidence inspired with this type of set by assuring your chain doesn’t fall off when you are counting on it the most. Plus your chain coming off will cause frame and other damage, not to mention to the chain itself.
Should I run a XC 3x mountain bicycle drive train?:
Most likely this is what your bike was built with. Most riders aren’t switching for a 1x or even a 2x setup back to a 3x. I say most because GT a few years back tried to defend its stock install of the 3x setup on many of it bikes by claiming it had a lot of riders demanding this type of setup for their trails. Of course the next year they went to both 2x and 1x setups.
So you need to determine if you feel comfortable with this option on your recreational and race trails, then analyze how often your chain is dropping, as this is a deal killer in a race. I personally always liked having the big ring in the 40’s and the super small climbing ring. However the new 1x and 2x combinations are pretty close with an 11 speed rear cassette on the 1x and a 10 speed cassette for the 2x setup.
I ran the 2x setup for many years when it was a new thing on my FR / Enduro mountain bikes, and found it was always a little harder to climb but very doable, and some of that was simply the weight of trucking a 180mm suspension mountain bike uphill, but I always missed the bigger ring when really hitting it hard on the down.
I am a big fan of the 1x race setup if you have the budget. It is simple clean, and truly the wave of the future. While it isn’t on my mandatory list of upgrades for recreational riders, it is very rewarding on both weight and maintenance.
Absolutely a must for racers with trails that work well in conjunction with the 1x mountain bicycle gearing setup. You’ll never look back…