“It’s like riding rodeo”, blurts out Greg Herbold. “I can now grip with my left, and hold onto the bucking bronco while I sort out my controls with the right”. He breaks into a little demonstration of bull riding style while the assembled hacks chuckle.
He has a point though. XX1 makes things simpler so you can just ride harder, whether you’re taming a beast of a trail or galloping on singletrack.
This new drivetrain isn’t more complicated. Yes, it has more gears on the cassette but it’s tidied up and simplified a lot of the rest of the drivetrain. And even though there is added weight in certain places (we’re talking mere grams here and there) the overall drivetrain on the XX1 is 200g lighter than XX. It could also make drivetrains stronger and more resilient to wear. Why? Well, with the chain line stresses are reduced (no more cross gearing now), the chain is made stronger because it doesn’t need to shift up huge chain ring gaps, and with the single chain ring designed only to hold the chain and not intentionally drop it for shifting, parts can be stronger and less prone to wear.
The last thing might surprise the naysayers who bemoan more cassette cogs and who wish for a return to the halcyon days of nine, eight, seven or six speed cassettes, but it’s true. You see, XX1 isn’t about introducing more gears and adding complexity, it’s about remedying some of the issues that drivetrains have had since, well, forever.
No longer does the drivetrain have to be designed to deliberately derail the chain in order to get more gears. Look at a drivetrain in motion; the bottom portion of the chain is under very little tension, hence why it slaps about making a racket and eating your bike alive. Meanwhile the top portion is under a huge amount of stress and torque as power is pulled from the crank arms through to the rear wheel. To then derail the drivetrain while under such tension is difficult to engineer and comes with hazards and issues. But that’s what we’ve been doing with triple and double chain rings for years. We’ve had a mechanism which derails the chain, and then chain rings that can lose the chain and help move the chain to shift between gears.
Now instead, the chain rings actually grab the chain and really try not to let go. The tooth profile on the chain ring is deep and pronounced. There are also hooks on the inboard side and cross-headed teeth. All of this is designed to hold the chain onto the single front ring at all times, without the need for a chain guide.
To test this SRAM kindly took us to the Top Of The World, the new trail that leads from Whistler’s peak and snakes nearly 5,000ft to the village. The trail is rough, dry, rocky and, at times, fast. Like, face-meltingly, eye-bleedingly, scarily fast. We followed the same route that the Crankworx Canadian Open Enduro raced down the weekend prior which included a large portion of Whistler’s Garbanzo and Fitzsimmons Bike Park trails. This is the kind of place that’s a downhill bike-only affair. That we were on 27lb highly pedalable XCish machines and wearing no pads and half-lids didn’t seem to phase anyone. Nor did it phase the poor bike’s drivetrain which not once even hinted at a dropped chain.
Only once we got down safe and had a cold drink in hand did the realisation about what SRAM have achieved really hit us. They’ve managed to make a system that is lighter, stronger, and solves some of the most prevalent problems with mountain bikes. We can now have less clutter on our bike’s handlebars, at the bottom bracket and on the frame. We don’t need a front shifter, nor front mech, nor chain guide. This isn’t a small development, this is a radical new direction of thinking that will benefit riders and engineers. Riders, because they can have much more for less, and engineers because now they don’t have to engineer around the front mech while designing frames that more and more these days have less and less space at the BB junction. Suspension design pivot location can be harmonised too. And this all benefits us, the riders.
After the Top Of The World ride I stole the test bike and have absconded for a few weeks with it for some more demanding evaluation on trails with more climbing and as much descending. Keep an eye out for the full XX1 review in the December issue of Spoke Magazine.
There’s heaps more info we have posted up here on XX1 if you’re keen for a read.
Caleb also fired me through a few questions that Spoke readers have asked regarding XX1.
Is it possible to run the new XX1 chain rings and chain with a 2012 style SRAM 10 speed cassette? i.e for people to upgrade slowly.
You will need to upgrade all parts to 11 speed. The chain is very specific and chain management will only work with all 11 speed parts and chain.
Can you run the current cranks and just buy the spider and chain rings?
You can use an X0 crankset but for the correct Q factor (the Q factor is the distance between crank arms at the pedal) XX1 crank is better and it all is matching.
I bumped into Easton’s MTB marketing manager Dain Zaffke and asked him if Easton had any plans to make a XX1 compatible freehub?
No. No plans for that right now.