Are you strong enough for a 1×11 drivetrain?


1×11 drivetrains are all the rage. They promise to be simpler, lighter and more hardcore than multi-ring setups.

But is the lowest gear low enough for you?


Let’s talk ratios

Here are the lowest gear ratios for some common setups.

The 2×10 setups provide about a 10 percent easier gear than the 1x11s. That’s a big difference.

Let’s talk wheel size

Mountain Bike Action magazine conducted a brilliant rollout test with various 26- 27.5- and 29-inch tires. Here are the median diameters of each size:

(25.9 for life!)

Based on the MBA diameters, here are gear-inches for two different gear ratios and the three wheel sizes. Lower numbers are easier to pedal.

A 29er with 22×36 has the same final ratio as a 26er with 28×42.

Let’s talk power

Using this handy dandy Excel calculator, you can estimate the wattage required for any body weight, bike weight, slope and speed. This is a dull blade, but it helps us compare setups.

Imagine churning up a long, steep hill in your lowest gear. You’re not in a hurry. You just want to get your carcass to the top so you can Enduro™ the next downhill.

Here are the constants:

Body weight: 180 lbs

Bike weight: 30 pounds

Wheel diameter: 27 inches. I ride 29ers, but 650B is more fashionable.

Uphill grade: 15%. Pretty darn steep.

Cadence: 80 rpm, which is healthy and efficient

According to the Excel spreadsheet, here are the wattage requirements for different gear ratios.

The lower gears let you grind up this hill with about 9-10 percent less power. That might not seem significant, but:

From my training with stationary and Stages on-bike power meters, I know I can sustain 300 watts for 20 minutes. This is on a perfect day — and it requires full effort: neither sustainable, repeatable nor fun.

At 270 watts I can relax: enjoy the ride, work the terrain and keep some gas in the tank. That 10 percent reduction is the difference between red line and sweet spot. The difference between “OMG when is this over?” and “Right on. I’m stoked!”

Give me the gear that lets me stay in the sweet spot. (And take it easy when I’m tired, and warm up gradually when I’m sore.)

Before you switch to 1×11, ask yourself:

Where do I ride? Short, steep climbs can be attacked. Long, steep climbs have to be bargained with. Does the trail turn steep right from the beginning? If so, consider a warmup gear.

How strong am I? If you start riding a 10% harder gear, you might get 10% stronger. But, honestly, is that you? If you’ve been suffering on climbs, a harder gear is not likely to improve your life. On your next ride, don’t use your easiest gear(s). How’d it feel?

What size wheel am I riding? All things being equal, bigger wheels should mean easier gears.

My main trail bikes — a Specialized Camber and Enduro, both 29ers — have 2×10 Shimano drivetrains. They shift perfectly, the chains stay quiet and the low gears are there when I need them.


I rarely use my 22t chainring, but it sure is nice at times like this.

How about you? What are you riding?

Lee

UPDATE JAN. 26, 2015:

Some riders — depending on crank brand and bolt pattern — can use 26t chainrings with their 1x setups.

This gives a 0.62 ratio, which is very close to a 2×10 setup with a 22/36 low gear.

Sweet!


Know more. Have more fun!

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