Roadies don’t think too much about their front chainrings. It’s not like mountain biking, where your ring can impede your ability to ride over stumps and rocks due to clearance issues. And road terrain tends to be pretty consistent; you don’t have to make major shifts in split seconds, like in mountain biking. How many times do roadies get balled up in a technical section and have to put a foot down? Never. How many times do roadies drop a chain? Nearly never.

The reason I’m leading with this road/mountain biking discrepancy is so that the roadies don’t turn green when I start talking about the latest in front transmission system technology, which is for mountain bikes only. Actually, roadies, just stop reading right now. No need to torture yourselves.

If you’re still with me, imagine if I told you that you could have the chain security of a single chainring with the gear range of a double? The latest mountain bike crank technology uses an internal gear system instead of a front derailleur and chainrings to accomplish just that.

SRAM was the first company to bring this technology to market last year, after two years of development. Here’s how their HammerSchmidt system works:

The chainrings are replaced by a two-speed transmission built directly into the crank. There are two gear ratios. Your standard low gear is called one-to-one. As in you turn the pedal once and the chainring goes around once. The second is called overdrive, with a ratio of one to 1.6. So turn the pedal once, and the chainring goes around 1.6 times. All this equates to getting a 24/38 gear range with a single ring. Or if you prefer, there is also a 22/36 version.

Shifting happens with triggers on your handlebars that look just like the SRAM X.0 and X.9, except that they’re propriety to the HammerSchmidt system. The triggers pull cable to downshift, and release cable to shift into overdrive, rendering the front derailleur, and its pesky adjustments obsolete.

Imagine the possibilities with this new system. Your chainrings are gone, so you’ve got that much more clearance for riding over obstacles. My personal favorite is that the system doesn’t depend on pedaling to shift. You can shift while coasting, shift on the fly, shift while under a full load, heck, shift in mid-jump just because you can. This particularly comes in handy when you run into a technical climb right before a descent. And consider that the shift, no longer dependent on moving the pedals, will now happen instantly. That’s a level of precision that mountain bikers have never had before.

You’ll never drop a chain again. The single system, along with a chain guard, ensures that it’s literally impossible. Rear shifting gets better too because you’ve got a constant chain line from the rear cassette right into the transmission unit at the crank, improving performance and rear shifting precision. The fact that you’re using a short cage rear derailleur and running a very short chain also helps in this area. Plus, you can use all the gears on your cassette, as it’s now impossible to cross chain. And not that you’re a newbie, but the “rookie tattoo” that comes from rubbing your inner right leg against your greasy front chainrings is eliminated.

Maintenance is simplified, as there are less exposed parts, and cleaning and changing a chain is just as simple as with the “old” technology. Early adopters mentioned the fact that front shifting is reversed with this system was a bit confusing at first. You’ll also need a proprietary bottom bracket and ISCG 03 or ISCG 05 tabs. ISCG adaptors will not work, which means many top end bikes aren’t ready for this new technology, although SRAM assures us they are working with them to incorporate ISCG table on their frames so they are HammerSchmidt ready. The biggest con we can tell is weight. The HammerSchmidt all mountain system is 172 grams heavier than SRAM’s standard set up, the Stylo. The HammerSchmidt free ride system is 11 grams heavier than the standard, the Holzfeller.

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