Component manufacturer SRAM is bringing its single-chainring transmissions to the road with a pair of variants on the Rival and Force groups joining the range it calls 1x.

SRAM introduced its first drivetrains based around a single chainring and massively wide-range sprocket set for mountain bikes in 2013, expanding the idea to cyclo-cross bikes in 2014 with Force CX1.

Now SRAM is aiming at road, gravel, adventure, fitness and triathlon applications with SRAM Force 1 (which replaces CX1) and SRAM Rival 1.

The 1x system (which SRAM wants us to pronounce 'one-by' – good luck with that) comprises three elements. SRAM’s X-Sync single chainrings are now available in a range from 38 to 54 teeth; wide-range 11-speed cassettes are available in 11-36, 11-32, and 11-30, plus the whopping 10-42 introduced for the original mountain bike 1x, which needs a special XD freehub body. Finally, there's the clutch mechanism rear derailleur which controls chain slap.

SRAM says: "Conventional thinking about what’s truly necessary on the bicycle is being scrutinized. Efficiency, lightweight and functionality are the preference over excess, redundancy and complexity."

The company says a 1x transmission can give the same range as a double chainset. A 46-tooth chainring with the 10-42 cassette in fact gives a slightly wider gear range than a 50/34 compact double with an 11-25 cassette. There are definitely some interesting possibilities here for inveterate ger tinkerers.

As well having appeal for general riding and messing about on dirt roads, the system may well suit time trail riders who want to keep things simple. with a 54-tooth chainring, a less outre cassette than the wide-rangers, like an 11-26, yields a gear range from 56 to 133 inches and no need to think about a front derailleur while you're fighting through the lactic acid.

SRAM will offer matching brake levers for its mechanical and hydraulic stoppers, and trigger shifters for flat-bar bikes.

Force 1 and Rival 1 components will become available this summer, starting with brake levers, disc brakes and derailleurs in June, cranksets and chainrings in July and the 11-36 cassette in August. Some cassette sizes are already available as they are part of existing mountain bike and cyclo-cross sets.

Prices are laid out in this Excel spreadsheet. Also: full specs of the new groups and SRAM's complete product booklet For Force 1 and Rival 1.