Eleven cogs side by side is a sight that road cyclists have long been familiar with: The derailleur specialists at Campagnolo, followed shortly afterwards by Shimano and SRAM, have long since made the switch to eleven sprocket sets for their top components - without reducing the number of chainrings, however. However, SRAM has done just that for mountain bikes: the high-end "XX1" groupset was launched in 2012 with 11 sprockets and just one chainring, and now Shimano also offers a Deore XT version with the technology in addition to the top XTR groupset. SRAM has now also entered the mid-price segment and recently even wants to convince racing cyclists of the new simplicity with a specific "1 x 11" groupset.
The prerequisite for this is an enormous sprocket set on the rear wheel. Instead of the usual 11-34 sprocket teeth, SRAM and Shimano now have up to 42 teeth. These sprocket sets alone cover roughly the gear range of an Alfine eleven-speed hub, but remain well below the gear range of a standard trekking bike transmission with 3 x 9 or 3 x 10 gears.
The increased number of sprockets from ten to eleven allows moderate gear steps despite the large spread. The "fastest" lower gears only differ by two teeth each, with the 3 and 4-tooth jumps only starting from the centre of the sprocket set. A further increase in the number of sprockets is not to be expected for the time being: in view of the current width of the frames, the necessary rear wheel stability has largely been exhausted. Even wider sprocket towers would make a new installation dimension for wider rear wheels sensible.
What could also make the technology sexy for trekking cyclists is its simplicity. There is no need to look at the gear indicator or chain skew when shifting. The gears can simply be shifted one after the other as with a hub gear system. The "1 x 11" is also a visual gain due to the elimination of the front derailleur and the associated shifter and cables. A special tooth shape on the chainring prevents the chain from jumping off on bumpy surfaces. The weight saving with a high-quality Deore XT derailleur combination for mountain bikes is around 350 grams, with simpler material it would be around 500 grams. So far, 1 x 11 gear ratios have been particularly popular in mountain bike racing (cross country and enduro), with the first parts trickling onto the road bike market. We asked industry insiders whether trekking bikers will also be able to travel easily in the future.
The complete article was published in Trekkingbike issue 5/2015. You can read the entire issue in the Trekkingbike app (iTunes and Google Play) or order the issue in the DK shop.
You can download the individual articles as PDF files here.
