With SRAM launching the first 12-speed mountain bike groupset, how long will it be until we see another sprocket on road bikes?
If you’re more at home on the tarmac than the trail, then you might not have taken much interest in the launch of SRAM’s new mountain bike groupset. But for 2017, the American company has added a 12th sprocket to its XX1 and X01 groupsets, which got us thinking, could we soon see 12-speed road groupsets?
In mountain biking, the jump from 11-speed to 12-speed has been very quick with SRAM being the first to bring 11-speed to market with its XX1 groupset in 2012. Contrast this with road groupsets, which were first taken up to 11-speed by Campagnolo in 2008. Indeed, Campagnolo has released three versions of its top-end Super Record groupset since then, none of which have been 12-speed, while the new Shimano Dura-Ace which we expect to be released at some point this year looks like it will also stick with 11 sprockets.
So with two of the big three sticking steadfastly with 11-speed, and SRAM already possessing the technology to produce 12-speed cassettes and derailleurs, it will be the American company that will be at the forefront of road groupset development.
SRAM has a history of taking mountain bike technology and moving it across to its road groupsets, most recently with its 1x single chainring groupsets. This was originally rolled out into its mid-range Force and Rival groupsets, but has since been added to the entry-level Apex groupset. Surely the trend is only going to continue to the top of the SRAM road range with a 1x Red groupset.
If SRAM is committed to pursuing single chainring groupsets on road bikes, then having a 12-speed cassette makes complete sense.
One of the problems we’ve found with SRAM 1x is that if you want to have the range of gearing that will allow you to tackle steep climbs and fast descents, then you will usually be left with big gaps between gears, meaning that you can struggle to find the perfect gear to maintain a comfortable cadence. Having a 12-speed cassette will certainly go some way to solving this problem, reducing the jumps between gears without reducing the gearing range.
Watch: buyer’s guide to road bike groupsets
Before today, this was pure speculation, but now that we know that SRAM possesses the technology to bring 12-speed 1x groupsets, it can’t be long before we see the extra sprocket making its way across to road bikes. Unfortunately SRAM was unable to provide comment when we got in contact.
But what of Shimano and Campagnolo? Surely companies that have been making road bike components for 95 and 86 years respectively would be looking to the future and developing 12-speed groupsets?
Shimano has told us that it has explored the possibility of producing a 12-speed groupset. In fact, the Japanese company told us in January that it had tested 12-speed gears and that production was possible, but wasn’t planning on releasing anything until it had complete confidence in the system.
We’ve contacted Campagnolo to ask whether it is working on a 12-speed groupset but have yet to receive a reply. The Italian company has just released a new mid-range Potenza groupset (which was 11-speed), but has also taken pride at being ahead of the curve with road component innovation, so we’re sure it must have something up its sleeve.
Do we need 12-speed gears?
Over the past three decades the number of sprockets on a bicycle cassette has grown from six, to seven, to eight, nine, 10 and now 11. So will we have 12-speed gears any time soon?
The advantages of having more cogs in your cassette are relatively obvious: you can have a wider-ranging selection of gears, meaning less shifting on the front chainrings, and you can have less of a jump between the gears on the cassette to ensure a smooth pedalling cadence as the terrain changes.
Already, the introduction of 11-speed cassettes has all but killed off the need for triple chainsets, which were introduced to provide lower gears. Now it is common to find cassettes fitted on road bikes that go as low as 32-teeth, coupled with a 34-tooth inner chainring. And you can still have a 50t chainring and 11t highest gear at the back for those fast descents.
Pros and cons
The disadvantages of increasing cassette size are perhaps slightly less obvious. Despite manufacturers reducing the physical width of the sprockets on the cassette, the gaps between them and the width of the chain, the width of the cassette has slowly crept up.
However, the distance between the dropouts on frames has not changed. The only way to accommodate the larger cassette is to ‘dish’ the rear wheel, so that the spokes on the drive side are shorter from the hub to the rim. This has certain strength implications; as you may remember from your school physics lessons the strongest shape is an isosceles triangle with equal angles at its base. Rim manufacturers have experimented with ways around this — some using offset spoke holes to reduce the effect of dishing.
Having less of a gap between sprockets is a double-edged sword when it comes to shifting performance. Less of a gap means less leverage needed to ship the chain from one cog to another. But that also means that there is less tolerance to misaligned derailleurs, sticky cables and worn chains. Of course, this isn’t an issue with the new breed of electronic gears that auto-adjust themselves.
Another drawback is that it’s tricky to upgrade. You cannot simply slap an 11-speed cassette on a 10-speed bike, and the same would be true of 11 to 12-speed. A new shifter and swap to a narrower, compatible chain and chainrings to achieve an efficient drivetrain.
One on the back, one off the front?
Weight is also an issue — more sprockets means more metal. This weight gain has been largely negated over the years with the use of lighter materials, and careful drilling and machining of parts to lose mass, but in some instances this has had a negative effect on longevity.
Bikes with two or more chainrings will have a crossover of gears: the lower selection of gears when in the large chainring is equivalent to the higher selection of gears in the small chainring. This is to give you a wide spread of gears no matter which chainring you are in.
SRAM has just introduced a 1×11 groupset designed for road bikes, having previously introduced them for the mountain bike and cyclo-cross markets. This single-ring set-up at the front has weight and mechanical benefits, both in terms of the missing ring and also the missing gear shifter and cable, although it can never replace the full range of gears in a double-ring set-up. Maybe this is where the appeal of a 12-speed cassette really comes in.
None of the big drivetrain manufacturers has a 12-speed system ready to go, as there are still gains to be made in honing the performance of current 11-speed set-ups and in further development of electronic gears. However, the prospect of ditching mechanically inefficient front chainring shifts in favour of a lightweight, wide-ranging 1×12 set-up is an enticing prospect for some applications.
For: Alex Dowsett, pro rider, Movistar
“12-speed would be welcome for a rider like me [heavy] in the mountain stages of a tour. Traditionally, I’ve had to sacrifice the 53 for a compact 52 or the 11 for a 29 to get the low end of the gearing range. I think manufacturers need to focus on making 11-speed 100 per cent reliable before they think about 12-speed — we’ve seen a few race-deciding mechanical issues this year. In short, I’m all for a bigger range of gears if reliability and weight isn’t compromised.”
Against: Joshua Riddle, Campagnolo
“With 22 gears to choose from, the metric development covered between the two chainrings is quite complete and with the ease of change between standard, semi-compact and compact chainrings, it should be quite easy for athletes to find the perfect gearing for nearly any course. Many factors come into play when speaking about adding more gears and perhaps with the ever-changing standards we see, rear-end spacing could allow such gearing in the future. Only time will tell.”
This article originally appeared in the April 30 issue of Cycling Weekly