We've had strong suspicions for nearly two years now that SRAM was developing an electronic road group and now we have confirmation that it's nearing reality. SRAM employee Mike Hemme was recently spotted racing a prototype group at the Illinois state cyclocross championship and while the company won't talk about it, a closer inspection of available images reveals plenty.
Similar but different
The basic elements of SRAM's electronic system look to be similar to those of Shimano's Di2 and Campagnolo's EPS systems. Motorized front and rear derailleurs are powered by a small rechargeable battery and connected with wires – sorry, folks, this one isn't wireless, either – to shift levers that resemble their mechanical cousins.
The premise seems the same, too: By removing the variability over time of conventional steel cables and housing, SRAM's electronic transmission should provide more consistent long-term shift quality and require less maintenance
The levers bear a striking resemblance to SRAM's current Red 22 DoubleTap levers with nearly identically shaped hoods and brake lever blades. In fact, even the shift paddles sport the same parallelogram shape as the mechanical version.
SRAM looks to have adapted its unique DoubleTap shift lever action to button form. Assuming SRAM has indeed carried over the mechanical shifter's unique push-push motion – which would be smart – the electronic levers likely use some sort of two-stage button to select between upshifts and downshifts instead of the separate buttons used by Shimano and Campagnolo.
Again, SRAM has declined to comment on any specifics of the group. "What was seen in the photo is product that's in development," said SRAM road PR manager Michael Zellmann.
The derailleurs are clearly still in the prototype stage at this point but there are still a few details to be gleaned.
The rear derailleur has a bulky motor hanging off of the back end and is more similar in size to Shimano's version than Campagnolo. For the time being, there is no clutch mechanism on the short carbon fiber pulley cage, and given that the system is likely to be aimed primarily at road racers, we don't expect to see one as weight is already bound to be a concern with the added motors and batteries.
Wiring and power
SRAM's system appears to stray from the Shimano Di2 and Campagnolo EPS layouts in a couple of key areas. For one, the SRAM system appears to use two individual wires that run all the way from the front end to the rear. Shimano and Campagnolo, on the other hand, essentially use just one.
It's unclear if the box affixed to the stem on SRAM's system is a battery or electronic 'brain', but our suspicions lean more toward the former with the logic boards then hidden inside the lever bodies. Henne's Cannondale SuperX isn't configured for internal routing and the wires are clearly affixed to the underside of the down tube. Though an internal battery is certainly possible, Henne would have had to connect it individually to each derailleur – a convoluted arrangement that likely wouldn't sit well with mechanics or bike companies that might look to spec the new group on complete bikes. The box on the stem also looks a little big to just be an electronic command unit.
Though both Shimano and Campagnolo are moving toward internal batteries, SRAM's stem-mounted configuration — if that is indeed what it is — may offer some advantages. It's quite small and would be relatively easy to attach to both road and time trial bikes. And from a mechanic's standpoint, the SRAM arrangement is a closer analogue to conventional mechanical drivetrains and looks to be easier to install. You also wouldn't have to fuss around with internal routing aside from running the wires from the shifters back to the derailleurs – just as you normally would, anyway.
Vaporware or a sneak preview of what's to come?
It's no secret at this point that SRAM is off the back in the electronic drivetrain wars, so we have no reason to believe that this is merely a development exercise, especially given the relatively finished look of some of the bits.
Traditionally, SRAM has launched new road groups in very late winter or early spring so we expect to learn more sometime within the next few months. Stay tuned.