This week, Shimano filed patents for a Dura-Ace 12 speed group with wireless, electronic shifting. A patent filing generally suggests an upcoming product release for Shimano (although not always!) Such a group would compete head-to-head with SRAM's eTap AXS wireless groups (current Dura-Ace offers an electronic shifting Di2 option, but it's wired, not wireless.)
Such a group is ideal for competitive cyclocross and gravel riding. Since my preference is for the shape of Shimano's lever hoods and their hydraulic brakes, my next bike will likely have a Shimano, wireless, electronic shifting group upon release - here's why.
Wireless shifting is ready for cyclocross
- The technology is already proven and mature. Mathieu van der Poel won the cyclocross World Championship on a Dura-Ace Di2 (wired) setup, way back in 2015.
- Shimano products tend to be more "fully-baked" than some competitors. Although SRAM beat them to the market with their 12 speed, eTAP AXS group, Shimano groups tend to be more refined upon release - although that release can lag years behind. When it's finally ready, though, it's incredible. The patent application, for example, hints at "self-charging" shifters that generate their own electricity through the clicking mechanism - clever.
- Smooth, reliable shifting - especially the front derailleur. Shifting back and forth between large and small chainrings is the most difficult shift to make on a mechanical drivetrain, requiring the most hand and finger force. It can be even worse when the drivetrain is muddy or wet and your fingers are frozen by cold. With electronic shifting, however, this challenging shift of the front derailleur becomes effortless and consistent, thanks to the extra force offered by a small motor.
- Secondary shifter locations. Unlike a mechanical drivetrain, electronic can have multiple shifter button locations, for example, the bar tops on a cyclocross bike.
In addition to the on-bike performance, I also love the ease of cleaning electronic shifting bike. There are no mechanical cables to worry about contaminating with grit or moisture, and it's just easier to clean and shine up a Di2 or AXS bike to get it ready to race without cable stops and braze-ons in the way.
Downsides of wireless shifting
Electronic shifting, especially wireless, is not without downsides. You must, of course, charge the batteries that power the system periodically. SRAM says their wireless eTAP AXS setup can go about 60 hours of riding between charges, while Shimano's current, wired Di2 systems get even more - about 1500 miles on a charge. It's too early to tell, but we might expect a future wireless Shimano system to perform similarly to AXS - offering weeks between required charging.
A mechanical shifting system has a bunch of moving parts, but it isn't software. Introducing programming and software via electronic shifting adds complexity and is another possible failure point. The converse, of course, is that manufacturers can continue adding software updates and enhancements over the life of the product, while a mechanical group's features are "frozen" on the day you install it. On a software-based system, the rider can personalize the button orientation and functions as their needs or wants change.
Some bikes are better with mechanical shifting
There will always be a place for mechanical groups even as electronic shifting progresses to wireless. Backpacking and multi-day touring bikes, for example, are probably better suited to stay with mechanical shifting. You wouldn't want to carry a charger or diagnostic kit on tour, and mechanical shifting could be easier to fix in a remote location in case something goes wrong.
Wireless, electronic shifting is going to remain more expensive
Although prices have come down, electronic groups remain more expensive than their mechanical counterparts. You might need new wheels, too - a Dura-Ace 12 speed upgrade is likely to require Shimano's new Microspline freehub body and would not work with the classic freehub design you probably already have. So you may need entirely new wheels; or a freehub swap if the wheels you own already have that option.
As someone who likes to tinker, the idea of tweaking and adjusting my drivetrain features from a computer or mobile phone is intriguing. You're already keeping your cell phone, headphones, etc. charged and plugged in, so what's one more device?
The cyclocross bike of the future has wireless shifting, hydraulic disc brakes, hidden, internal batteries - and I'm fine with that!