I got to ride two different bikes today with the new Dura-Ace R9100. The first bike was the Fuji SL disc. This is a revision of the SL, which was introduced last year. The SL disc adds 75 grams each to the frame and fork to adapt them for disc mounts. The frame (in a 56) went from 700g to 775g and the fork went from 290g to 365g. The complete bike with Dura-Ace weighs in at 16.23 lbs. This bike feature a cable-actuated drivetrain.
I also got to ride a Moots Vamoots with the R9100 with cable-actuated drivetrain and rim calipers.
What was immediately noticeable is that shifting action is a bit lighter on the rear derailleur and noticeably lighter on the front derailleur. Dave Lawrence, who is the road product manager for Shimano said that no feature of the group was allowed to slip backward as an expense of improving something else. For anyone who has closely studied Shimano’s offerings, you may remember that on occasion a feature such as braking power took a hit in the quest to make the group lighter. Lawrence says they were unwilling to revise anything in a way that might cause any existing aspect of performance to suffer.
After riding the dual-pivot caliper, I’m curious about how the direct-mount brakes will perform. The point of direct-mounts is to improve braking power, and I have to admit that I don’t see how braking power can be further increased without sacrificing modulation. I suspect the limitation isn’t one of engineering, but my imagination.
Shimano’s early hydraulic discs were rather grabby. It was difficult, if not impossible, to feather the brakes while riding in a group. Touch a lever and whoever was on your wheel was likely to yelp. The ability to lightly touch the brakes and scrub the tiniest amount of speed has made riding discs in a peloton much easier. Not only is overall brake power as memorable as a Donald Trump quote, modulation is as dynamic as a Led Zeppelin album.
The rim brakes have picked up a bit of mass to give them more power and even better modulation. Honestly, I was surprised that they could wring even more power from a dual-pivot caliper, even as they increased tire clearance. Officially, word is the calipers will accept 28mm tires, but then the existing tires will accept 28s. Depending on the tire/rim combination, it’s safe to say you’ll be able to run a 30mm tire in this brake and should the frame have the clearance necessary, it may be possible to run a 32mm tire.
One neat innovation, which will help show just how creative Shimano’s engineers continue to be is that an inline cable tensioner is no longer required for the front derailleur. There’s a small tensioner in the front derailleur itself.
Lever ergonomics continue to be top-notch. If the Eames brothers were designing cycling components, this is what they’d feel like.
The Di2 versions of the group are still some months out. In terms of OE spec and aftermarket sales, the mechanical groups will come first.