Earlier this year I picked up a 2014 S-Works Tarmac SL4 Dura-Ace Di2 and since then have spent a lot of time riding it. Let’s start with this, the bike is awesome. I really enjoy riding it. It is ridiculously lightweight weighing in at 14.88 lbs as pictured, it climbs like a rocket ship, and it rides far smoother than I ever imagined it could.
The shifting on the bike is amazing. Amazing. I’ll be honest, I didn’t want to like Shimano Di2 the first time I rode it. I was a fan of Sram (particularly DoubleTap) and didn’t like the idea of a battery to charge and wires. The first time I rode a Di2 bike on a steep hill and threw the front derailleur over to the small chain ring I was sold. It didn’t complain, it didn’t make any angry noises, it just did exactly what I asked, all while being quite and fast.
In addition to the best front shifting I’ve ever experienced, several other Di2 features sold me on it as the group for this bike. I love that the front derailleur trims itself every few rear shifts to ensure no rubbing. I love that I can change the shifting buttons to do whatever I want. This is cool for things like making the left shifter act the same as the right shifter as I have done, but even cooler for people with special handicap needs and want to be able to shift with one hand. Di2 rocks.
The crank on this bike is a thing of beauty!
The brakes are powerful and provide even modulation.
I’m a big fan of the internal cable routing, and internal battery for the Di2 shifting.
The wheels are light, have quick engagement, and the braking is good even in wet conditions.
The bike rides much smoother than I thought it would. I expected a bit of harshness compared to the Specialized Roubaix I previously rode and was pleasantly surprised how similar the compliance was. The geometry is a change from the Roubaix so my riding position has been stretched out a bit now. I still find myself very comfortable after four hours in the saddle. The handling of the bike was the biggest difference compared to the Roubaix. The steering is noticeably quicker. While screaming down hills in Southern Illinois at over 47 mph, steering inputs don’t require a lot of force, I can attest.