End of an era: Shimano 105 FC-R7000 crankset

The past couple of years, Hyro has enjoyed the substantial technological leap of going 11-speed with hydraulic braking. Majority of said leap came courtesy of parts from Shimano’s 105 R7000 groupset, with exceptions due to identical parts (the 105 FD-5801 front derailleur) or frame design decisions (Post Mount hardpoints require the BR-RS785 brakes and accompanying ST-RS685 STI levers).

I left one upgrade on the table for a very long time, though. I soldiered on with 11-speed everything except for my FC-5750 crank, from the Shimano 105 5700 10-speed groupset. The main reason I had stuck with it for so long was that I had just replaced its worn-out chainrings, and among all the parts of a groupset the crank is usually considered the one with the least compatibility headaches.

Or so I thought.

“Least compatibility headaches” might have been true at the beginning, when the chainrings were still fresh. However, with time and kilometers ridden, I suffered more frequent inside chain drop, especially if I wasn’t mindful enough to shove the chain onto the relevant end of the cassette before shifting at the front. Shimano also said the 105 R7000 crank was designed to better accommodate road bikes with disc brakes, as its stance and chainline are both slightly different from older 105 crank models.

It took the arrival of my 4iiii Precision power meter, itself based on a 105 R7000 left crank arm, to realize that maybe I had been holding back for too long. I was not doing Hyro and my riding any favors by continuing with a compromise, and besides – the crank is by far the visible heart of the entire groupset.

So here we are with Shimano’s 105 FC-R7000 crank, but still in the same spec: 50/34T chainrings, 170 mm arms, and the old reliable 24 mm hollow steel spindle. This is about as plug-and-play as a bike part install gets, especially considering my Shimano BB91-41B bottom bracket bearings from 2015 are still spinning smoothly and without any noise. Who says press-fit bottom brackets all creak? Mine don’t, at all. Kudos to Giant for making a fantastically reliable BB86 bottom bracket shell.

Spinning smoothly since 2015. If your press-fit bottom bracket creaks, blame your frame manufacturer.

That left crank arm is staying in storage, though. I have no reason to run that when I already have the 4iiii power meter crank arm.

724 g all in. 4iiii’s power meter pod adds 9 g.

The underside of the big chainring has its shift ramps scalloped out – a design feature carried over from the previous generation 105 FC-5800 crank, perhaps done in the interest of saving weight. This is about as weight-weenie as I’d get with cranks, and the reason I did not bother with Ultegra or Dura-Ace cranks with their two-piece hollow crank arm construction. While that technique of bonding two pieces into a hollow crank arm is impressive for weight savings, it’s also invited a spate of frankly dangerous crank arm failures.

Nice design, but I dread working on it. Better have some spare shift cable just in case you mess up.

Replacing the crank means re-tuning the front derailleur to suit. This is my least favorite part of working on a modern 11-speed bike, by far. While I appreciate Shimano baking in onboard cable tension adjustment into the cam-action pinch bolt, the instructions the Japanese firm publishes are best followed when you don’t have a chain running through the front derailleur cage. Dialing in cable tension with the 2 mm grub screw and lining up the tension marks can be frustrating with the chain in the way, and doing this enough times can kink and fray your shift cable into an unusable, wasted state (hint: better to put the chain manually on the big ring first if you don’t have a master link). If there is an argument for going the master link route with your 11-speed chains, this would be the biggest IMHO.

(L) 105 FC-R7000, (R) 105 FC-5750

That said, Shimano wasn’t lying about the 105 R7000 crank’s revised stance. At full throw, prior to readjustment and tuning, the front derailleur cage didn’t move outboard enough to shift the chain to the big ring. Limits had to be reset, cage orientation repeated, and even the little support bolt bracing front derailleur against seat tube needed adjustment. Once done, the now-completed 105 R7000 drivetrain is much more tolerant of front shifts at non-ideal rear cog placements. I have yet to suffer a dropped chain – fingers crossed this holds true even after much riding.

With the crank swap goes the final vestige of 105 5700 on Hyro, which was my favorite iteration of Shimano’s workhorse groupset from an aesthetic perspective. While I appreciate the functional and ergonomic improvements in newer groupsets, I haven’t yet warmed up to the brasher, chunkier, more angular cosmetics of 105 R7000, and by extension Dura-Ace R9100 and Ultegra R8000.


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