Mountain Bike Reviews Forum banner
1 - 7 of 7 Posts

·
Registered
Joined
·
22 Posts
Discussion Starter · #1 ·
I have (I think) a Raceface Next R Carbon crank pictured below.

1943415


I was looking at how to remove it. The drive-side crank arm has a large 16mm and a smaller 8? mm socket.

1943416


The 16mm socket is skinny and soft -- is really easy to round-out if I'm not careful with the driver.

Before trying to really torque this free, I decided to check the official documentation. I think this is the correct reference guide to the crank. But it says absolutely nothing about that outer 16mm bit, just says to tighten the inner bit to 50nm.
1943417


So what's the deal? Am I looking at the wrong docs? Do I really ignore that 16mm bit on the outside? And if so, why does it even exist and mimic being a fastener?
 

·
All fat, all the time.
Joined
·
11,120 Posts
8mm takes the crank off. 16mm is the self-extracting bolt cap, which is a left-hand thread - if you try to turn this CCW, you're just going to tighten it even more. As you back the 8mm out, it pushes against the inside of the 16mm cap, which is what separates that crank arm from the spindle.
Yep this.

Make sure to loosen the preload adjuster on the other side if it has one. Then loosen the 8mm.
Don't touch the big one.

Sent from my SM-G991U using Tapatalk
 

·
Elitest thrill junkie
Joined
·
40,988 Posts
The cranks are a taper-fit, so it often takes a breaker-bar on that 8mm and possibly taking pedals off and using PVC pipe extensions. I would highly suggest not to use an allen wrench, a breaker bar imparts a lot more direct force and doesn't round the interface nearly as easily. IME, when these are properly tightened, they are a little difficult to get off. It's usually worse IME to have a taper-fit a little on the loose side.
 
  • Like
Reactions: dysfunction
1 - 7 of 7 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top