That’s two parts. 15mm Allen key for the first part and an 8mm Allen key for the bolt. Sometimes they’re referred to as hex keys.
Edit. The caps not actually a hex… Maybe try a smaller hex pushed in with a rag… Otherwise I suspect you’ll need the manufacturers specific tool.
Wineandbikes on
Ignore the outer fitting. It looks like a self-extracting crank.
8mm hex is usually the one. 54nm is VERY tight, so some force will be needed to remove it. I use a scaffolding ‘extender’ with the bike on the ground. Regular thread.
tca_audioworks on
Thanks! I’ve had some issues with creaking so I suspected one of the bolts is not tight enough. Secured the 8mm one to 54nm with a torque wrench, lets see if that fixes it..
carverboy on
The outer cap provides the inner bolt something to press against so that the crank arm will come off. Without it getting the crank arm off would be difficult.
TJhambone09 on
> Talking about the cap, the large one. It’s not a hex, tried that and didn’t fit..
The outer, “the large one”, as you said is not a hex. [It’s a 15mm oct drive](https://i.imgur.com/ik7i4QW.jpeg) AKA “double square drive” AKA “hex shank”. You can see that the corners are rounded out to take a scalloped drive bit.
But, as others have said, one should never need to tighten or loosen it once installed. It serves as the backer for the bolt in the middle to press against when removing the crank, the so called “self extracting bolt”.
BD59 on
It says right on the cap…15mm for the big one, 8 mm for the small.
Open your eyes, man
Greedy_Pomegranate14 on
To remove the cranks, you leave the outer cap in place and turn the inner bolt with a 8mm hex wrench counterclockwise. The inner bolt will push against the outer cap and pull the crank off the spindle. That’s how “self extracting cranks” work.
To remove just the outer cap, you need a 15mm hex wrench. It says so right there. Some of those outer caps are reverse threaded, not sure if Rotor is or not.
7 Comments
That’s two parts. 15mm Allen key for the first part and an 8mm Allen key for the bolt. Sometimes they’re referred to as hex keys.
Edit. The caps not actually a hex… Maybe try a smaller hex pushed in with a rag… Otherwise I suspect you’ll need the manufacturers specific tool.
Ignore the outer fitting. It looks like a self-extracting crank.
8mm hex is usually the one. 54nm is VERY tight, so some force will be needed to remove it. I use a scaffolding ‘extender’ with the bike on the ground. Regular thread.
Thanks! I’ve had some issues with creaking so I suspected one of the bolts is not tight enough. Secured the 8mm one to 54nm with a torque wrench, lets see if that fixes it..
The outer cap provides the inner bolt something to press against so that the crank arm will come off. Without it getting the crank arm off would be difficult.
> Talking about the cap, the large one. It’s not a hex, tried that and didn’t fit..
The outer, “the large one”, as you said is not a hex. [It’s a 15mm oct drive](https://i.imgur.com/ik7i4QW.jpeg) AKA “double square drive” AKA “hex shank”. You can see that the corners are rounded out to take a scalloped drive bit.
But, as others have said, one should never need to tighten or loosen it once installed. It serves as the backer for the bolt in the middle to press against when removing the crank, the so called “self extracting bolt”.
It says right on the cap…15mm for the big one, 8 mm for the small.
Open your eyes, man
To remove the cranks, you leave the outer cap in place and turn the inner bolt with a 8mm hex wrench counterclockwise. The inner bolt will push against the outer cap and pull the crank off the spindle. That’s how “self extracting cranks” work.
To remove just the outer cap, you need a 15mm hex wrench. It says so right there. Some of those outer caps are reverse threaded, not sure if Rotor is or not.