One key crank??

[Rod Smith]

Can you remove the bolt and use a regular crank puller?

[Jason B]

Unfortunatly not, once the bolt is out there isn’t anything for the puller to push against.

[Rod Smith]

OK. The self extracting crank bolts I’ve seen worked with a traditional square taper bottom bracket spindle. I guess there are newer types. This link might help, http://www.parktool.com/blog/repair-help/self-extracting-or-one-key-release-systems

[GuyContinental]

@Jason B 32941 wrote:

Anyone have any experience with a one key crank also called a self extracting crank? I have an older 7700 dura ace crank that is, from what I am gathering it is a one key crank. Is removing it as simple a Allen wrench cranked counter-clockwise. I have only had cranks that needed a crank remover. I can easily remove the dust looking cap, and even the bolt underneath, but when I leave the dust looking cap on with bolt underneath and try loosening it with just an Allen wrench, it will loosen for a few turns and then stop when I get to the dust cap. I just want some confirmation that things are going right before I start really cranking.
Thanks for any advice

Jason,

I have an old XTR crank set up like that and my newer FSA BB30 cranks work that way as well (as pictured in the Park link above) – the bolt pushes against the ring and backs the crank off the splines. It works great (in fact I wish that all my bikes were set up this way) although you need a pin spanner to properly mess with the lockring. What you DON’T want to do is back that bolt out unless the lock ring is fully in place & flush with the crank surface- it usually only has a few threads and they won’t hold against serious torque- ask me how I know this I also had what turned out to be a catastrophic failure last year with a seized hollowgram bolt (super light aluminum)- I hoss’d it so much that I broke the bolt AND forced the arm spline to de-bond from the crank. Although my issue was personal idiocy combined with overly light parts and a manufacturing issue with the carbon bonding, take heed- if it doesn’t want to go with reasonable torque, you might want to get in there with some PB blaster to break it free.

As a minor note, I also like to grease the contact surface (where it touches the inside of the lock ring) of the bolt and use a touch of lock-tite (blue) on the ring threads.

[Jason B]

^^^^
Great advice!!!! I just noticed that my lockring was not totally screwed in after reinstalling it. That would have made me cry if I stripped it.
thanks

[GuyContinental]

@Jason B 32963 wrote:

^^^^
Great advice!!! I just noticed that my lockring was not totally screwed in after reinstalling it. That would have made me cry if I stripped it.
thanks

Try breaking a $700 crank… I mounted it’s sad remains above my bench with a sharpie note saying “Torque Much?” as a reminder…

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