Bicycle Mechanics - question about removing octalink crank arms

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gman26
09-11-10, 04:02 PM
Do you need a gear puller? I removed the retaining bolts, but they're stuck on there. It's a specialized rockhopper 29.


Jeff Wills
09-11-10, 04:24 PM
Do you need a gear puller? I removed the retaining bolts, but they're stuck on there. It's a specialized rockhopper 29.

You need the correct crank puller. Read on: http://parktool.com/repair/readhowto.asp?id=120

gman26
09-11-10, 05:55 PM
Mission accomplished! My local REI store had the tool and the mechanic was nice enough to remove the bottom bracket for free.
I love REI!


MudPie
09-11-10, 06:49 PM
Mission accomplished! My local REI store had the tool and the mechanic was nice enough to remove the bottom bracket for free.
I love REI!

What?!?! You missed an opportunity to buy a new tool!

gman26
09-11-10, 08:43 PM
What?!?! You missed an opportunity to buy a new tool!

I did buy the crank arm tool.

well biked
09-11-10, 09:02 PM
My Octalink cranks have always had self extracting rings; all you have to do with these, with the self extractors in place, is unscrew the bolt and the crankarm will back off the spindle.

MudPie
09-11-10, 10:05 PM
I did buy the crank arm tool.

Whew, all is right in the world nowl. I misread your post - thought REI mechanic had the right tool and took the arms off for you.

Kip
09-12-10, 02:42 AM
My Octalink cranks have always had self extracting rings; all you have to do with these, with the self extractors in place, is unscrew the bolt and the crankarm will back off the spindle.
I don't have this on my Octalink cranks. Can these self-extracting rings be retrofitted into what I have? It would make it easier to break down my bicycle for shipping when I tour.

reptilezs
09-12-10, 06:17 AM
crank usually dont need to be removed for shipping but you can install self extracting caps from various manufactures

Jeff Wills
09-12-10, 07:02 PM
I don't have this on my Octalink cranks. Can these self-extracting rings be retrofitted into what I have? It would make it easier to break down my bicycle for shipping when I tour.

Yes they can, but the issue with "self-extracting" crankarm bolts is that people rarely tighten them enough. Once the crankarm gets loose and the machining at the spindle interface gets boogered, it's all over. You have to replace the crankarm.

In general, most people don't remove the cranks when shipping a bike. Taking off the pedals is all that's needed.

Kip
09-12-10, 08:44 PM
Thanks for the information and cautionary note about the "self-extracting" crankarm bolts. I've never had to remove the cranks for shipping but I now have a bike with S & S couplings and am experimenting with how to pack it as compact as possible.

well biked
09-12-10, 08:58 PM
....... the issue with "self-extracting" crankarm bolts is that people rarely tighten them enough. Once the crankarm gets loose and the machining at the spindle interface gets boogered, it's all over. You have to replace the crankarm........

I've never had any problems with Octalink self-extracting cranks, I'm not getting what you're saying. The extractor ring is a a separate piece from the crank bolt; it needs to be snugged down against the crank bolt. How does the self-extracting feature have any affect on how tight you tighten the crank bolt?

http://i414.photobucket.com/albums/pp226/wellbiked/ImportedPhotos00039.jpg

prathmann
09-12-10, 09:10 PM
Yes they can, but the issue with "self-extracting" crankarm bolts is that people rarely tighten them enough. Once the crankarm gets loose and the machining at the spindle interface gets boogered, it's all over. You have to replace the crankarm.

My bikes don't have Octalink cranks, but one of them is my travel bike that requires removal of the crankarm to fit inside a regular suitcase. It has a self-extracting bolt on a regular square-taper crank and that's been used dozens of times when packing the bike. I don't really see why the self-extracting nature of it has anything to do with how tight I get it when reinstalling the crank. I'd use the same torque when tightening it regardless of whether I used a separate extractor tool to take it off or used the self-extracting bolt - but the latter certainly makes it quicker and more convenient to take the crank off when packing the bike.

Jeff Wills
09-12-10, 11:03 PM
I've never had any problems with Octalink self-extracting cranks, I'm not getting what you're saying. The extractor ring is a a separate piece from the crank bolt; it needs to be snugged down against the crank bolt. How does the self-extracting feature have any affect on how tight you tighten the crank bolt?


The typical 8mm hex (Allen) wrench is 6 to 8 inches long. It's tough to generate the required 25 to 35 foot-pounds of torque that is required with that short of a wrench. The self-extracting feature isn't really the problem, but it necessitates the hex (Allen) bolt. This makes people believe that simply hand-tightening the bolt will secure the crank when it doesn't.

nhluhr
09-13-10, 08:44 AM
I've never had any problems with Octalink self-extracting cranks, I'm not getting what you're saying. The extractor ring is a a separate piece from the crank bolt; it needs to be snugged down against the crank bolt. How does the self-extracting feature have any affect on how tight you tighten the crank bolt?

http://i414.photobucket.com/albums/pp226/wellbiked/ImportedPhotos00039.jpgI think he means if you don't screw in the self-extractor far enough and try to pull a crank-arm, you will strip the threads in the crank and then you won't be able to remove the crank easily. But that goes for using any kind of threaded extractor. A mechanical dolt will quickly ruin anything.