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showlow 08-21-20 12:55 PM

Is part of this self extracting bolt missing?
Hi. Am I missing part of this self extracting bolt? Turned ot counter clockwise to get it off.

Iride01 08-21-20 01:04 PM

I don't think it's a self extracting bolt. I think it might be for self extracting crank arms, but you took the wrong thing off.

Should be a cover with a bolt or nut (depending on type). You use a tool smaller than the tool to take the cover off and turn the nut or bolt beneath the cover.

The bolt or nut must be screwed all the way in and the cover must be all the way on. They loosen in the opposite directions, so when you loosen the nut/bolt, it pushes on the cover and also pushes the crank off the spindle.

But, I'm not guarantying that is a self-extracting crank. But at first glance it looked like it is.

If what you are holding is entirely one piece, then probably not.

showlow 08-21-20 01:15 PM

Thanks for the reply. It looks to me like this bolt is supposed to slide into another sheath or something.

Now the question is, is there any way to get it off w/o getting that nut.

Iride01 08-21-20 01:22 PM

Can't tell for certain in the pic, but if you don't have a cover, it is either missing or these aren't self extracting cranks.

Cover is essentially a disk with a big hole that threads onto the crank. The hole will be big enough to let you put a tool, hex key in your case, through it and into the socket of that bolt. Some covers use just a size or two bigger hex keys. Others might use something else like a pin spanner and hex key combo like below.

fietsbob 08-21-20 01:25 PM

I have had the blocking ring (like the one with the 6 holes in it )

strip out the threads in the crank arm ... instead of budging the arm off the spindle at all.

so on another bike, that self extractor, I took it out and put a regular bolt in. Octalink BB ..

may be same style.. Its all aluminum want it ?


Iride01 08-21-20 01:27 PM

If you are careful an old style crank puller will work. I've not used that specific type you seem to have, but you might can figure out something.

How close to a shop are you? Most probably have a bin of odds and ends just for when they run into missing things like this. Bike co-op?

showlow 08-21-20 02:07 PM

Thanks all. I texted my LBS. I think he has what's missing.

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