I used a hex wrench in the middle and felt it loosen and then tighten again – feels like it’s hitting against the ‘special’ fastener with the two circled indentations…do I need to remove that first? (What’s it called?). What tool do in need?
Thanks!
by SbluAus
4 Comments
Pin spanner
[https://www.parktool.com/en-us/product/pin-spanner-green-spa-1](https://www.parktool.com/en-us/product/pin-spanner-green-spa-1)
The hex bolt felt tighter because it was pushing against the ring with the two divots. It’s made to self extract that way. Just keep turning that hex until the arm is loose.
Edit: the ring is known as an “extractor cap”. Might be other terms for it, too.
Self extracting crank. All you need to do is keep going with the hex wrench loosening and the crank will come off.
As others have noted, this is a self-extractor. But if you do have the appropriate extractor tool for this crankset, I’d just go ahead and remove the self-extractor cap (which is basically a thick threaded washer with a hole in the center for the crank bolt head) and remove the crank the traditional way. You’ll need a pin spanner wrench that fits into the two little holes on its surface. If it’s stuck, hit it with a penetrating lubricant and let it sit for a day or two. Once the self-extractor out, make sure there isn’t a “true” washer underneath, between where the extractor was and the crank bolt head. You want to engage as many threads as possible with the extractor tool, so if a washer’s in there, remove it too.
It’s rare, but I’ve seen self-extractors not work, and you’re also depending on the person who assembled it years ago to have done it correctly (and that nothing went wrong with it in the meantime). If I’m using a crank extractor, I can be confident I’m doing it right. Not so much with an old self-extractor. You could also get started with the self-extractor and desist if it seems like it’s deforming (it’s aluminum, so it requires less force to fuck it up than you might expect).