Idiot Alert! Help me save my power meter 🙁

So, armed with a crank extension pole and no clue …

I’ve over tightened the crank bolt of my fsa energy (stages) power meter to the point that the bolt has sheared itself free from it’s surrounding ring and borrowed itself deep into the spindle. Said bolt is also rounded at the threads and stuck too.

I’ve accepted that the spindle is gone (£60ish replacement) but can my pm be saved???

It’s fixed on the spindle tight with no bolt holding it on. I’ve reattached the crank and tried a few high torque spins up a nearby hill (carefully) trying to loosen the crank off the spindle but with no joy.

I’ve removed the extractor cap and taken a picture so you can see. Has anyone got any ideas how to get the pm off the spindle?

Many thanks. And I know! I’m a numpty :slightly_frowning_face:

I don’t know the FSA stuff, except one I had had a fancy loosening thing threaded backwards to get crank off.

Anyway, you’d get it off with some sort of bearing puller. Maybe best take to a small engineering shop and tell them what you want.

A windscreen wiper remover tool might work, but you might need to find a suitable size nut to sit in the hole, or grind the sides off a large nut to make it fit snug.

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The legs open up, you’d put them at back end of crank, and screw the handle and it will push spindle out.

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Could try differentially heating it; though with an all metal assembly it’d be pretty hard / elaborate (and may or may not work).

I’d probably find the largest hex bolt that fits inside the spindle, keep it in a freezer for a few hours, gently heat the end of the the crank (I’d probably submerge the end in hot but not boiling water for a few minutes), clamp the spindle, put the chilled bolt inside the spindle (hex head on the crank side) and try to rotate it off.

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Thanks folks, I’ll try the wiper puller tool first. Great idea!

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If it doesn’t work (it’ll probably be down to not getting enough purchase on the handle). Put a 1/2" drive bar from a socket set on the handle to give you more leverage.

A small cheap bearing puller should do it, they usually have 3 legs.

Here’s a cheap set of 3, one of them should do the trick… most important part is getting something decent of same diameter or a fraction smaller than the o/d of the spindle… a nut or a washer, or even double up a couple of washers so they don’t bend.

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Just looking at your pics again, are you sure their is nothing to stop that spindle from pushing through… I just remembered I had my old one in a box in the garage, is this what yours looked like?


If so you should be fine…… you done well to snap the stud :rofl:

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Would an old fashioned crank removal tool fit? If so you could screw that into the crank arm threads then gradually adjust it to push the crank arm off the spindle.

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I don’t think it’s the same size.

That FSA one is a strange design… you loosen part of it with a left hand thread, then loosen/tighten a bit right hand thread…or vice versa and it pushes the crank off as you turn it… but none of the threaded parts are meant to come off iirc.

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I had one (a FSA crank) about 10 years ago, so my memory could be hazy. IIRC it worked a bit like a inbuilt crank extractor. The OP looks to have managed to burst the top bit of it out. But if a non inbuilt extractor won’t fit, my idea won’t work. Perhaps a lbs might have something to help :neutral_face: If it’s any consolation to the OP the newer shimano cranks seem to fail catastrophically and at least they’ve got solid ones :neutral_face::neutral_face:

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Faced with this type of problems, there are 3 types of human beings: the Hitters, the Drillers and the Pryers. The Hitters think every problem can be solved with a hammer. Stay away from them. The Drillers can be pretty good, if they are well-equipped and well-trained. But by definition they destroy something along the way. And the Pryers - they will look forever for the one puller that fits this peculiar job; they do well, if and only if they can find the magical puller.

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:+1: :rofl:

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Have you tried a standard crank puller, or am I missing something? Standard extractor threads are M22 - the self-extractor should be 22mm outside diameter. If the extractor threads are good then you’ll just need something to plug the hole for the puller to push against.

Edit: Never mind, just discovered that FSA use an M27 extractor thread. I read on on forum that this is the same size as a Cannondale Si/BB30 puller, but others say that’s M30. But I did find this: a bung for the end of the spindle

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Success!!! I reached out to the tech department in my school (I’m a teacher) to see if they had any pullers. They didnt have any that fit, but Mr Phipps is definitely a hitter!

He rested it in a vice with the spindle pointing down, and used a chisel to hammer the buggered bolt. The spindle popped off phew!

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Result! :+1:

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Proving me wrong - sometimes a Hitter will provide a good solution. The chisel is an essential component of a Hitter toolbox.

And of course my analysis was short on all the variants that can mix in, such as Heater-Freezers and the unstoppable WD40 Sprayers.

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Not to mention, the dreaded angle-grinders.