Crank Removal Problems

[David9694]

I did wonder if anyone had ever tried recutting the crank threads?

I didn’t know the tapered puller existed (upthread) but I think in this instance it was beyond any redemption.

The next candidate is a very nice Ultegra octalink. I think they’re meant to be self-extracting - but no. I’ve not come across this system before so advice welcome. The M15 bolt wears a threaded collar. On one side, the collar I found to be on the wonk - there seemed no option but to remove both, which on the wonky side needed a fair bit of torque.

But with the hollow axle, the crank puller has nothing to bite on. The next step seems to be a Shimano part that sits on the end of and widens the nose of a standard crank puller - I assume that’s the difference as regards the dedicated ISIS pullers.

Var and Cyclus sell a crank puller set that actually cuts bigger much coarser threads in damaged cranks. Works very well but costs A LOT and the same puller has to be used in the future with the crank, although some self extracting bolts are provided with the same new puller thread pitch..Screenshot_2021-04-24-14-23-24-618_com.ebay.mobile.png

It sounds maybe as if your octalink bolts are self extractors but the collars were installed badly or weren't up to the job. Most normal octalink bolts are indistinguishable from regular square taper bolts from the outside.
To remove an octalink crank without the correct puller you can just use a thick washer of the right size for a normal square taper puller to bear against, laying the bike on its side and obviously taking care that the washer doesn't move out of place as you nip the puller up.

C. £150 for the VAR PE-11000 kit - you weren’t kidding! This looks like it re taps to M24.

I see there’s a 23mm old TA standard (and a Stronglight 23.38mm standard) and that Spa do a £17 Var extractor with the 23 mm. An M23 x1.0 tap is £45 from China. Just a thought.

[rjb]

I don't think a tap would work. Most taps are slightly tapered so it would mean only the top couple of threads at best would be fully formed in the crank before the tap bottomed out on the crank seating face.

[GideonReade]

I don't think a tap would work. Most taps are slightly tapered so it would mean only the top couple of threads at best would be fully formed in the crank before the tap bottomed out on the crank seating face.

Yes, the only way an ordinary shape tap would go in would be to drill out the square taper section to the blank diameter.
But... I really don't know, as aluminum is soft, much softer than any steel (?), is it possible to make a single use tap by taking a bolt (steel), and filing some teeth into it? Maybe do it twice, turning a slight taper on the first one. Just an idea, no idea if viable.

[fastpedaller]

It may be cheaper to buy a new crank compared with getting a bolt or tap of the correct size?

[GideonReade]

Well, I guess many of us are trying to match up something nice from way back when. Mine was a nice MTB STX crankset, but 8 speed.

[Pebble]

I can't see how you could retap it unless you went to a bigger size, when the crank puller stripped all the threads from the crank, material was lost so the hole is now too big.


As to how I am dealing with the problem. Well I just painted the BB with the crank on, put it all back together and that was 200 mile ago. I will get a new crank and BB in stock for when the time comes. If a two leg puller doen't get it I will try the nut removal and ride, and if that doesn't work will just cut it off (probably through the BB for quickness)

But in the mean time, which could be another 20,000 miles (4 years) until the BB fails, then there is not much point trying to get it off.

[David9694]

I’m pretty sure the Octalink bb is pretty firmly stuck, but I can scrub round that.

https://www.ebay.co.uk/itm/293696709084 - windscreen wiper remover looks like the right sort of size if those feet will fit snugly around a stuck crank. I’ve ordered a different one with flexible legs. I’m going to get the Cycle store tapered remover as well.

The little Shimano stud arrived today - as I suspected, the normal puller further stripped the threads.

[David9694]

Tried the wiper blade remover to no avail. Is I’d hoped, it was the right size for getting its arms into the space behind the crank, but it was hard to keep it straight when it came to bearing down on the stud inside the crank.

I think the next step is going to be build it up and see if riding on it without the crank bolt does the trick.

[David9694]

I took some good advice on this forum and whenever removing STCs I carefully insert the tool - pinch it up - screw in the extractor and pinch it up tight then hit the end of the puller with a small hammer.

When this fails (which it does very occasionally on very old cranks) and the thread is a gonner, I repeat the process but using a Unior tapered extractor.

A great tool that has never failed me

https://www.cyclestore.co.uk/unior_tape ... qjEALw_wcB

+++++1 on the Unior tool. It screwed in a decent way and with the help of the Shimano stud that sits on the end of the Octolink axle, it has removed the l/h crank. As a bonus, it seems to have fixed the threads so that the regular remover fits snugly.

I’ve swapped out the 9s chainrings from an another 10s chainset I had lying around. I’ve tried the bottom bracket - not much sign of movement there.

[gregoryoftours]

That Unior tool sounds really good, and way cheaper than the full on and expensive VAR tool kit. Plus keeps the same thread size/pitch. Doesn't the top hat shape of the stud on the end mean that it works for both square taper and octalink with no other parts needed?

[David9694]

That Unior tool sounds really good, and way cheaper than the full on and expensive VAR tool kit. Plus keeps the same thread size/pitch. Doesn't the top hat shape of the stud on the end mean that it works for both square taper and octalink with no other parts needed?

No, it’s not big enough, you need the stud for Octalink.

[UpWrong]

Had this happen on a new Wisper electric bike. Crank bolts were over-tightened. Got the bolts out eventually but the crank puller has pulled out the threads from the left crank. Dremelling the left crank off is probably easiest. That still leaves me needing to get the right crank off. I noticed that the extractor tool can take a 14mm Alley key/driver in its end. So woindering if that might be better than using the spanner on the end of the tool since the latter generates a lateral force as well as a turning force? Rather cheesed off about this. Clearly way overtightened.

[Jdsk]

Had this happen on a new Wisper electric bike. Crank bolts were over-tightened. Got the bolts out eventually but the crank puller has pulled out the threads from the left crank. Dremelling the left crank off is probably easiest. That still leaves me needing to get the right crank off. I noticed that the extractor tool can take a 14mm Alley key/driver in its end. So woindering if that might be better than using the spanner on the end of the tool since the latter generates a lateral force as well as a turning force? Rather cheesed off about this. Clearly way overtightened.

When you say "spanner"... what's the fitting on the end of the tool... flats for a spanner or male hex for a socket? (In addition to that female hex socket for a key. )

Thanks

Jonathan

[UpWrong]

Had this happen on a new Wisper electric bike. Crank bolts were over-tightened. Got the bolts out eventually but the crank puller has pulled out the threads from the left crank. Dremelling the left crank off is probably easiest. That still leaves me needing to get the right crank off. I noticed that the extractor tool can take a 14mm Alley key/driver in its end. So woindering if that might be better than using the spanner on the end of the tool since the latter generates a lateral force as well as a turning force? Rather cheesed off about this. Clearly way overtightened.

When you say "spanner"... what's the fitting on the end of the tool... flats for a spanner or male hex for a socket? (In addition to that female hex socket for a key. )

Thanks

Jonathan

It's flats for a spanner at the end of the extractor tool. I used a 12" adjustable spanner on them, whacking the end with a rubber mallett.

I've had a go with the right crank after warming it with a hair dryer. It's not shifting. I abandoned for now rather than risk pulling the threads out on that side too.

I'm pondering whether to buy a bearing puller and/or a unior tapered crank puller

[Jdsk]

Thanks

I'd prefer a solid open-jawed spanner over anything adjustable.

But I wouldn't expect to exert more force with a hex key turned by hand than with that 12" spanner.

Jonathan