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Shimano bottom bracket/ crank arm tooling

by Boatsie
Sun, Jan 28, 2018 08:28
6

I changed crank arms.
Square drive Shimano bottom bracket.
Using the crank arm remover that comes with the small bicycle tool box, I noticed the pushing bolt pushs onto the bottom bracket outer threads. I didn't like that! Having grown around tools and their functions, threads are important!
The donor bike arms were then removed. I used a small chunk of metal to broaden the push onto the boarder between the thread and the square perimeter. Worked perfect on the 1St arm yet failed and compressed into the thread on the last arm. Ruined it unless tapable. 3 ruined it.

Does someone know of a non thread touching crank arm remover used with Shimano square drive cranks please?
My thoughts at the moment are to grease the tools thread, weld a washer of less diameter than the square length and be happy with a non serviceable tool. I figure that should be okay as tool use is not often; nearing rare.

A further question I have is chain wheel. Having replaced 3 to a 2, assembled yet loose and awaiting greese and tightening. I was thinking of assembling with old cassette, very worn chain and worn chainwheels to replace after running in assembly and different shifters. Do I need remove crank arm to switch the chain wheels?

1 should have bought a new one. Argh

If you're new please join in and if you have questions pop them below and the forum regulars will answer as best we can.

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6 comments

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Roadie_john | 7 years ago
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That cap bit is dual function - it’s octalink one way round and threaded the other - you take the cap off, reverse it and slide it into the hollow octalink axle, or leave it on to protect the thread. Or take it off altogether if the axle takes nuts rather than bolts.

However, most crank pullers have a chamfer machined on them that’s enough to prevent the end of the puller distorting the thread...

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Boatsie replied to Roadie_john | 7 years ago
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Roadie_john wrote:

That cap bit is dual function - it’s octalink one way round and threaded the other - you take the cap off, reverse it and slide it into the hollow octalink axle, or leave it on to protect the thread. Or take it off altogether if the axle takes nuts rather than bolts.

However, most crank pullers have a chamfer machined on them that’s enough to prevent the end of the puller distorting the thread...

I'm with you. The cheap tool kit I bought just touches the threads when pushing the arm off. I need to spread the load. I've asked the old man; a retired fitter and turner, to build me a tool: a scrap bit of tube welded to a washer.

I'm ignorant of other bottom bracket types. Hoping other newbies recognize what they have and don't ruin or need to read tap their equipment.
Thank you with the advice guys/girls.

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ktache | 7 years ago
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Park ccp-2.  

And its much easier to remove rhe chainset to change the chainrings.  You might need a park cnw-1 to hold the other bit other than the hex side.

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StraelGuy | 7 years ago
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Do you have a link to the crank remover you are using? They're pretty simple really. The body of the tool should screw into the cap threads and the inner part of the tool should push against the end of the axle - not a lot to go wrong really.

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Boatsie replied to StraelGuy | 7 years ago
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StraelGuy wrote:

. The body of the tool should screw into the cap threads and the inner part of the tool should push against the end of the axle - not a lot to go wrong really.

I understood that. My argument is that the inner part is just a tad too little diameter and touches on the axle thread. If the tools inner bolts diameter was 2-4 mm (guess) wider the the face upon which the bolt pushes is much sturdier and I can reduce my risk of damaging the bottom bracket axle thread.

The thread was pushed on during the initial removal of the arms. Heaps of thread there. Not risking the damage. Just weighing up options..

Cheers ktache. Park ccp-2 looks easy. I think taking a spare crank arm into the LBS could be my go, size up a wider pushing face if available.
Welding a washer if they're dear though 1

Found this.
https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.com.au%2F...

That cap bit a heaps better idea than a welded washer. Could lube the tool!
I think I'll search scrap and use a washer and tube. I haven't a clue why the thread protector isn't included in the cheap tool boxes. Best bit.

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ChasP replied to Boatsie | 7 years ago
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Boatsie wrote:
StraelGuy wrote:

. The body of the tool should screw into the cap threads and the inner part of the tool should push against the end of the axle - not a lot to go wrong really.

I understood that. My argument is that the inner part is just a tad too little diameter and touches on the axle thread. If the tools inner bolts diameter was 2-4 mm (guess) wider the the face upon which the bolt pushes is much sturdier and I can reduce my risk of damaging the bottom bracket axle thread. The thread was pushed on during the initial removal of the arms. Heaps of thread there. Not risking the damage. Just weighing up options.. Cheers ktache. Park ccp-2 looks easy. I think taking a spare crank arm into the LBS could be my go, size up a wider pushing face if available. Welding a washer if they're dear though 1 Found this. https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.com.au%2F... That cap bit a heaps better idea than a welded washer. Could lube the tool! I think I'll search scrap and use a washer and tube. I haven't a clue why the thread protector isn't included in the cheap tool boxes. Best bit.

 

'That cap bit' is available seperately but will wreck your cranks, it's an adapter for hollow octalink type bottom brackets and won't go through the sqare taper. Your tool is an old design for bottom brackets which had external threads and nuts holding the cranks on, not bolts. I've got one of these which works really well https://www.decathlon.co.uk/bike-crank-extractor-id_8350528.html the smaller diameter just fits through a square taper and the step works for octalink.

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