Square taper BB

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The Rookie
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Square taper BB

Postby The Rookie » Mon Oct 08, 2012 10:45 am

What thread is the standard crank retaining bolt, trying to help a friend remove the BB and the previous owner has mullered the spline pattern somewhat so I want to buy a bolt to lock the BB tool in place.

Uli
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Re: Square taper BB

Postby Uli » Mon Oct 08, 2012 11:40 am

Standard right hand thread (at least the last I was dealing with). Maybe crank removal tool and some sort of washer could help you.

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supersonic
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Re: Square taper BB

Postby supersonic » Mon Oct 08, 2012 11:45 am

M8.

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The Rookie
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Re: Square taper BB

Postby The Rookie » Mon Oct 08, 2012 11:50 am

That's what I thought SS but a stnd M8 bolt won't go into the end of either my spare square or the one I want to remove, unless its a friction thread?

Uli, thanks, but have a think and realise that's not happening!

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mrmonkfinger
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Re: Square taper BB

Postby mrmonkfinger » Mon Oct 08, 2012 12:10 pm

new bolt, £6

http://www.chainreactioncycles.com/Mode ... elID=34652

comes with free bottom bracket...


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nicklouse
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Re: Square taper BB

Postby nicklouse » Mon Oct 08, 2012 12:30 pm

The Beginner wrote:What thread is the standard crank retaining bolt, trying to help a friend remove the BB and the previous owner has mullered the spline pattern somewhat so I want to buy a bolt to lock the BB tool in place.

splines?

what are you actually trying to do?
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Uli
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Re: Square taper BB

Postby Uli » Mon Oct 08, 2012 12:31 pm

Uli, thanks, but have a think and realise that's not happening!

Try asking again so people actually know what is happening...

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benpinnick
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Re: Square taper BB

Postby benpinnick » Mon Oct 08, 2012 12:46 pm

Zipties round the tool can be surprisingly effective.
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njee20
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Re: Square taper BB

Postby njee20 » Mon Oct 08, 2012 12:53 pm

Try asking again so people actually know what is happening...


+1

Splines? Tool slipping? Lost me.

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mrmonkfinger
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Re: Square taper BB

Postby mrmonkfinger » Mon Oct 08, 2012 12:54 pm

The Beginner wrote:Did you even read the frickin post FGS? 4r5e!


Ok, clearly a sense of humour fail, so I'm out.

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nicklouse
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Re: Square taper BB

Postby nicklouse » Mon Oct 08, 2012 12:56 pm

Ahhh right got it now. a bolt and washer to go through the BB tool to hold it against the BB cup to get extra perchace.

M8 is the standard but many dont use that standard but use others rincluding M12 and M14 and maybe a few others.

What are the cranks and fitting?
"Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."

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The Rookie
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Re: Square taper BB

Postby The Rookie » Mon Oct 08, 2012 13:18 pm

Thanks Nick for reading my post.

Uli I'm removing the BB not a crank, mr finger, how would a crank bolt help me remove the BB which it clearly states I want to do by bolting the tool in place?

If I try an M8 it binds up after 2 turns, it's a square taper but no ID as the rest is buried inside the Giant frame. Cranks are Shimano SIS one piece of indeterminate age (don't have ID as they were binned as we are fitting new ones), but guess at mid to late 90's.

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stubs
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Re: Square taper BB

Postby stubs » Mon Oct 08, 2012 13:31 pm

Might just be full of rust and crap. Try running an M8 tap in if you can get your hands on one. Sometimes its easier with damaged splines to clamp the BB tool in a vice and use the frame as a spanner you can get someone to press down on the other end of axle while you wiggle the frame backwards and forwards to break the seal on the threads.
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The Rookie
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Re: Square taper BB

Postby The Rookie » Mon Oct 08, 2012 13:39 pm

Stubs, good call on a vice......

I'll try the bolt again, have a spare arm to hold the axle with.....

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mrmonkfinger
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Re: Square taper BB

Postby mrmonkfinger » Mon Oct 08, 2012 13:42 pm

The Beginner wrote:how would a crank bolt help me remove the BB which it clearly states I want to do by bolting the tool in place?


You didn't say you already had any bolts. You just said you wanted a bolt that fitted, to lock the tool in place. I have no idea how long a bolt you want. You've already said it isn't M8 thread. A crank bolt would definitely fit.

Personally I'd just use an impact driver, seeing as you're trashing the BB anyway.

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The Rookie
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Re: Square taper BB

Postby The Rookie » Mon Oct 08, 2012 13:55 pm

Crank bolts would be far too short.....a stock BB tool being well over an inch long, as the splines are mullered already, one slip with an impact driver would be curtains, so I'll pass on that ta.

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nicklouse
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Re: Square taper BB

Postby nicklouse » Mon Oct 08, 2012 14:23 pm

you have checked the threads of the crank bolt against the new bolt?

if they are the same then the threads in the BB are in need of TLC or a bit of brut force.
"Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."

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nicklouse
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Re: Square taper BB

Postby nicklouse » Mon Oct 08, 2012 14:25 pm

The Beginner wrote:Thanks Nick for reading my post.


I did have to re read it a few times to finally get it.

your topic heading puts the mind in the wrong direction.

Buggered BB splines would have worked better.

is the axel hollow? would not have thought so.
"Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."

Parktools :?:SheldonBrown

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stubs
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Re: Square taper BB

Postby stubs » Mon Oct 08, 2012 14:52 pm

nicklouse wrote: a bit of brut force.


Wouldnt plus gas or WD40 work better than aftershave
Fig rolls: proof that god loves cyclists and that she wants us to do another lap


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