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Old 08-17-12, 07:26 PM   #1
RJMurphy
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Stuck Crank: Advice??

I have a Sugino crank (non-drive train side) that connects with a square tapered bracket, but is stuck. It's an older Bianchi frame. 1980's. The dude who I got it from forgot to tell me that the threads for the crank remover are COMPLETELY stripped. So, needless to say, a crank removal tool is null. I can get the bolt out, but the crank is pretty stuck. I don't really want to bash on it with a hammer. I think that may hurt the frame. Advice anyone?? Thanks!!
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Old 08-17-12, 07:33 PM   #2
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Ball joint separator (pickle fork) from an auto supply store, chuck removal wedges or perhaps a 2-arm gear puller.
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Old 08-17-12, 07:55 PM   #3
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Remove drive side arm.
Unscrew lock ring & movable cup.
Pull out spindle.
Drive spindle out of the arm on a vise or similar.
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Old 08-17-12, 08:48 PM   #4
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Ball joint separator (pickle fork) from an auto supply store, chuck removal wedges or perhaps a 2-arm gear puller.

+1. gear puller is a poor man's crank removal wrench, but they work.

Don't try anything that includes a hammer as you are likely to damage the BB.
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Old 08-17-12, 09:35 PM   #5
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+1. gear puller is a poor man's crank removal wrench, but they work.

Don't try anything that includes a hammer as you are likely to damage the BB.
In my experience, Bill's advice above works very well. In the past, I've clamped the crankarm itself in a sturdy bench mounted vise and used a punch on the bb spindle and knocked the spindle out of the crankarm. It works only if it's a cup and cone bb. YMMV
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Old 08-17-12, 09:51 PM   #6
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A piece of wood and a hammer works like a charm.
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Old 08-18-12, 04:11 AM   #7
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In my experience, Bill's advice above works very well. In the past, I've clamped the crankarm itself in a sturdy bench mounted vise and used a punch on the bb spindle and knocked the spindle out of the crankarm. It works only if it's a cup and cone bb. YMMV
Yup. If we are talking the same method, I cracked a bearing cup doing that, so you can damage your BB if you use a hammer. Same thing if you use a piece of wood and a hammer.

If the BB is still assembled with the axle and bearing cones inside the BB, any "whack" you give the BB axle/spindle will put enormous force from one of the cones onto one side of the bearings and cups.

The last thing you want to do is crack a bearing cup or put flats onto the surface of some of your bearings. Better off using some kind of a puller.
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Old 08-18-12, 08:08 AM   #8
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Buy a pair of Jacobs Chuck removal wedges (less than $10.00) and you'll have that crank off so smoothly and easily that you'll be comfortable reusing it if you want to. They are 100% guarantied to remove any crank with zero damage to anything. It's been a while for me, but I think you need the #6 size, just confirm that the slot is 5/8" wide (they don't make them with a 9/16" slot).
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Old 08-18-12, 01:53 PM   #9
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I have never done this but I have read that if you don't want to reuse the crank, then you can take the bolt out or loosen it and then ride the bike a block or two and the crank will come loose. If this works the crank hole may be deformed which makes it unusable.
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Old 08-18-12, 02:06 PM   #10
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I have never done this but I have read that if you don't want to reuse the crank, then you can take the bolt out or loosen it and then ride the bike a block or two and the crank will come loose. If this works the crank hole may be deformed which makes it unusable.
This works in many cases, but DO NOT REMOVE THE BOLT so the crank doesn't come off entirely. Simply back it off about 1/16" or so so the crank can pop loose, but not come off. It can take serious pedal load to make this work, so do standing sprints, or look for a steep hill to chug up in a big gear. You'll hear/feel the crank come free, then can gingerly ride it home, and odds are it'll still be fine.
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Old 08-18-12, 06:37 PM   #11
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Yup. If we are talking the same method, I cracked a bearing cup doing that, so you can damage your BB if you use a hammer. Same thing if you use a piece of wood and a hammer.

If the BB is still assembled with the axle and bearing cones inside the BB, any "whack" you give the BB axle/spindle will put enormous force from one of the cones onto one side of the bearings and cups.

The last thing you want to do is crack a bearing cup or put flats onto the surface of some of your bearings. Better off using some kind of a puller.
I meant that you can take the bb spindle out of the bike, leaving the NDS (assuming it's the left crankarm) cup stuck loosely between the spindle race and the crankarm itself. I would not recommend doing it on a fully assembled bb.
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Old 08-21-12, 02:04 PM   #12
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You guys are all super awesome. Thanks a ton for sure!
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Old 08-21-12, 02:10 PM   #13
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You guys are all super awesome. Thanks a ton for sure!
So what worked in the end?
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Old 08-21-12, 04:23 PM   #14
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Another way to remove the cranks is supporting the whole bike in a vice only by the arm near the BB (bike held horizontally with the stuck crank facing upwards). Loosen the bolt and tap with a punch/hammer. The weight of the bike preloads the joint to come loose, an extra nudge with a hammer will pop it off. Bearings are tough, I've not yet mangled any BB's even while hammering cottered cranks unsupported.
And leave the bolt in as when it pops off, your bike will fell to the ground/workbench/you if the bolt is not there. The bolt will hold it (and only loosen it a bit, like 1-2mm, as when it pops off it may bend the bolt while supporting the bike if the bolt is far away out)

And another less impact method is a machinist C clamp bent sideways on the frame. that way you can hold the food on the inner part of the crank and applying force on the spindle (yet the bolt loosen still in it is a good idea as the other foot of any clamp will be generally larger than the BB spindle opening in the crank, and stacking a punch in between can get tricky to line-up with a bent clamp, that bolt helps a lot)
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Old 08-22-12, 06:09 PM   #15
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I just wedge some 14" motorcycle tyre-irons in between the cup & crankarm. Pry a little and >POP< goes the crankarm. Off in 2-3 seconds max with no damage to either part.
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