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Removing bolt from crank
#1
I'm looking to take apart the bottom bracket on this 80's Supercycle. I'm having a difficult time removing the bolt from the crank. I managed to get the one out by pounding it with a hammer like a caveman.

However the bolt on the otherside won't even budge and I'm thinking there has to be an easier way. Any suggestions?

The crank does not run smoothly so I'm anticipating replacing after inspection. But I'm new to this and would appreciate any insight or info regarding the spindle or what I need to keep in mind.

Thanks!
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#2
You have what is called a cottered crank!!! Banging them with a hammer like a caveman works lol. There are easier ways but kinda expensive! Here is an excellent and much easier way to remove them... http://sheldonbrown.com/cotters.html .
Good maintenance to your Bike, can make it like the wheels are, true and smooth!
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#3
Yeh thats an old crank, if budget allows replace with sealed bottom bracket and a new sprockets and pedals. It is likely your BB races are worn. If OK clean and than replace bearings and use good marine bearing grade grease.

AS per removal soak overnight with a penetrating oil. Than try again. Heating pedal around the pin, not the pin will help too.

Use a block of wood to hammer on, do not hammer directly on pin.
Never Give Up!!!
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#4
As Bill noted, read this:

http://sheldonbrown.com/cotters.html

Base on the appearance of the cotter you have removed, I would surmise that the other one is toast too from not being periodically tightened. I doubt penetrating oil will make any difference.

As noted above; if at all possible within your budget, replace the cottered system with cotterless.
Nigel
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#5
Another option and I do have this tool and have used like 5 times already is this mega tool for cottered cranks...... http://www.bikesmithdesign.com/CotterPress/index.html . Bit on the expensive side but I recommend it to anyone.
Good maintenance to your Bike, can make it like the wheels are, true and smooth!
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#6
Bill; neat tool; I think that you could same effect with a heavy duty C clamp and another crank arm arranged so the cotter pin would go thru the second arm (or block with a hole in it).
Nigel
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#7
Wow, thanks for the replies everyone! I will try a method on the Sheldon Brown site and let you know how it goes.

Thanks for the tool tip Bill. I envisioned that a clamp of this fashion would be the solution. If I could get my hands on bikes with cottered cranks, I could see it being worth the investment for me.
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#8
Interesting cotter pin press, kind of a large chain tool. I have several engine gear pullers that would do this job too. Also a short piece of pipe or pedal ala Sheldon and a large C-Clamp as a press. Get that cotter..........Still suggest soaking in penetrating oil over night . Some top stuff really works well. Ask mechanics working on vintage cars and motorcycles.

Posting this info again:


"Machinist's Workshop magazine actually tested penetrants for break out torque on rusted nuts. Significant results! They arranged a subjective test of all the popular penetrants with the control being the torque required to remove the nut from a "scientifically rusted" environment.

Type of penetrating oil ..... Average load

None ................................ 516 pounds

WD-40 ............................ 238 pounds

PB Blaster .......................214 pounds

Liquid Wrench .............. 127 pounds

Kano Kroil .................... 106 pounds

ATF-Acetone mix......... 53 pounds

The ATF-Acetone mix was a "home brew" mix of 50 - 50 automatic
transmission fluid and acetone.

Note the "home brew" was better than any commercial product in this one particular test. A local machinist group mixed up a batch and all now use it with equally good results. Note also that "Liquid Wrench" is about as good as "Kroil" for about 20% of the price.

George E. T.
Live to ride, ride to live.
ABC # 5721
Venice, CA
Never Give Up!!!
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#9
Something else you will need for the bottom bracket pieces is this handy tool..... http://www.parktool.com/product/adjustable-cup-wrench-hcw-11 . Beware if memory serves me right one of them turns clockwise to come loose Wink . That model I believe has caged bearings! If it don't then all the bearings may just fall out as you are loosening it. No fear I will tell ya how to replace them without trouble Big Grin .

George is right, a little lube will make it come out easier. Nigel is right too it has to have good force put to it, great ideas on the c-clamp and gear pullers Smile . My luck is not the best when making my own tools lol.
Good maintenance to your Bike, can make it like the wheels are, true and smooth!
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#10
I improvised a method from Sheldon Brown and used a couple of bricks and a socket from a rachet set. Two taps with a hammer and this puppy popped out!

Thanks GeorgeET for posting the info. I'll note it for future reference.
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#11
Good use of a socket as a back up . Forgot to add that. Sockets are also great for driving in bearings and seals. Not as much on bicycles but on motorcycles.
Never Give Up!!!
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