shoot me now....

Unclejack

Retrobike Rider
So, i got the latest donor bike home late last night and merrily started attacking it. Got the crank cover caps off, those shiny Shimano ones with the two holes in and screwed the extractor in. Not too tight and then got the spanner and started to tighten the middle. Only to see the extractor pull itself out of the crank along with the thread.

AAARRRGGGHH! Yes, you guessed it I'd forgotten to take the bloody crank bolt out. Complete numpty.Lucky it was the left so a new arm can be matched up.

So, I know there was a thread a bit back on this subject but has anyone local tried a legged puller on a crank before, I have a couple I'm gunna try tonight. Or had one retapped to 23mm so you can then use an old TA extractor, or had a crank helicoiled? Or failing that it'll be the angle grinder.

And lastly is there a "crank swap" thread somewhere as I also have a black LX chainset where the lefts fine and not that worn but as the threads have gone on the right I never used it and its surplus. Im sure someone will have the ying to my yang if you catch my drift.
 
shoot uncle jack

i will keep my 12 gauge under and over in the cabinet if you promise not to mess about with it!

i mean, if it is generic crank arm, shimano alloy stuff then cut it off. you can replace quickly from our wanted section. and even if it is m900 and suchlike the threads have had it, right? i know there will be a sympathetic solution that will also be long winded but, im for the hacksaw treatment ;)

first, get a good hacksaw blade in there, tungsten carbide are good, but use whatever works. then, get chopping from the outside in as close to the bb as you can. once the metal waste hits the floor grab the arm at the pedal end and press firmly toward the bike, then back, and repeat.

the remain of the taper will stretch very quickly and it will pop off!

i've done this on 'nakedgav's' KONA and worked a treat and quickly.

the hardwork is in the cutting. after that you can get on with things. but im talking 10 mins-ish
exhibit 1 below.
 

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to clarify, I want the cranks, not the frame. I can easily cut the cranks off etc, I just wanted to get them off cleanly and then be able to reuse them. and yes they are only "cheap" cranks but theres nowt as cheap as the ones you already own... :)
 
Try taking the crank bolt out and then take the bike for a ride. The crank often loosens itself and falls off ;)
 
so.. are the drive-side threads ok then? if so, and, it's just the crank arm that has blown it's threads...replace it! by the time you have messed about sourcing special tools etc..you could pick up a crank arm for postage costs.

let us know if both extractor threads have gone. and, ask yourself this...

am i ok using these arms again with knackered threads? you may need to change a chainring at some point. or, am I jumping too far ahead? do you intend to use until the rings are mashed anyway? if so, fair enough.
 
What are the cranks ? and what is the bottom bracket.
You could undo the far side of the bottom bracket shell
Take the crank bolt out... actually no, thread it in and then undo it a turn or two.
Get a big bar/socket set/hammer chisel/..
place it against the bolt, then hit the bolt.. tappity tap and a whack..
the crank should push against the bottom bracket shell and axle should keep going. It only need to be a bit to loosen it enough for either the tool to be used again or it falls of. Just in case, keep undoing the bolt a turn and tap again till that happens. (that should be common workman sense but well ;))

(and I did have to chuckle :LOL: )[/i]

type of bottom bracket might make this not practical, like modern cartridge shells. But old cup/cone would be good.
 
I have just the tool you can borrow, a ball joint spliter, just drive this between the crank arm and the frame it will fall off, or failing that bring it to my workshop I am sure the air saw and the air chisel will get it off :twisted: :twisted: ask Marc two tone about the air chisel lol
 

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slmracing":zdrweu91 said:
I have just the tool you can borrow, a ball joint spliter, just drive this between the crank arm and the frame it will fall off, or failing that bring it to my workshop I am sure the air saw and the air chisel will get it off :twisted: :twisted: ask Marc two tone about the air chisel lol

yep. im now hard of hearing but the seized bb cup was history ;) could crack the hull of a ship that chisel. :LOL:
 
Thanks for the offers of help people. With more time on my hands I got home last night (didn't even take my suit off) and headed for the garage. got the ball joint splitter out and lump hammer. made sure the splitter had flat against crank and started flogging. came off easy. Marked the (scrap)frame so its not a suitable method for future but job done. Now have to see if (my dads) 2/3 legged puller will get it back off the good frame in future. My latest budget build continues..!

Please address your complaints about me killing a perfectly good '90's tiawanese frame to...

* I mean I didn't get changed out of my suit into some work clothes, not that I regularly go into the garage naked. That would be a different lifestyle choice...
 
* I mean I didn't get changed out of my suit into some work clothes, not that I regularly go into the garage n*ked. That would be a different lifestyle choice..

And the term ball joint splitter would have a whole new meaning :D :D

At least it's off now, like you said not the best way but good as a last resort
 
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