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Cranks removal, what to do now?

reaperactualreaperactual Posts: 973
edited 25 August in MTB workshop & tech
Planned to replace my knackered X-Type bb last night. Wish I hadn't started it.

Done this job a few times without any issues. This time on my own bike I had to use a pry bar just to get my crank bolt off. I guess it was cross threaded on initial installation?

Next my ISIS crank puller was hard to thread in and then twisted out easily on use and has now totally stripped the crank arm threads. 😭






I've tried brute force with hammer and crow bar, the spindle is still stuck fast and hasn't budged at all.

I ain't got a blow torch to try heating it up. Wondered if there's any other tips or tricks to try before I go to the local garage and see if they can do it with a three armed gear puller maybe? πŸ€”

The ds crank arm (and probably the chainring) are trash now, a bit gutted but mainly want the cranks off and don't want to damage the frame by using any more gorilla tactics. Any advise appreciated as always, thanks!

Posts

  • me-109me-109 Posts: 1,426
    Turn bike upside down, apply heat to crank centre/end of axle by hot air gun/ blowtorch/ hairdryer and use hammer to inner face of crank. Should be able to manage that without dazzling paint.
    Other option is to use grinder and cutting disc to split crank along the axle (or cut through the axle directly if you have space).
  • reaperactualreaperactual Posts: 973
    edited 25 August
    Thanks for the quick reply, hoping to sort this today if possible.

    I'll try and find a way to apply heat somehow. I did hit the back side of the crank behind the chainring by hitting a crow bar with a hammer, not even moved a tiny amount but suppose it really needs some heating to help it too.

    I may be able to cut through the top of the crank arm at certain angle but I would only be using a hacksaw as it's all I have tool wise. Maybe that would work? Can't see anywhere to cut through the axle itself.

    I'll give that a whirl later, thanks again @me-109. 😎
  • mully79mully79 Posts: 462
    That sucks,
    I would have probably holesawed down the crank but if you've only a hacksaw (hopefully a full size one) and cant get near the axle I'd cut the crank in the centre in the direction of the axle. (perpendicular to crank arm)
    It should be the easiest cut to avoid damaging anything else.
  • reaperactualreaperactual Posts: 973
    edited 25 August
    mully79 said:

    That sucks,
    I would have probably holesawed down the crank but if you've only a hacksaw (hopefully a full size one) and cant get near the axle I'd cut the crank in the centre in the direction of the axle. (perpendicular to crank arm)
    It should be the easiest cut to avoid damaging anything else.

    Yes Mate. As soon as I saw the crank puller twist off centre I knew it was gonna be a nightmare.😬

    Been sawing with little progress, (small hacksaw) whacking for the last two hours and got about 2mm of play to show some movement. May give it a little rest, have a bacon sarnie and a brew then try again.

    Trying to source a blow torch atm as I reckon that would really help get it done.
  • NcovidiusNcovidius Posts: 131
    See if you can get hold of a reciprocating power saw. I use those to cut seized bits off my car. It will make mincemeat of the spindle, and should easily fit between the base of the crank and frame.
  • reaperactualreaperactual Posts: 973
    edited 25 August
    Just hit the same knuckle twice with the hammer in quick succession, reckon I should give it a rest for today and have a blast tomorrow.

    Got a builder living next door so maybe I'll ask them to borrow a reciprocating saw or blow torch later.

    For now I only see see a tiny gap between the bb cup and inside of the chainring but that's where the dm lock ring is so not sure it's doable at the moment:-




    Maybe I can get a gap to open up on either side with more hammering and get the blade down there. Thanks for the idea, it could be needed.πŸ‘
  • reaperactualreaperactual Posts: 973
    edited 25 August
    Just had a look. This is the nds and looks to be the thick part of the crank arm and no exposed spindle yet:-


  • jcreillyjcreilly Posts: 1
    Ncovidius said:

    See if you can get hold of a reciprocating power saw. I use those to cut seized bits off my car.

    Oh. So you didn't buy the Bentley Turbo R you were talking about on Pistonheads after all, then? Internet fantasist returns to haunt online forums again and again, shocker.

  • me-109me-109 Posts: 1,426

    Just had a look. This is the nds and looks to be the thick part of the crank arm and no exposed spindle yet:-


    Is this Octalink or something where both cranks fit to the axle, not one end permanently fixed? Might be easier to attack the NDS, cut that off, remove the cup and batter the DS crank and axle out to remove the other half.
  • reaperactualreaperactual Posts: 973
    edited 25 August
    me-109 said:

    Just had a look. This is the nds and looks to be the thick part of the crank arm and no exposed spindle yet:-


    Is this Octalink or something where both cranks fit to the axle, not one end permanently fixed? Might be easier to attack the NDS, cut that off, remove the cup and batter the DS crank and axle out to remove the other half.
    A Race Face Ride Cinch crankset. Two piece with a 24mm diameter spindle just like Hollowtech II.

    The difference is an ISIS spindle with splines on the ds and the crank arm pushed on with a centre crank bolt with the nds crank arm bonded to the other end.

    I double checked the section on the nds with this pic on Google and the axle isn't exposed up to now:-


  • mully79mully79 Posts: 462
    edited 25 August
    i would cut here. should be like butter on aluminium.(with normal hacksaw)


  • reaperactualreaperactual Posts: 973
    edited 25 August
    mully79 said:

    i would cut here. should be like butter on aluminium.(with normal hacksaw)


    That's what I thought too but this is as far as I've got with the hacksaw method:-



    May need to put some more elbow grease into it and try a little harder. At that stage I was just hacking at it out of frustration.😬
  • mully79mully79 Posts: 462
    Those little hacksaws are rubbish.
    Treat yourself. really not worth the sweat at Β£12.99
    https://www.screwfix.com/p/bahco-24tpi-metal-plastic-hacksaw-12-300mm/88800
  • reaperactualreaperactual Posts: 973
    Nice one Mully, now that's a proper hacksaw! πŸ˜‹ No wonder I'm not getting anywhere with the little piece of sh#t thing here.

    Screwfix literally a mile down the road so reckon it's worth buying one. Thanks for the link Mate. πŸ˜ŽπŸ‘
  • lesfirthlesfirth Posts: 1,204
    I am not totally familiar with the set up you have here, so if I am talking rubbish ,just ignore me.
    Try unscrewing both bottom bracket cups with some water pump pliers ( google them if you don't know what they are). The cranks will limit how far you can unscrew them but if you carry on to unscrew them more it will force the cranks apart. With a bit of luck and maybe some heat things will come apart.
  • reaperactualreaperactual Posts: 973
    edited 26 August
    Thanks for the reply @lesfirth. That same idea has crossed my mind too.

    I've no need for water pump pliers. I did Google them and I do have an old rusty set, just didn't know that's what they were called.

    This Race Face bb is basically the same as a Hollowtech II as the Shimano SM-BB52 version was the one I planned to replace it with.

    I have the notched crescent shaped Shimano bb removal tool which fits. I could try it except I haven't because a bit wary of stripping the bb or shell threads trying to force them to push the cranks apart.πŸ€”

    I could give it a go but would be cringing with every turn thinking the last thing I need is to add another issue to this pig of a job.

    Luckily Mrs Reaper has got me access to a 110v angle grinder tomorrow at her workplace so plan to cut through the crank arm in seconds with a cool shower of sparks....truth is, quite looking forward to that. 🀟😝🀟
  • reaperactualreaperactual Posts: 973
    Update:

    That was a battle all the way to the bitter end even with a massive angle grinder:-






    Got it done:-



    Thank you all for your help and ideas. Much appreciated.🀟😎




  • mully79mully79 Posts: 462
    Good job ! That crank didnt want to let go at all did it.
  • lesfirthlesfirth Posts: 1,204
    Well done! This should be in "things that make you smile".
    I have never paid anyone to fix a bike. Who needs a LBS?
  • NcovidiusNcovidius Posts: 131
    Yep, smack it with a hammer to the n’th degree++++
  • me-109me-109 Posts: 1,426
    Nice one, made it pay for the grief it gave you. Had to grind off an FSA Vero square taper when the puller threads gave out. I know how you feel.
  • reaperactualreaperactual Posts: 973
    edited 28 August
    Thanks all. Don't know what happened to make it soo difficult? Maybe no grease and some sort of cold welding took place? Anyway hope not to have to deal with that again.

    It was a great spark shower and very satisfying with that last blow of the sledge hammer and it falling off.🀟

    Yep, no lbs for me, never been desperate enough so far. Nothing they could have done that we can't do ourselves with the right tools, big hammers (and even bigger angle grinder on this occasion). Treated the Missus to a bottle of Pink Gin so worked out a cheap fix. πŸ˜ƒ

    Hardest and most tricky thing to deal with. Reckon any other job will be childs play in future.

    Thank you again, I wouldn't have had the confidence to attempt this without all the help and advice. πŸ’ͺ😎



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