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impossible front sprocket nut removal!

Discussion in 'Technical and Troubleshooting Torque' started by Androo, Apr 10, 2005.

  1. I need some magic tricks on how to remove an impossible front sprocket nut.. :roll:

    the bike is a 1997 yzf600r with 36000kms, the offending front sprocket isnt the stock one. the bike engine was only luke-warm at the time. WD40 was applied prior to the attempt.

    with some maticulous help from Lordtb (I highly recommend him for any work you need done!), the rear sprocket and chain were not a problem, but the front sprocket wouldnt budge.

    we ended up trying a suitable size socket into something like a 1/4 inch bar (the weak point), going into a 2m brass pole. also a bar through the rear wheel instead of using the rear brake. with quite a lot of force, the small bar ended up bending but not the slightest move from the bolt :?
  2. A quick prayer to the gods of the angle grinder?
    Probably not the best idea quite yet but desperate times call for desperate measures.
  3. i'd prefer to avoid the angle grinder :( :(
  4. It's not a left hand thread is it?

    Maybe you could go down to your nearest tyre store and get em to hit it with the rattle gun?
  5. Worst comes to worst, visit Bunnings and purchase an impact driver, just make sure that it has a 1/2 inch drive to take a socket. Easy to use, just need a hammer and the correct socket. Invaluable tool.

  6. well I'll be damned.. I have one of those :D .. always wondered what I would use it for but there ya go! I'll give it a go some time soon (not sure if I've got a big enough socket here)
  7. Hiya Androo.. isn't it always the last bloody bolt! :evil:

    Coupla things. did you loosen each bolt in turn before removing? always best to do that, as sometimes removing bolts causes more load on others, and teh problem you have.

    if possible to do without "colaterall damage" get a hammer and give the offending bolt a good hit squarely on its head. that will often loosen them up.

  8. (corrected my original post to say "nut" rather then "bolt" .. oops - it's just one large nut holding the front sprocket on)

    we did try a bit of shock torture on it, but it didnt seem to help :(
  9. bugger, makes it harder.

    You could try heat (lpg gas torch), followed by "percussive persuasion"

    The impact wrench will help, but make sure you use proper impact sockets, normal sockets don't last long when used with impact wrenches.
    If you can borrow a "torque multiplier" then that's the best option, local garage/workshop should have one.
    Otherwise keep soaking in wd40/rp7/crc or similar.

    Last resort, cold chisel the nut of the bolt, hit the chisel at an angle towards anticlockwise, it should come off but will (obviously) need replacing.

    An old VW beetle my old man owned had a seized back left hand brake drum nut, the drum was held on by a big (26 mm iirc) nut, we tried heat, wd40, impact etc, no good.
    We ended up clamping, tying and bolting the ring spanner to a ladder, placing the spanner/ladder on the ground behind the beetle and reversing, the beetle was just about to bend the ladder, and lifted the back left wheel when it suddenly let go!

    sometimes persitance is the only answer. Glood luck!!

  10. FFS DONT !! use any heat unless you want to replace the output sharft seal !

    Use the impact socket, just make sure your trying to undo it the right direction and it's not a left hand thread. if it's not budging , stop and take it to a bloody dealer!

  11. Who will use heat, followed by impact to remove it.

    trust me, if the nut is that siezed, it way be the only way. Yes you may damage the seal, but the buggers got to be removed.

    You don't need a great amount of heat to crack the "seal" between nut and shaft.
    I was a "practising" mechanic for 19 years, and am still qualified.
    As a series of last resorts, after all the more civilised methods have failed, you will resort to heat, then cold chisel, that's why every workshop has these tools.

    But do double check it's nut a left hand thread, and if nervous about how much force to use, then yeah, take it to a workshop and let them take the risks, and your money.
  12. hmm I cant imagine why it would be seized, since it's not the stock sprocket so is only a few years old.

    did try turning it both ways to try and help it loosen up or if it happened to be a left hand thread - though it shouldnt be, otherwise the force of the engine would be loosening it.

    guess I'll give it a few more goes with WD40 and then try the shock driver
  13. And im not either ?

    My advise not to use heat and stuff his seal up, was bc at the moment his bike is still rideable to get to a workshop etc.

    But if a 'novice' No insult there Androo ! :)
    was to pour the heat in and stuff things right up he would then have the extra expense of getting his bike towed to a workshop, and find that a rattle gun would probably have done the job in seconds anyway, now have a minor hicup turn into a major headache.

    Sure try to help guys out if they get stuck doing what should be simple and easy maintanance work, but sometimes too much information can overwhelm and get them to try things that are beyond there capabilitys and do more harm than good.

    I've had too many bikes bought into me in boxes, where the advice the customer got was beyond him and went way too far ending up costing an arm and a leg to

    A: put back together
    B: then diagnose the original problem ( if not apparent durring reassembly)
    C: 6 hrs labour for a job that would have taken myself or another mechanic a max 1/2 hr to do
  14. stuck nut???
    a few methods....

    1) use a nut splitter..hire them from a tool shop
    the only downside is..you need a new nut
    but they ALWAYS work!

    use a rattle gun..i have one and have never had a problem getting a sprocket (or any other nut) undone!

    use an impact socket..get 'em from your hardware or tool store
    whack 'em on and then use a 4lb Engineers hammer (NO stuffing around here) hit the f##ker , it will loosen the nut

    use a long bar....like a 700mm or 900mm long ½" drive bar
    get them from repco or Bursons or your tool store
    you can use them to get anything off

    5) the hot 'smoter or gas axe
    heat the nut a bit (not red hot) by concentrating the heat on a corner of the hex of the nut (not the bolt shaft etc)
    This will loosen the nut


  15. Good advise VTR bob, a rattle gun would be a good tool in this case.

    I was an army mechanic, used to not having all available tools and a bunch of irrate gunners/grunts/truckies/engineers/whatever all screaming for vehicles or equipment. Rattle guns were not usually available in the scrub, or my backyard shed (is on the list of must haves tho :wink: ) But gas torches were always around (quick way of brewing up in a short halt :) )

    Rarely damaged a seal using moderate heat and some persuasion, but your right, I tend to assume that readers are in the situations I was in, and wrongly assume the equipment is military strength.

    I stand corrected, and defer to your current status as opposed to my ex status as a greaser.

  16. i had probs myself i couldnt get it off iether and in the end stuffed up my speedo.
    but thats alright i ride my bike with one thing less to worry about
  17. reply

    If you cannot get to a bike shop with a good rattle gun, try a tyre shop.
    They usually have a huge array of sockets and the best ratle guns.

    Son has Honda 450 chook chaser and had the same prob. I bent a 7' crow bar and the mogrel did not budge. Lifted the bike off the ground with two people on it.
    Shop gave it two squirts with the gun and it was off. The bike was only a month old so nut should not have been rusted/frozen.

    hen you put the nut back, remember to put a good waterproof grease on the thread first. Will save headaches next time.


  18. no offence taken :) but dont worry, I'm not one to take risks with expensive things (I'm looking forward checking my valve clearances soon :D)

    I didnt know you were a mechanic bob.. do you have a shop?
  19. Yeah im a mechanic , but gave the 'dirtyhands' game away a few years ago.
    I'll tinker now and again but even i take my pride and joy to a bike shop now, manly bc i have better things to do with my time, and havn't the $$$ to kit myself out with all the right gear needed for todays high tech machines .

    In fact i've got a box in the garage a tools i'll never use again to donate to Dr Mike at OCD racing in Oakleigh, i'd rather see em used than just rusting away, things like vacume gauges etc , im keeping all my "basic' hand tools so i can still play and do the occasional mod to my bike and oil changes and so on.

    But im always here to help a biker in trouble ( in fact got a few bikes going over the phone when they've broken down when out in the hills )


  20. Rattle Gun will have it off in a few seconds.... Best thing I've got in the garage for loosening stuff like that. Impact driver would be the next best thing.