Freehub removal Alexrims

andUK
andUK Posts: 85
edited January 2018 in Workshop
Set of basic Alexrims road wheels: I bought them as new taken from a Chris Hoy bike, I've done about 2000 miles on them.
I'm wanting to service the freehub, as it's become noticeably noisy.
Tried removing the freehub body retaining bolt using an 11mm allen key with an extension bar. This has resulted in the allen key being rounded off, as the retaining bolt is evidently done up very tight and is twelve-sided, meaning that the allen key has less solid purchase than if the bolt were a conventional six-sided one.
I'd be grateful for any "how to free up the retaining bolt" tips.

Comments

  • It's not clear ifyou have rounded the bolt or the allen key?

    In the unlikely latter case, I suggest you get a better quality tool, tools should be made of harder steel than bolts.

    In the former case, you are in trouble and in need of a mechanical workshop
    left the forum March 2023
  • cooldad
    cooldad Posts: 32,599
    That's weird.

    Never seen a double hex on a bike, ever. An Allen key will work, in theory, but always best to use the right tool.

    https://store.snapon.com/Double-Hex-Sta ... 71292.aspx
    I don't do smileys.

    There is no secret ingredient - Kung Fu Panda

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  • Hi, lots of the shimano freehub bolts have that double helix thing. Maybe it gives more space for the qr. if they were standard six-sided then the flats would project too far into the centre. I can see how you get less purchase from a standard Allen key and might round off a cheap set.
    That snap-on tool or similar looks great so I think you might have to get one.
  • Here’s a similar thing. https://www.athleteshop.co.uk/shimano-f ... gL-A_D_BwE
    I did not realise it was called a double helix, thanks for info.
  • cooldad
    cooldad Posts: 32,599
    Hi, lots of the shimano freehub bolts have that double helix thing. Maybe it gives more space for the qr. if they were standard six-sided then the flats would project too far into the centre. I can see how you get less purchase from a standard Allen key and might round off a cheap set.
    That snap-on tool or similar looks great so I think you might have to get one.

    And I did not know that - never actually removed a Shimano freehub. Never had one that seemed to need it.
    I don't do smileys.

    There is no secret ingredient - Kung Fu Panda

    London Calling on Facebook

    Parktools
  • At a guess, the nut internal profile is designed to turn it from an hexagonal shape to a pseudo-round one, better suited to accomodate the axle, which is after all 10 mm, so very tight clearance
    left the forum March 2023
  • veronese68
    veronese68 Posts: 27,294
    Surely it’s double-hex as double-helix is the shape of DNA. Probably the joy of auto correct.
    Back to the OP what sort of noise is the free hub making? Is it just clicking louder when freewheeling? If so it might just be the grease used on installation has thinned and moved around so the pawls are a bit louder. If that is the case I would ignore it for now. If the time comes you have to remove the freehub try to get some penetrating oil in there every evening for a few days before you do the job.
  • andUK
    andUK Posts: 85
    Thank you for the responses, they have been helpful.

    My freehub has become very noisy by comparison to what it used to be when freewheeling. As a personal preference I would like to reduce this noise, which I assume is being caused by the lubrication around the pawls having diminished. I could leave it be, but part of the reason I cycle is that I enjoy maintaining and building my own bikes. Logic tells me that I can take the freehub apart, I just maybe don't have the correct tool/technique and experience for dealing with a very tight retaining bolt that should come undone with an allen key, despite its being a twelve-sided shape.

    I've got a quality set of allen keys, but there is no 11mm with it. So I purchased a Facom 11mm allen key to remove the freehub, given its price of £6, I imagined this would be a proper hardened tool. The problem is that the freehub retaining bolt is very tight, which meant I used an 12" bar on the end of the allen key, which merely resulted in the allen key becoming rounded off. By the latter it is just the very edges (corners) of the allen key flats that have rounded off enough for the allen key to no longer have any purchase within the 12-sided hex of the retaining bolt, I feel the allen key is still good for undoing standard six-sided allen bolts. From that aspect, the double hex tool looks interesting (thank you Cooldad).

    So I will purchase a double hex bit and get some penetrating oil into it prior to removal, and give it another go. Beyond that I will take it to my LBS.
  • jermas
    jermas Posts: 484
    edited January 2018
    If you manage to get the correct size tool, it might be easier to undo (the freehub) if you mount the tool (+/-bar) in a sturdy vice. Place the wheel on the tool and then turn the wheel itself with both hands. This way it keeps the tool from twisting and rounding off. I've undone an exceptionally tight freehub this way- when using a breaker bar didn't work.
  • jermas
    jermas Posts: 484
    One other thing, the tool might be a triple square (xzn), not a double hex. The splines are slightly different angles. I've only used a triple square (xzn) before. If you have the tools, it might be easier to cut the rounded/damaged part off your existing 11mm hex and try again with the vice method above.
  • andUK
    andUK Posts: 85
    Gave up and got my LBS to remove the freehub.

    Degreased, then lubricated the freehub (have used chainsaw oil as an experiment, as it is a thick, sticky oil and others have tried it, seemingly with success).

    The freehub is now nice and quiet when freewheeling and the bearings have been re-greased.

    Thank you for all the above advice.