Marzocchi 20mm thru-bolt question

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  • Marzocchi 20mm thru-bolt question
  • DiscJockey

    I keep reading how there’s a ratchet built into Marzocchi’s thru-bolts, but just want this clarified.

    I have a 2009 fork with 20mm thru-bolt. At the bottom of the LHS leg are 3 ‘teeth’ that protrude from the 20mm hole. The thru-bolt has a sprung part that hooks onto these teeth.

    I seem to have 2 problems:

    1) With thru-bolt really tight (I mean if I tighten the lever with my foot) it’s pointing forwards at the 3 o’clock position

    2) I can loosen the bolt just by turning the lever anti-clockwise – I don’t have to push the sprung notch at the other end to disengage it from the teeth.

    Is the ‘ratchet’ mechanism that people refer to simply the ‘teeth’ and notched part on the LHS of the thru-bolt ?

    Can I choose which position the lever sits in when fully tightened ?

    The axle has the ratchet internally. Turn the handle until it clicks. This requires a crap load of force! The toothed bit you can see doesn’t have anything to do with it.

    Sounds like you’re not tightening it enough tbh.


    I’m tightening it by standing on the lever, to the point where I’m worried it’s going to snap. An when I tighten it like this, I then have to use a mallet to undo it again. That can’t be right. There’s definitely nothing clicking inside the lever itself….

    Edit: I’m assuming this is a 2006 66? IIRC the 888 has a bolt-up clamps?

    Serious question: how strong are you?

    The axle works a bit like a torque wrench.

    You should be able to tighten the lever until the point where the internal spring lets go, and the lever snaps round by 120 degrees. When it does that ‘snap’ you know its tight enough.

    1) you’re sticking a helluva pressure on the lever at this point
    2) watch out
    3) its a bit lethal

    TBH I could never fathom the point of that sprung tooth thing, it does absolutely nothing when the axle is tightened up properly.

    There is (or should be) an o-ring on the axle – greasing that will help.

    The force to ratchet it does feel disproportionately high, but it does ratchet around (assuming it’s the same QR axle I had)


    It’s a 2009 55. I’ll try greasing the o-ring, and pushing harder 😉

    I agree that the spring/notch thingie on the LHS seems a bit pointless. The manual states that you have to push the little hooked arm in with your finger before you can unwide the lever, hence I assumed that was the ratchet being referred to. On mine, you just unwind the lever and the sprung arm just pops itself in round the teeth on the fork leg – pointless?

    Yeah that’s what mine does.

    My guess is its some kind of US based legally mandated idiot proofing.


    Just tried again, this time with grease, but no difference, even with some hefty thwacks from my Thor hammer….

    I know people are saying you’ve got to turn it really hard, but this is getting ridiculous now – if I punctured out on the trail, I’d never get this undone again it’s so tight.

    I guess it’s possible that the internal ratchet could have failed ? Sounds unlikely though….

    Just to be sure, I have the following, which might be specific to 55s:

    Premier Icon jonathan

    I had some 55ATAs where the axle was just like that. I knew in theory that it should click round, but it never did. I think I did manage to loosen it enough to click by undoing the bolt on the end, then clicked it round until the lever was pointing where I wanted it and did it back up again.

    Never worried about tightening it until it clicked – don’t think it ever worked properly. If it’s good hand tight then it’s tight enough.


    Thanks Jonathan – you got my hopes up there…but just tried that with a 3mm allen key and the bolt just turns independently to the main 20mm axle and lever 🙁

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