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I was taking off my front wheel and realized that the actual fork sits directly onto the threaded part of the axle.

Wouldn't this ruin the threads?

enter image description here

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    Actually looking at this picture closely, it looks as if the thread is damaged a bit, that shiny part to the right looks flat? – stijn Jun 21 at 17:41
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That's how it should sit, yes. There is no significant force applied on the threads themselves, the wheel is held in place by the friction forces between locknuts and dropouts. Here are a couple of quotes from Sheldon Brown's website:

From this page:

If the skewer is properly tightened, the axle is held in place by the friction of the locknuts' being pressed against the inside of the dropouts. If this were not the case, horizontal dropouts would not be usable, since the forward pull on the chain creates a larger force against the axle than supporting the rider's weight does.

From this page:

In practice, the axle can be quite a bit shorter than this...even 1-2 mm protrusion past the lock nuts will suffice to locate the axle properly, so, when converting a hub to the next wider spacing, it is usually unnecessary to replace the axle.

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  • Thanks. Also found a video that fits the fork directly on the axle threads and also explains that the washer is meant to keep it in place if it becomes loose. youtube.com/watch?v=3dvQBweaHHU – Luca Matteis Jun 21 at 10:43
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    Some nuance: in my experience the 'no significant force' bit is only true for road use. For ountain biking or anything which includes jumping that is no longer always the case. Unless tightened extremely hard the quick release cannot develop enough friction to keep the wheel in place in the presence of such forces and as such it's pretty common to have the axle threads bite into the fork or frame, sometimes to the point they won't take bolts no more. Which doesn't matter at all because that part of the axle doesn't ever see a bolt, it's designed like that because that's just the easiest. – stijn Jun 21 at 11:25
  • Ah I see!! It's just the tip of the threaded axle that sees the bolt! Thanks :) – Luca Matteis Jun 21 at 12:16
  • @stijn if you're thinking of a QR setup like this, how would you service the bearings if the axle threads got chewed up? – Chris H Jun 21 at 16:19
  • @ChrisH if you're lucky the axle is of harder material than the fork and/or the thread isn't damaged, or not enough that you cannot get the nuts of anymore. Otherwise: not much left to do than using sheer force to get everything off, ripping threads apart even more, then replacing axle and nuts. – stijn Jun 21 at 17:35

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