• 09-16-2012
    Trees138
    LOUD ping or pop from fork/head tube area when strong force is applied.
    I hit a small barrier/divider cycling home on Friday, it knocked me over, but the front wheel was fine, the rear was bent up, but I assumed that was from me landing on it. I was able to ride it home the remaining 5 miles.

    After swapping out the wheels I noticed a loud ping when I would brake (disc brakes) heavily in the front. I thought it may be the front rotor (I couldn't remember for sure if I'd torqued the rotors on), so I swapped the other front wheel back on. I had the same loud ping/pop when stopping with a decent amount of force. I then decided to see if it wasn't brake related and noticed that when I compress the fork by hopping on it I would get the noise as well. I didn't test it a whole lot because I like my front teeth and didn't know how close to a complete failure I was or wasn't. But needless to say it isn't a brake issue.

    I waited until daylight and pulled apart my fork/headset/frame and inspected. I also checked the main triangle for any noticeable cracks, but have found none. I pinned the tire against a wall and compressed the fork as much as I could and heard nothing, but this doesn't mean the fork is ok,

    I inspected the headset, it appears fine. The only thing I see that appears to be damage is to my headtube. It appears the metal has deformed as evidenced by cracking of the paint on the backside of the lower bearing area, as well as some "gouging" or perhaps deflection of the material on the inside. I'm highly doubting bikesdirect would be willing to help me out here, if I can isolate it to this I may just buy a Razzo to get me through. I can see how this would make a loud ping as it would allow the race to deflect back under heavy load.

    The real question is how can I verify that my fork is good? My biggest concern is that the steerer could have been damaged, and sadly the fork is more expensive than the frame.

    Anyone ever experience this before? Does anyone know of a way to checkout my fork? It seems solid, but I find it hard to apply the kind of force we're talking about here.

    Would yo condemn the frame with the kind of damage we're looking at or am I jumping the gun here?

    I'm eager to get my bike back to a safe and rideable condition. Also, the bike is a Gravity 29point5.

    Pictures.... resized to 1280 width, I apologize if that is too large.

  • 09-16-2012
    Trees138
    Upon further inspection it had occurred to me that I shouldn't be able to take the bottom bearing cup out with my fingers....

    When I place it back it you can see a noticeable deformation of the bottom of the HT.

  • 09-16-2012
    mimi1885
    That's a massive pic:)
    Check your disc brake mounting and bolt it could be the bolt hitting the rotor, or the edge of the rotor hitting the inner top of the caliper when load applies.
  • 09-16-2012
    dru
    The pinging could be your HS bearings. They are no longer in the same plane so they will have a hot spot of very high loading.

    Drew
  • 09-16-2012
    Trees138
    mimi, I do not believe this to be a brake issue as I can produce the noise with using the brakes.

    Drew, I agree. Allowing the HS to move back probably puts it under more stress, even though it isn't much.

    I've e-mailed BD, but I think I may just buy the Razzo.