Is it bent?

Discussion in 'Australia and New Zealand' started by eddiec, Jan 5, 2005.

  1. eddiec

    eddiec New Member

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    No, not a thread about recumbents...

    Was enjoying a lovely commute this morning (first since Christmas), and zipping down High St Sth to Barkers Rd in kew, when a passenger of a car up ahead decided to join me on this fine day and open the door wide into the bike lane... Thank God for nature strips with thick couch grass as that's where I landed after slamming into it...

    Now nothing seems overly broken physically (couple of scars and numb fingers on the right hand which I'm hoping will pass) and the bike survived ok, but on the rest of the ride it felt somewhat wafty and drifty, especially at the front. Now, this could just be my shock-addled brain, and nothing looks skew, but are there some obvious possibilities and quick checks to see if the frame's been bunged out at all or such? Wheel seems true, frame looks ok, headset seems tight. Not sure what else it could be if anything...


    Guess I'll be riding that stretch slower and more cautiously from now on - Pity it has to be that way. :(
     
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  2. suzyj

    suzyj New Member

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    eddiec wrote:

    > Now, this could just be my shock-addled brain, and nothing looks
    > skew, but are there some obvious possibilities and quick checks to
    > see if the frame's been bunged out at all or such? Wheel seems true,
    > frame looks ok, headset seems tight. Not sure what else it could be
    > if anything...

    Sorry to hear about your prang, but good to hear you're generally okay.

    Really light steering is often a sign that the head-tube angle has increased. This is very common in prangs where you run into something with the front wheel.

    The best way to check for such damage is to put a straight-edge under the downtube, up near where it joins the head tube, and check for ripples in the tube. Any light showing between the straight-edge and the tube means the tube has been damaged. Do the same for the underside of the top-tube, again near where it joins the head-tube.

    If you know what the head angle was before the crash, it can also be useful to measure it directly using a protractor.

    If in doubt, take it to a reputable bike shop or frame builder, who will be able to check it out, and send the bill to the twit with the door.

    Regards,

    Suzy
     
  3. eddiec

    eddiec New Member

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    Thanks for that. Have checked it over and it looks fine - No ripples, no flaking paint, no nothing. I'm suspecting it was probably just the normally light steering combined with a bit of cross-wind and my pain/shocked induced paranoia. Amazing how tough these devices are sometimes!

    On the bright side, the twit with the door will at least be up for the cost of a very nice bike - Don't you love how door prangs end up buckling two panels :) The new Nissan X-Trail - now with optional non-closing door!
     
  4. mfhor

    mfhor New Member

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    Heh heh heh

    Glad you're (almost) alright.

    Good advice from suzyj, as usual.

    When you're better, try riding no hands on a quiet road. If it wants to go left or right repeatedly, run a string from the head tube to each rear dropout. Measure the distance (accurately) to the seat tube from where the string goes past it. If it's different, you have acquired some frame twist/bend. Again, a frame builder is required, unless you have a very heavy vice/bench and a great big steel bar (crowbars work) and some shims to pack the headtube and BB shell (kids, be careful when trying this at home).

    I did that once (it did it to me?) to a late model Merc passenger door when they opened it across a bike lane whilst stuck in traffic. Bike was OK, I was a bit bruised, but the inside of the door was a mess, shreds of Connolly (?sp) leather hanging off the lining, not closeable et c. The woman was very apologetic, I was late for work, so I left her trying to close her door, and yelling at her teenage son for almost killing a cyclist.

    M "blackberries are softer than boulders" H
     
  5. Grip

    Grip New Member

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    Eddie, all good advice from above. Also take notice of whether or not the bike wants to "tip" into turns one way more than the other... perfect example of a rear triangle out of line.

    You're obviously not far from us... if you feel inclined, drop in with the bike and we can run our frame alignment tool over it in about 3 minutes. No charge. Glad you're OK.
     
  6. hippy

    hippy Guest

    "suzyj" <[email protected]
    > The best way to check for such damage is to put a straight-edge under
    > the downtube, up near where it joins the head tube, and check for
    > ripples in the tube. Any light showing between the straight-edge and
    > the tube means the tube has been damaged. Do the same for the
    > underside of the top-tube, again near where it joins the head-tube.


    I really hope the curve in the Pug's downtube
    is supposed to be there!

    hippy
     
  7. Ok. I've definitely been hanging out with the scuba group too much; my
    first reaction on seeing the subject was to think of decompression
    sickness. :)

    Glad to hear you're ok, even if your bike might be a little worse for
    wear.

    --
    My Usenet From: address now expires after two weeks. If you email me, and
    the mail bounces, try changing the bit before the "@" to "usenet".
     
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