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Speed wobble = crash!

AdamskiiAdamskii Posts: 267
edited August 2008 in The bottom bracket
I suffered at the fate of the dreaded speed wobble at the weekend.

I was decending on a 17% single track road in Wales at 45mph when it began. I'm a pretty experinced cyclist and I have read up about how to combat speed wobble if it ever was to occur but when it actually happens to you it's a different story.

I tried holding the top tub between my knees, releasing both brakes, only using my back break but nothing worked and it got progressively worse until the road curved round the the left I couldn't stear and went straight on into a ditch at 40mph!

I managed to total trash my nice hand built wheels and break my helmet in half. Spent most of the afternoon in hospital, nothing broken (luckly) but I do feel like I've been dropped from a great height.

A big thanks to the motorist who took me to hospital.

Be careful out there folks!!!
It's all good.

Posts

  • robbarkerrobbarker Posts: 1,367
    edited August 2008
    Ouch! glad you're in one piece. I had a horrible one of these decending Cader Idris at about 50mph once. I managed to recover it but it was very, very scary.
  • biondinobiondino Posts: 5,990
    I don't understand why you're descending a 17% hill at 45mph. How on earth could you hope to stop if necessary even without the wobble?

    Sorry, will stop being your dad. Glad you're okay.
  • boybikerboybiker Posts: 531
    Anything over 40 scares the censored out of me anyway.
    The gear changing, helmet wearing fule.
    FCN :- -1
    Given up waiting for Fast as Fupp to start stalking me
  • NuggsNuggs Posts: 1,804
    boybiker wrote:
    Anything over 40 scares the censored out of me anyway.
    I've discovered that 34's my limit after having had my wheels skip sideways while sprinting after a car (I was trying to keep up with a couple of old dears barely doing 30 in an NSL area). That was definitely squeaky bum time... :shock:
  • fossyantfossyant Posts: 2,549
    I got speed wobble at about 50 coming off Woodhead a few months back due to cross winds.....managed to drop it to 40ish and was fine, before letting the speed creep up once the wind was behind.

    If you get it near a bend, you is going off.
  • CorianderCoriander Posts: 1,326
    Ooooooooooooh, what's speed wobble? It doesn't sound good.

    Am glad I didn't know about it going down a hill at 42mph the other day. :shock:
  • boybikerboybiker Posts: 531
    edited August 2008
    Speed wobble is basically a speed induced instability in the bike which happens at a speed which is determined by your bike geometry. its basically where the bike starts to become unstable due to the coupling between the bike the rider and the road and it can mean that the bike is uncontrollable. In theory it can be stopped by simply letting go of everything so the rider isn't as tightly coupled to the bike and it breaks the feedback loop, in practice when it happens and you are doing 40+ downhill and you suddenly cannot steer letting go of everything is virtually impossible.
    it motorbiking its called a death wobble or a tank slapper because the handlebars swing so wildly that they hit the fuel tank.
    The gear changing, helmet wearing fule.
    FCN :- -1
    Given up waiting for Fast as Fupp to start stalking me
  • DoobzDoobz Posts: 2,800
    hey Adamskii, sorry to hear this mate.. Where was the Descent? I hope you recover and you are insured for your loss.. Main thing is your still alive to tell the tale :)

    Adios
    cartoon.jpg
  • AdamskiiAdamskii Posts: 267
    I was going south at Llanymawddwy in the Snowdonia national park. There are some seriously steep hills round there. The speed came very quickly and by the time I thought hey I'm going to quickly it was to late.

    I'm not quite sure what insurance I could claim on but I pick up a new winter bike tomorrow so I'll probably leave it now until the spring.
    It's all good.
  • Rob SallnowRob Sallnow Posts: 6,279
    boybiker wrote:
    it motorbiking its called a death wobble or a tank slapper because the handlebars swing so wildly that they hit the fuel tank.

    Indeed they do!!! :shock:

    http://www.youtube.com/watch?v=b_D84j8z ... re=related
    I'd rather walk than use Shimano
  • Red RockRed Rock Posts: 517
    Sorry to hear about your off, but glad you're not seriously hurt.

    Red Rock
  • Captain FagorCaptain Fagor Posts: 1,768
    boybiker wrote:
    it motorbiking its called a death wobble or a tank slapper because the handlebars swing so wildly that they hit the fuel tank.

    Indeed they do!!! :shock:

    http://www.youtube.com/watch?v=b_D84j8z ... re=related

    I'm glad that's a Eurosport clip, as presumably the bloke was okay. That's one scary bit of footage.
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