Results 1 to 15 of 15
  1. #1
    EMS / MedEvac Pilot
    Reputation: Emspilot's Avatar
    Join Date
    Apr 2002
    Posts
    121

    Question High Speed Impact...Replace Carbon Fork..???

    I recently suffered a high speed impact (30mph) with a large (90lb) dog. That's right a dog!!! Anyway, to my total amazement the only thing damaged is my separated shoulder. The front wheel is even true. Now, I have a Look HSC-3 all carbon fork and I can not see any damage what-so-ever. Is the fork safe to ride after such sudden stoppage impact? Will it still have full strength integrity? Again, there is no visible damage at all on the fork.

    Thanks...
    For those who have fought for it,
    life has a flavor the protected will never know.

  2. #2
    RoadBikeReview Member
    Reputation:
    Join Date
    Feb 2004
    Posts
    43

    Carbon Fork

    Carbon is pretty amazing stuff and it will take one hell of a beating. When you get right down to it if you cannot see where their are any cracks in the fiber or any dammage to the fork at all then its probably fine. I would break out a magnifying glass and go over it very cafefully though, espeshially where the forks meet the steerer tube and where the forks go over to metal pieces at the bottom(name alluding me right now). Or you could always take it as an omen that you need a new fork and now is a good time go pick up one

  3. #3
    Domestic Drivin' E-Thug
    Reputation:
    Join Date
    Aug 2002
    Posts
    1,041
    Quote Originally Posted by Emspilot
    I recently suffered a high speed impact (30mph) with a large (90lb) dog. That's right a dog!!! Anyway, to my total amazement the only thing damaged is my separated shoulder. The front wheel is even true. Now, I have a Look HSC-3 all carbon fork and I can not see any damage what-so-ever. Is the fork safe to ride after such sudden stoppage impact? Will it still have full strength integrity? Again, there is no visible damage at all on the fork.

    Thanks...
    Same thing happened to me except when I hit the dog I was only going 23mph. ; ) My fork and front wheel were both fine, but my frame was buckled/totalled and cracked thru during my next race.

  4. #4
    Windrider (Stubborn)
    Reputation: Len J's Avatar
    Join Date
    Jan 2004
    Posts
    21,835

    Cost/Benefit.......

    If it were me....I'd replace the Fork, no other questions asked.


    Why? Because the cost of being wrong is so severe. Can you tell visibly wether the bond between the carbon steerer and the fork has been weakened? What if it fails the next large bump you hit? Carbon can be weakened without visible signs. Let's say now you are going down a fast descent when your fork (which clearly has been severly stressed) decides to break. How severly are you hurt? Now compare this to a $350.00 fork......to me it's a no contest decision.

    I would do the same thing with Light aluminum or carbon bars (and have). It's just not worth the risk of being wrong about potential damage to save a few hundred bucks.

    That's me though.

    I'd replace it My life & health is worth more than a few hundred bucks.

    Len



    "Evil....is the complete lack of Empathy!"

    ""We are what we repeatedly do. Excellence, then, is not an act but a habit. " Aristotle

    No one is as bad as the worst thing they have done & no one is as good as the best thing they have done.........think of that when you feel like you understand someone.

  5. #5
    RoadBikeReview Member
    Reputation: mellowman's Avatar
    Join Date
    Apr 2004
    Posts
    313
    Sorry to hear about these accidents. But guyz, geez...what about the dogs? Seems like the dogs were cushions for your front ends at least feel sorry for them. They live in our world of MAN, have an intelligence of a child and usually get no schooling so they can get confused.

  6. #6
    Cubicle Fugitive
    Reputation: czardonic's Avatar
    Join Date
    Jan 2002
    Posts
    3,079

    There are no guarantees

    First, if nothing else was damaged or knocked out of alignment, can you really assume that the fork was "severely stressed"?

    Second, nobody really knows when a given lightweight aluminum or carbon component is going to fail suddenly due to undiagnosed damage or some flukey confluence of events. You can go crazy and broke trying to eliminate this risk and in the end you'll still be fooling yourself. The next big bump could cause your brand new replacement fork to buckle under you.

    If you don't want risk, ride a steel bike. On a trainer.

    YMMV

  7. #7
    Windrider (Stubborn)
    Reputation: Len J's Avatar
    Join Date
    Jan 2004
    Posts
    21,835

    Good point, but......

    we're not talking about replacing after a minor bump. Rather we are talking about a 23 MPH slam into a 90 lb dog severe enough to cause an accident that broke the riders collarbone. He's worried about the impact enough to ask the question (and he was there). IMO, the doubt is not worth the risk....the penalty for being wrong is not worth it.

    Just my oponion.

    Len



    "Evil....is the complete lack of Empathy!"

    ""We are what we repeatedly do. Excellence, then, is not an act but a habit. " Aristotle

    No one is as bad as the worst thing they have done & no one is as good as the best thing they have done.........think of that when you feel like you understand someone.

  8. #8
    Cubicle Fugitive
    Reputation: czardonic's Avatar
    Join Date
    Jan 2002
    Posts
    3,079
    Since he only asked about the fork, my thought is that he is more concerned about the properties of CF in particular. From my own crash experience, the unknown quantity aspect creates aprehension where you would otherwise say "wheel's fine, must be good to go".

    I severely stressed a CF fork (wheel wasn't fine) and had similar concerns. Since then, I have put enough additional "normal" stress on it such that it could have failed even without the crash if it were so inclined. It still bugs me, but the bottom line is that any CF fork is going to bug me for the same reason, crash or not.

    I was only half kidding about going steel. . .

  9. #9
    RoadBikeReview Member
    Reputation:
    Join Date
    Feb 2004
    Posts
    89

    Are you for real ?

    Quote Originally Posted by mellowman
    Sorry to hear about these accidents. But guyz, geez...what about the dogs? Seems like the dogs were cushions for your front ends at least feel sorry for them. They live in our world of MAN, have an intelligence of a child and usually get no schooling so they can get confused.
    Why don't you ask EMSPILOT how much compassion he feels for the dog...Whose fault was it for leaving the untrained dog to roam free ? It's called personal responsibility, and it extends to more than just yourself, it even extends to your pets (GASP !).

  10. #10
    EMS / MedEvac Pilot
    Reputation: Emspilot's Avatar
    Join Date
    Apr 2002
    Posts
    121
    I appreciate all the input. First off, I have no compassion for the dog. When I can use both my arms again I'm gonna throttle that owner who let his 3 dogs run free. It's a miracle I only hit the one!!

    About the fork, I'm agree with the majority. I'm thinking I should replace it due to the forces involved. Since the wheel is (visibly) undamaged where on the frame might I look for signs of stress/buckling??
    For those who have fought for it,
    life has a flavor the protected will never know.

  11. #11
    The web is a MUT
    Reputation:
    Join Date
    Oct 2003
    Posts
    1,387

    Headset, downtube, top tube, all junctures

    Quote Originally Posted by Emspilot
    Since the wheel is (visibly) undamaged where on the frame might I look for signs of stress/buckling??
    Also check your handlebars over real carefully. Any place that might have absorbed the impact forces, or been impacted in the crash following the impact. If your bike did a flip-flop then give it a total going-over including the chainstays and the deraileurs.

    And note: file a police report and bill the dog owner for the parts. But if the dog died then rethink what I just said as they may counter-sue. Slippery slope and all that. The dog owners are ultimately responsible for the dog, but you are also partly liable in some ways. Just all depends on the circumstances of the accident.

    Bottom line: check your entire bike and all the components over very carefully. Even the pedals and crankarms and chainrings.
    <<a sig line goes here>>

  12. #12
    $4000 bike - two bit legs
    Reputation: PaulCL's Avatar
    Join Date
    Jan 2000
    Posts
    1,438

    Had the same accident

    I hit a 40lb dog at about 35mph. This wreck bent my cromoly fork, killed a wheel, seperated my shoulder. So, I feel your pain.

    IMHO:
    1. Replace the fork. Yeah, $350 is a lot...but you will worry forever. $350 is a lot cheaper than a faceplant in the future
    2. The dogs. I have compassion for the dog that I hit. I wanted to kick the sh*t out of the owner. It ain't the dog....
    3. Take the wheel to your LBS for a once over.
    Paul in Northern Kentucky

    Across the mighty Ohio from Cincinnati:
    The Obesity Capital of the USA
    (Explains a lot of the intolerance about us riders, huh?)

  13. #13
    RoadBikeReview Member
    Reputation: Henry Chinaski's Avatar
    Join Date
    Feb 2004
    Posts
    5,093
    replace the fork

  14. #14
    I don't fear carbs
    Reputation: Bocephus Jones's Avatar
    Join Date
    Feb 2004
    Posts
    2,750
    Quote Originally Posted by Emspilot
    I recently suffered a high speed impact (30mph) with a large (90lb) dog. That's right a dog!!! Anyway, to my total amazement the only thing damaged is my separated shoulder. The front wheel is even true. Now, I have a Look HSC-3 all carbon fork and I can not see any damage what-so-ever. Is the fork safe to ride after such sudden stoppage impact? Will it still have full strength integrity? Again, there is no visible damage at all on the fork.

    Thanks...
    replace. it may be OK, but do you want to take a chance? The medical bills for a fork failure would be much more than a new fork costs.
    Insanity in individuals is something rare - but in groups, parties, nations and epochs, it is the rule.
    Friedrich Nietzsche

  15. #15
    I don't fear carbs
    Reputation: Bocephus Jones's Avatar
    Join Date
    Feb 2004
    Posts
    2,750
    Quote Originally Posted by treebound
    Also check your handlebars over real carefully.
    I'd replace the bars too...they are cheap unless you have some high zoot model.
    Insanity in individuals is something rare - but in groups, parties, nations and epochs, it is the rule.
    Friedrich Nietzsche

Similar Threads

  1. Carbon fiber Aluminum crown fork v.s. all carbon
    By uspsjj9wldcat in forum Components, Wrenching
    Replies: 2
    Last Post: 04-12-2004, 01:39 PM
  2. Another broken carbon fork...
    By TurboTurtle in forum General Cycling Discussion
    Replies: 2
    Last Post: 03-25-2004, 08:48 AM
  3. calling all 1" carbon fork owners
    By Lemondpoprad in forum Cyclocross
    Replies: 2
    Last Post: 03-14-2004, 11:14 AM
  4. ? on Performance Forte carbon fork
    By dirt_diggler_1 in forum Components, Wrenching
    Replies: 1
    Last Post: 03-10-2004, 09:00 AM
  5. mounting caliper on a carbon fork, need help
    By dovid in forum General Cycling Discussion
    Replies: 1
    Last Post: 02-12-2004, 12:33 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  

EUROBIKE

Hot Deals

Latest RoadBike Articles


Latest Videos

RoadbikeReview on Facebook