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Thread: Safe Speed?

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    Safe Speed?

    I have recently got a speedo, and going down a local fire trail/dirt road I found that I have been getting 88km/h. Is this safe on a XC bike (in terms of stresses on the frame)?

    Cheers

  2. #2
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    Let me put it this way

    I'd do a lot of testing at lower speeds before I did that. Lots of different things can happen, and very quickly, at that speed. It is all good until it's not.

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    Not saying it is or isnt, but thats exactly why I dont run a speedometer on my bars. I'd look down and see I was going well over 50mph and instantly slow myself down out of fear. Not good for race times. So I mounted it on my seatpost, right under/behind my saddle. Still get all the post ride stats, without the speed induced fear

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    sh..t, at that speed you'll just knock a tree over and keep riding through thinking did i just hit something.

    We hit 90km/h (well when i was younger) all the time on our roadies so i'd say as long as you inspect the bike regularly, keep her well maintained and are confident enough to do it, plus ensure that the track is the same as it was last time you rode it (no extra washoutsetc) then why not.

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    Cheers guys

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    I'd be more worried about the effects on other people of riding a bicycle with a Speedo.
    Attached Thumbnails Attached Thumbnails Safe Speed?-speedo-rider.jpg  

    I'm a member of NSMBA and IMBA Canada

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    Quote Originally Posted by Geoff Gumper
    I have recently got a speedo, and going down a local fire trail/dirt road I found that I have been getting 88km/h. Is this safe on a XC bike (in terms of stresses on the frame)?

    Cheers
    I'd work on calibrating your speedo. Maybe you have it set to a 29er wheel size and you're on 26's. There's no way you're really hitting 56mph offroad on a XC bike. If you are... then no it's not safe. At that speed, a small rock could cause your bike to disintegrate. 56 MPH is tough to hit on a road bike going down a huge hill. It would be suicide on a MTB while off road.

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    Quote Originally Posted by jd1072
    I'd work on calibrating your speedo. Maybe you have it set to a 29er wheel size and you're on 26's. There's no way you're really hitting 56mph offroad on a XC bike. If you are... then no it's not safe. At that speed, a small rock could cause your bike to disintegrate. 56 MPH is tough to hit on a road bike going down a huge hill. It would be suicide on a MTB while off road.
    +1!!!!

    56mph on a mountain bike is flying! I hit 50+ on my roadie, but it takes effort and concentration. Pretty sure I couldn't even get close to that on the knobbies!

  9. #9
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    A short vid of me cruising the fire road a couple years ago..
    Honestly... ahh I give up

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    Quote Originally Posted by jd1072
    I'd work on calibrating your speedo. Maybe you have it set to a 29er wheel size and you're on 26's. There's no way you're really hitting 56mph offroad on a XC bike. If you are... then no it's not safe. At that speed, a small rock could cause your bike to disintegrate. 56 MPH is tough to hit on a road bike going down a huge hill. It would be suicide on a MTB while off road.

    No not buying that we bomb down fire roads at 60 +kph no problem... and no a small rock does not cause the bike to disintgrate...

    What does happen is gravel is thrown up into the down tube and leaves dents...I got a big rock chip on my pedal too.

    Buddy has a big rock chip in his shin, he was following me a little too closely.

    I have hit 95 kph on pavement with slicks on a MTB, again no problems very stable....

    Will it hurt when you crash oh yeah.

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    Quote Originally Posted by highdelll
    A short vid of me cruising the fire road a couple years ago..
    It's funny that the guy went to such great lengths but then used a helmet that popped off the second something went wrong...you'd think they'd have worked that out better.

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    Quote Originally Posted by muddytire
    It's funny that the guy went to such great lengths but then used a helmet that popped off the second something went wrong...you'd think they'd have worked that out better.
    yeah, I fired him...
    he said 'strap-ons' were gay
    Honestly... ahh I give up

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    I'd also suggest the calibration is off. The absolute fastest I've ever gotten my mountain bike to go was 50 even, and that was down one steep paved road.
    I'm pretty comfortable with speed in the dirt though....
    Addicted to the dirt......with no hope for recovery.

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    Quote Originally Posted by Broke That
    I'd also suggest the calibration is off. The absolute fastest I've ever gotten my mountain bike to go was 50 even, and that was down one steep paved road.
    I'm pretty comfortable with speed in the dirt though....
    uhhh...dude...I can't read the words in your post because I can't quit looking at your avatar.

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    Quote Originally Posted by muddytire
    uhhh...dude...I can't read the words in your post because I can't quit looking at your avatar.
    You are not the first to have this problem.
    You are now, officially certified as "non Gay".
    Addicted to the dirt......with no hope for recovery.

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    asdkjh fsjh fhsdj sdlhf hjlsdfie ldsfhlh fsh sdflhe ehlsnnsle sdflehflf
    .
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    sorry, brain frozen, avatar taken control uuuurrrrrr

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