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Downhill and tires

raymond82raymond82 Posts: 330
edited July 2013 in Road general
How disastrous is it to get a flat with clinchers when going downhill at let's say 65 km/h? Anyone ever experienced that?

During this year's Marmotte I gained quite a lot of confidence in my biking abilities as riding up the Telegraphe and the Galibier I was constantly overtaking people. Of course I started late so I must have been overtaking the slower part of the participants but it was good for the morale. Then during the descent of the Galibier and Lautaret lot's of people (men, women and children) passed as I didn't dare going any faster than 55 km/h or so, mainly cause I was thinking about the results of having a flat.

Posts

  • lawrenceslawrences Posts: 1,011
    It's not going to brutally explode. You can pull over pretty safely.
  • raymond82raymond82 Posts: 330
    My main worry was that the tire will come of the rim after deflating and then I guess most grip is lost. Is that something to worry about?
  • If it worries you that much then you are doing the right thing by going a slow as you feel safe/ comfortable.
    I'm sorry you don't believe in miracles
  • JayKostaJayKosta Posts: 635
    A slow leak probably wouldn't be a problem.
    A blow-out or fast loss of pressure could cause a fall.

    I limit downhill speed so that I can see and react to trouble on the road surface - debris, ruts, cracks, bumps, traffic, etc.

    Saving skin is more important to me than going fast!

    Jay Kosta
    Endwell NY USA
  • ugo.santaluciaugo.santalucia Posts: 26,121
    If you have alloy rims and use tyres which are rated for saying 140 psi and keep them at 100, you will be safe from explosions, while normal punctures will make your tyre lose pressure slowly and you will control it easily. But yes, if you don't feel confident, slow down.
  • raymond82raymond82 Posts: 330
    I guess it makes sense to not go faster than I dare going, it's just that since lot's of people go considerably faster I should be able to do that to. I'm trying to make a distinction between what is really dangerous and what is just fear, so that maybe I can become a little less afraid.
    If you have alloy rims and use tyres which are rated for saying 140 psi and keep them at 100, you will be safe from explosions

    That's good advice, I'll stick to that in the future!
  • keef66keef66 Posts: 13,123
    I on the other hand try to go as fast as possible everywhere I go, especially down hill, so if I do come off it's going to hurt.

    Somehow the thrill of descending overrides the 'what if....' thoughts.

    That said, I do have quite a lot of scar tissue, but most of it as a result of stupid, comedy, slow speed falls
  • sungodsungod Posts: 13,518
    if you are unfortunate enough to flat suddenly (slashed tyre for instance), you try to use just the other wheel to brake as quickly as you safely can, avoid real braking on the flat one unless things ahead are seriously grim, i.e. when decking it is looking better than finding out how long the drop is over the edge :-)

    there're risks in all activities, for cycling you minimise them by keeping the bike properly maintained, checking tyres, brakes etc. before a ride, staying aware and developing handling skills

    if you spend time worrying about what might happen you'll not have much fun, being nervous could even make an accident more likely, relax and enjoy it
    my bike - faster than god's and twice as shiny
  • raymond82raymond82 Posts: 330
    The thrill of going downhill I used to have much more than now, it could be that it had something to do with a couple of bad experiences. I remember ending up next to the road and quite close to considerable depths once when I had old and crappy brake pads. After that (this was during a holiday in the Alps) it just got worse and worse, exactly because I got nervous. The next year I changed to better brake pads and adjusted them properly and it was much better, I just keep thinking of flats but after reading your comments I feel reassured when it comes to that. The final thing is that living in Holland I don't have many opportunities to train going downhill and grow confidence.

    Just now I was looking at tubeless tires, that sounds very appealing to me. I like the technique so maybe I'll convert to that in the future.
  • Stewpot407Stewpot407 Posts: 97
    lawrences wrote:
    It's not going to brutally explode. You can pull over pretty safely.

    Completely irrelevant but.... http://www.youtube.com/watch?v=Ngv7Iu3y1o0
    An aging Trek 5500 OCLV
    Not so aging Pina Dogma (AK61)
  • raymond82raymond82 Posts: 330
    They actually manage quite well, it's hard for me to judge the speed but I guess it's still quite high by the time they hit the floor. Anyway wheel totally rips apart, I don't think that's something I need to fear with aluminum clinchers. Or do you have another video coming?
  • abanazarabanazar Posts: 16
    raymond82 wrote:
    How disastrous is it to get a flat with clinchers when going downhill at let's say 65 km/h? Anyone ever experienced that?

    This very thing happened to me at 41mph descending the County Durham side of the Stang last Saturday. The front tyre instantly deflated with a loud hissing noise. I pulled up without issue, was actually surprised by what a non-event it actually was.

    The bottom line is descend at a speed where YOU feel comfortable.
  • daxplusplusdaxplusplus Posts: 631
    abanazar wrote:
    raymond82 wrote:
    How disastrous is it to get a flat with clinchers when going downhill at let's say 65 km/h? Anyone ever experienced that?

    This very thing happened to me at 41mph descending the County Durham side of the Stang last Saturday. The front tyre instantly deflated with a loud hissing noise. I pulled up without issue, was actually surprised by what a non-event it actually was.

    The bottom line is descend at a speed where YOU feel comfortable.

    Ditto - For me it was at the bottom of Leckhampton Hill, Cheltenham .. my front deflated too .. I don't know how fast I was going at the time but my usual speed is between 40-50mph.

    I think the key thing is not to panic. Just let the bike do it's thing and no sudden changes of direction.

    But really it was a non event .. I was more annoyed that I had a puncture to fix.
    Sometimes you're the hammer, sometimes you're the nail

    strava profile
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