Punctures

Teach
Teach Posts: 386
edited April 2011 in Road beginners
I know there have been various threads on here, but a couple of questions.
I cycled the Lakeland loop and loved it apart from 2 punctures, both of which happened on the descents from Hardknott and Wrynose.
I have Mavic Aksium Race wheels. These are fairly new. I can't say I had checked the the rim tape before the race, but when I put new tubes in there didn't appear to be anything wrong with them.
I had a flat on the front and then on the next hill I had a flat on the rear.
The tyres were originally pumped between 105/110.
The flats appeared at the back of a spoke. There was a hole in the rim tape and a matching hole in the tube.
The tape on the front one appeared to have shrunk as though it had been heated. The rims were very warm from braking.
Did I do something wrong? I know some of you will say I braked too much, but sorry I wanted to live. Did I have too much air in? Do I put a double rim tape in there ?
Was I just unlucky?
Did the front not get a flat the second time, because there was probably less air in it?
Final question, if I was to mend the puncture now, are patched tyres safe to use?
Having a puncture on a hair pin bend isn't much fun!

Comments

  • desweller
    desweller Posts: 5,175
    Sounds like the tape is too narrow to me. It won't shrink under heating (not if it's any good, anyway).
    - - - - - - - - - -
    On Strava.{/url}
  • balthazar
    balthazar Posts: 1,565
    I concur: Good tape rim tape won't be affected by rim heating, you weren't braking too much, and well-repaired tubes are fine.

    Velox cloth tape is commonly available and won't cause this. I find it irritating for other reasons – but I use it anyway, because I can get it anywhere. Get the right width for your rims.

    Rim heat from braking has real consequences, but I don't think there are any hills in the UK long enough to cause them. Down Alpine switchbacks (or equivalent) extended braking might cause the inflation pressure to rise enough that the tyre blows off the rim. The solution is to reduce the pressure pre-emptively. I've never heard of that happen here, even on tandems which are loaded doubly.
  • danowat
    danowat Posts: 2,877
    DesWeller wrote:
    Sounds like the tape is too narrow to me. It won't shrink under heating (not if it's any good, anyway).

    I had this problem with a new set of Easton wheels, rim tape was too narrow.
  • Teach
    Teach Posts: 386
    Thanks for your comments. The rim tape is going to be changed, but I'm not convinced it was too small. You can see where a hole has blown through the tape and into the tube. The hole is over the end of a spoke. It's the same on both wheels. :?
  • desweller
    desweller Posts: 5,175
    It's the other way round. The tape supports the tube against the holes in the rim. If the tape yields or moves to one side of the hole, the tube is unsupported so will expand into the hole and fail.
    - - - - - - - - - -
    On Strava.{/url}
  • cougie
    cougie Posts: 22,512
    I'd just run two loops of insulation tape round in the rim
    Cheap and effective.
  • Bobbinogs
    Bobbinogs Posts: 4,841
    edited April 2011
    if I was to mend the puncture now, are patched tyres safe to use?

    I always mend my tubes if they are reasonably fixable (I don't bother with snake bites or anything too big) and haven't had a problem. I use a decent puncture kit (well, actually one that was a freebie) when I get back at home and just make sure that something presses on the patch until the glue has fully cured.

    There was a thread on here a while ago about fixing tubes and it was probably 50/50 with some throwing and some fixing. I couldn't see any definitive evidence for throwing (if using in the UK); it just seemed to be a "can't be bothered" option which is fair enough but not for me. Funny really, I can justify spending £400 on some nice wheels but won't spend £3.50 on a tube unless I have to.
  • Thebigbee
    Thebigbee Posts: 570
    Last few punctures I have had I repaired them with a puncture repair kit from the pound shop and worked just fine.

    Am looking into getting into proper road riding and would prefer not to have to repair a puncture if I am 30 miles from home, on the side of the road. Or carry the tools and spares.

    I just want to be able to go and ride without the pain of carrying a backpack.

    Takes me long enough to repair / change a tyre or tube when I am at home with all equipment to hand!

    Puncture "proof" tyres are a good investment IMO.

    I have previously used Specialized Armadillo, Schwalbe marathon plus racers and Michelin Tracker - I think and never had a puncture on them.

Categories