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Sidewall cut in brand new tyre

keef66keef66 Posts: 13,123
edited October 2016 in Workshop
Recently fitted a 23mm Pro4 SC to the rear of my CR1 to give a bit more clearance between tyre and chainstays. On it's second outing on Sat morning I found myself on an unexpectedly fast descent (completely new route courtesy of my demented Garmin). Just topped 30mph when the rear tyre went bang!

Once I'd regained control of my heart rate and sphincter, I discovered a neat slice in the sidewall. Closer inspection showed it to be about 2cm on the outside, and 1cm long where the cut goes right through to the inside.

No prospect of getting my wife to rescue me; she was stuck at home waiting for a courier to make a second attempt to deliver something :cry:

After a couple of unsuccessful attempts, I persuaded my biggest patch to stick to the inside of the tyre, and I fashioned a boot from the plastic / card backing from my KMC missing links. This allowed me to fit my spare tube and pump it up to maybe 30 psi, which still had it bulging in a disconcerting fashion, presumably because of the severed threads in the carcass. At which point a passing cyclist stopped to check I was OK (thanks if you're reading this), and pointed out I was less than 2k from a bike shop, Maglia Rosso, if my ghetto fix didn't hold. I was then cursing myself for having no cash or cards with me, at the very least I'd have liked a fortifying coffee and cake. Instead I set off gingerly for home. Remarkably I made it the 20 miles without another blowout or pinch flatting (it felt like I was riding on the rim every time I hit a bump or stray stone)

After briefly wondering if sidewalls can safely be repaired I gave myself a slap, abandoned the idea and ordered a new tyre. And some Park Tool emergency tyre boots. So that's £25 down the drain but a couple of lessons learned.

Take tyre boots / cash / cards
Consider a spare tyre for longer rides
Don't rely on being rescued...

Posts

  • term1teterm1te Posts: 1,462
    I keep 50000 Vietnamese Dong in my saddle bag. Probably worth about 20p, but it is made from a very tough but thin plastic material that is ideal for using as a boot on a badly cut tyre. A bit fiddly, but you can wrap the note around the inner tube and place it under the cut. I only inflated it to about 50psi, but it got me home and the tyre seemed to keep its shape OK.
  • trailflowtrailflow Posts: 1,311
    Recuperate some of the lost money by cutting the old tyre into sections. Then you'll have a lifetime supply of tyre boots. :)
  • keef66keef66 Posts: 13,123
    trailflow wrote:
    Recuperate some of the lost money by cutting the old tyre into sections. Then you'll have a lifetime supply of tyre boots. :)

    I know that's the sensible thing to do, but as a Yorkshireman it's going to be hard taking scissors to a tyre that's only done 38 miles :(

    I'm still cursing the fact that the last pair of worn out GP4S went in the bin; could have usefully cannibalised one of those...
  • cheschcatcheschcat Posts: 95
    Super glue.
  • drlodgedrlodge Posts: 4,825
    I made a couple of tyre boots from an old colgate tube, the thin plastic ones.
    WyndyMilla Massive Attack | Rourke 953 | Condor Italia 531 Pro | Boardman CX Pro | DT Swiss RR440 Tubeless Wheels
    Find me on Strava
  • keef66keef66 Posts: 13,123
    cheschcat wrote:
    Super glue.

    Your faith in super glue is commendable, but I can't see it holding together the sides of a 1cm cut that goes clean through the casing.

    I've read loads about ghetto repairs to sidewalls of MTB tyres, involving super glue, stitching together with dental floss, and patching with car tyre repair kits, but they are usually beefier tyres and run at much lower pressures. Seeing the patched / booted tyre bulging at (probably) 30psi, I doubt I would have any confidence riding a repaired 23mm tyre at 90psi.

    @DRLodge - I have my eye on a nearly empty toothpaste tube, which I'll be adding to my kit to augment the adhesive backed Park Tool emergency boot patches I've ordered with the new tyre...
  • drlodgedrlodge Posts: 4,825
    Those parktools patches are great for big holes, the toothpaste tube patches are good for smaller ones. And if its a very small hole, an inner tube patch should do :-)
    WyndyMilla Massive Attack | Rourke 953 | Condor Italia 531 Pro | Boardman CX Pro | DT Swiss RR440 Tubeless Wheels
    Find me on Strava
  • step83step83 Posts: 4,107
    Gel wrappers are great recuse boots, I had to use one on Saturday with a nice hole from a chunk of glass I failed to see.
  • cheschcatcheschcat Posts: 95
    I'm currently running a GP4000 with 1cm cut in sidewall held together with super glue (glue when deflated) and reinforced with a light tyre boot. Been fine for several hundred miles thus far.
  • keef66keef66 Posts: 13,123
    cheschcat wrote:
    I'm currently running a GP4000 with 1cm cut in sidewall held together with super glue (glue when deflated) and reinforced with a light tyre boot. Been fine for several hundred miles thus far.

    I've got the glue and the tyre boots are in the post, so I may as well give it a go then. Would be good to eke a few more miles out of the bloody thing...
  • cheschcatcheschcat Posts: 95
    I put glue on from both inside and outside (as well as the two facing surfaces of the cut obviously) so there is a thin layer of glue protecting the area around the cut from both sides. For a boot I am using a piece of plasticy cardboard from a swissstop box which seems to be stopping any bulging that might but pressure on the join.
  • sheffsimonsheffsimon Posts: 1,282
    cheschcat wrote:
    I'm currently running a GP4000 with 1cm cut in sidewall held together with super glue (glue when deflated) and reinforced with a light tyre boot. Been fine for several hundred miles thus far.

    Front or rear?
  • keef66keef66 Posts: 13,123
    SheffSimon wrote:
    cheschcat wrote:
    I'm currently running a GP4000 with 1cm cut in sidewall held together with super glue (glue when deflated) and reinforced with a light tyre boot. Been fine for several hundred miles thus far.

    Front or rear?

    If I do try a repair it will be going on the back. I know I can safely come to a halt following a rear blowout on a 30mph descent :D

    I've only experienced slow deflation of a front tyre, and not at speed, but remember how wobbly it made the steering go. Wouldn't fancy my chances of staying upright with a fast front blowout :shock:
  • on-yer-bikeon-yer-bike Posts: 2,974
    I had the same thing with a new Michelin Power Race. Chain Reaction replaced it with a credit note. I would send it back, I definitely wouldnt use it
    Pegoretti
    Colnago
    Cervelo
    Campagnolo
  • keef66keef66 Posts: 13,123
    I had the same thing with a new Michelin Power Race. Chain Reaction replaced it with a credit note. I would send it back, I definitely wouldnt use it

    Seriously?? It's not a manufacturing defect, it's just bad luck; something in the road sliced it open. The cut's longer on the outside (2cm) and only penetrates to the inside for the deepest 1cm in the middle. It definitely wasn't like that for the first 38 miles...
  • on-yer-bikeon-yer-bike Posts: 2,974
    keef66 wrote:
    I had the same thing with a new Michelin Power Race. Chain Reaction replaced it with a credit note. I would send it back, I definitely wouldnt use it

    Seriously?? It's not a manufacturing defect, it's just bad luck; something in the road sliced it open. The cut's longer on the outside (2cm) and only penetrates to the inside for the deepest 1cm in the middle. It definitely wasn't like that for the first 38 miles...
    I dont think something in the road sliced mine open. I think it failed. Ive had 2 PRO 3s do the same thing. I might be wrong, here's a picture what do you think?
    IMG_2073.JPG
    Pegoretti
    Colnago
    Cervelo
    Campagnolo
  • keef66keef66 Posts: 13,123
    Looks like a cut to me; it's sliced clean through the threads in the casing, you can see the cut ends. If it was a weak spot in the casing it would look more frayed I think.

    Fair play to CRC if they did you a credit note...
  • dj58dj58 Posts: 2,184
    keef66 wrote:

    Take tyre boots / cash / cards
    Consider a spare tyre for longer rides
    Don't rely on being rescued...

    Wise words keff66, I do the above, though don't usually take a spare tyre with me, but might do this in future for the times when I can't get a lift back home.
  • on-yer-bikeon-yer-bike Posts: 2,974
    keef66 wrote:
    Looks like a cut to me; it's sliced clean through the threads in the casing, you can see the cut ends. If it was a weak spot in the casing it would look more frayed I think.

    Fair play to CRC if they did you a credit note...

    There were some rough roads on that ride but its hard to imagine anything that sharp. Maybe Ill buy another to go with the front I still have. That is a piece of tyre side wall showing through. Im not sure that would be safe to ride although it did get me home.

    I also had some PRO 4 comps that started cracking and Michelin replaced those along with the inner tubes.
    Pegoretti
    Colnago
    Cervelo
    Campagnolo
  • keef66keef66 Posts: 13,123
    keef66 wrote:
    Looks like a cut to me; it's sliced clean through the threads in the casing, you can see the cut ends. If it was a weak spot in the casing it would look more frayed I think.

    Fair play to CRC if they did you a credit note...

    There were some rough roads on that ride but its hard to imagine anything that sharp. Maybe Ill buy another to go with the front I still have. That is a piece of tyre side wall showing through. Im not sure that would be safe to ride although it did get me home.

    I also had some PRO 4 comps that started cracking and Michelin replaced those along with the inner tubes.

    Round here we get a lot of flint washed onto the roads when it's been raining, and the water helps the little shards slice into the rubber more easily. Wrote off a cheapo Vittoria wire beaded tyre on it's second outing too. No puncture protection, the flint went straight through the centre of the tread, and by the time I'd come to a halt it had shredded the tube beyond repair. Fortunately I found and removed all the fragments in the tyre before fitting the spare tube.

    25mm Conti 4 Seasons on the wet weather bike for that very reason. Punctures very rare with them, and then it's pinch flats from potholes in the dark, or one javelin like thorn through the sidewall.
  • sheffsimonsheffsimon Posts: 1,282
    keef66 wrote:
    I had the same thing with a new Michelin Power Race. Chain Reaction replaced it with a credit note. I would send it back, I definitely wouldnt use it

    Seriously?? It's not a manufacturing defect, it's just bad luck; something in the road sliced it open. The cut's longer on the outside (2cm) and only penetrates to the inside for the deepest 1cm in the middle. It definitely wasn't like that for the first 38 miles...
    I dont think something in the road sliced mine open. I think it failed. Ive had 2 PRO 3s do the same thing. I might be wrong, here's a picture what do you think?
    IMG_2073.JPG

    Looks like a pinch flat to me. I had an almost identical looking cut in a Schwalbe One earlier this year, caused by hitting a pothole at speed.
  • Here's a fix I use.... Take a piece of fine emery cloth rub the inside of the tyre to roughen it up around the cut then take that piece of emery and rub it on itself to remove the abrasive then cut the emery cloth into a shape about twice the size of the cut with smooth rounded corners and feather the edges of your "patch" with a file then apply superglue around the cut on the inside of the tyre over the same area as the patch you have made then add the emery patch abrasive side towards the glue, super glue is awesome stuff when applied to a woven fabric and adheres very strongly to the roughened inside of the tyre
    I've sealed up 1" cuts using this method and never had problems in fact my rear Vredestein senso on my commute bike has covered around 4000 miles with a 1/2" slit repaired this way and it's an almost invisible repair
  • keef66keef66 Posts: 13,123
    Right, that's it, you lot have convinced me to repair the thing. Super glue and emery cloth I have in abundance, and this morning I got my hands (and scissors) on the empty toothpaste tube. Following the Brexit vote I'm tightening my belt. My paternal, Yorkshire family would be proud of me!

    I do virtually all my riding solo and on quiet rural roads, no racing or bunch riding, and it will be on the rear wheel. The bike has no mudguards, so I can easily keep an eye on it. Worst that can happen is it goes pop again, and I'll have a spare tyre with me for that eventuality.
  • keef66keef66 Posts: 13,123
    Aaargh! The front tyre just went the same way. Something put a little slice in the sidewall and the tube went pop. Fortunately going uphill at the time so I came to a halt quickly and safely.

    I booted it with one of my shiny new Park Tool emergency patches and was gratified to see the tyre wasn't bulging at all when fully inflated with a new tube. I may just leave it like that and see if I can wear out the tread before I have to bin it.

    I know it's only a sample of 2 but I'm starting to think that Pro4 SCs aren't up to the flint strewn lanes round here. Never had this with a GP 4 Seasons in 9 years of riding them...
  • svettysvetty Posts: 1,904
    Loads of flints on the roads at the moment, also it's Hawthorn hedge-trimming time round here.......
    FFS! Harden up and grow a pair :D
  • pinnopinno Posts: 42,731
    Super Jackanory Keef, you're not having much luck.

    Funny that pic of the Michelin's. Apart from the 23mm part, is identical to a cut I had in one. Beyond a patch on the inside, which didn't work very well, I didn't try anything else and wish I had now after reading some of the posts 'cos I ended up chucking it.
    I likes my Michelins and rode them for donkeys bar a season on Conti's. Once I was out and descending and there was this odd, thup thup thup thup thup.....tsssssssssssssssssssssssssssss. Oh bollox. Put a tube in after rigorously checking for thorns etc and set off again. Next downhill; thup thup thup thup thup.....tsssssssssssssssssssssssssssss. Double bollox. No more tubes. Had to make 'that' call except the OH doesn't drive and I had to phone a friend (female) to pick me up. Missus wasn't bothered.
    Checked over the tyre again and again and couldn't work out exactly what happened until I noticed the brake pad. The pad had slipped 15 degrees or so and was rubbing on the tyre under braking - only applied the front brake whilst braking for a bend downhill (twice). Wheel was slightly out of true. New Pro 3 too. :oops: I knew I should have bought that T25 Torx sooner.

    On the subject of superglue. There are many types of Cyanoacrylate available very cheap.You can get different setting rates and different viscosities. The slower rate setting one's are less brittle. I have found that repairs using the quick stuff (the Loctite over priced DIY/corner shop stuff most people know of and buy) are a bit brittle for bike usage where there's vibration. Slow set is also very handy for locking threads when you don't want it to go off instantly - overboard cups etc.

    http://www.ebay.co.uk/sch/i.html?_from= ... e&_sacat=0
    seanoconn - gruagach craic!
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