Bloody Puncture...question

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Bloody Puncture...question

Postby DoubleSpeeded » Fri Aug 09, 2013 9:36 pm

. Continental City Tyres on my MTB... (simillar to this one) Image

First time got a puncture by glass...
found that the shrapnel had cut a small slit and wedged into the tyre but was easily pulled out (the glass was approx. no more than 5mm)... made a pinhole in the tube.

im very happy with these tyres... and i think they are discontinued.

ive put a new tube in and rode home..


would it be recommended i still continue to use the same tyres.. or is it something that would eventually wear open from that point.

its a non-folding tyre by the way.
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by BNA » Fri Aug 09, 2013 9:51 pm

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Re: Bloody Puncture...question

Postby il padrone » Fri Aug 09, 2013 9:51 pm

Keep using the tyre, you should have no further problems. If the tyre, when pumped up, shows a noticable cut you may want to put a patch on the tyre from the inside, or others have suggested using shoegoo.
Riding bikes in traffic - what seems dangerous is usually safe; what seems safe is often more dangerous.
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Re: Bloody Puncture...question

Postby Duck! » Fri Aug 09, 2013 10:23 pm

Depends really how big the hole in the inner surface of the tyre is. If the hole in the tube is only a "pinhole", then it's likely the exit hole in the casing isn't much bigger, in which case the tyre will be fine to keep using. It's only if the hole is big enough to allow the tube to bulge through that you need to worry about it.
I had a thought, but it got run over as it crossed my mind.
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Re: Bloody Puncture...question

Postby DoubleSpeeded » Sat Aug 10, 2013 10:32 am

Duck! wrote:Depends really how big the hole in the inner surface of the tyre is. If the hole in the tube is only a "pinhole", then it's likely the exit hole in the casing isn't much bigger, in which case the tyre will be fine to keep using. It's only if the hole is big enough to allow the tube to bulge through that you need to worry about it.


right, like where the tyre would start to seep out.

hmm thanks guys for replying

its always painful rear wheel tyre changes.

also, what pressures are people running for that ssort of tyre.

i think they generally recommend about 55 - 60psi... so i tend to get it to 60 at the max since its not an Off-Road Tyre...
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Re: Bloody Puncture...question

Postby il padrone » Sat Aug 10, 2013 11:22 am

Frank Berto recommends having a 15% tyre drop (under the rider's weight). Not an easy thing to measure, however he has come up with a graph that shows the relevant tyre pressures to give a 15% drop, for different tyre widths and different wheel loads (note: the wheel load is for just one wheel ie. your weight will be split 60:40 between rear and front)

Image

A wothwhile article on tyre pressures and riding is this one by Jan Heine

As a side effect, the suspension loss tests confirmed once again that higher pressures don’t make the bike faster even on very smooth pavement. And this time, we tested with a power meter instead of a roll-down test. So we had confirmed the results with two different methodologies.
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Re: Bloody Puncture...question

Postby DoubleSpeeded » Sun Aug 11, 2013 9:42 am

il padrone wrote:Frank Berto recommends having a 15% tyre drop (under the rider's weight). Not an easy thing to measure, however he has come up with a graph that shows the relevant tyre pressures to give a 15% drop, for different tyre widths and different wheel loads (note: the wheel load is for just one wheel ie. your weight will be split 60:40 between rear and front)

Image

A wothwhile article on tyre pressures and riding is this one by Jan Heine

As a side effect, the suspension loss tests confirmed once again that higher pressures don’t make the bike faster even on very smooth pavement. And this time, we tested with a power meter instead of a roll-down test. So we had confirmed the results with two different methodologies.



hmmm

im about 82KG

and the tyre.. ive forgotten how much mm is the thickness

its definately thicker than 37mm...

not on the chart?
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Re: Bloody Puncture...question

Postby FuzzyDropbear » Tue Aug 13, 2013 9:49 am

Not sure if this helps, I run between 45 and 55 psi on my City Contacts. 45 when I'm riding through the bush on the way home on Friday and then pumped back up to 50-55 on the weekend for the usual commute on the black stuff. I'm approx 85kg or so.

Bugger to hear about your puncture, I had one of those in mine about 30km after I put them on. Now they've gone over 4,300km and still going strong, no need to buy another :D

Cheers.
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Re: Bloody Puncture...question

Postby Bah77 » Tue Aug 13, 2013 11:47 am

I got a similar puncture, pinhole through the tyre, seemed ok, changed the tube, 1000km later and the hole had made itself bigger and repunctured the tube.

Knowing that, next time i would at least use a tyre boot, or duct tape and old tube where the glass poked through.
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Re: Bloody Puncture...question

Postby DoubleSpeeded » Tue Aug 13, 2013 12:41 pm

Bah77 wrote:I got a similar puncture, pinhole through the tyre, seemed ok, changed the tube, 1000km later and the hole had made itself bigger and repunctured the tube.

Knowing that, next time i would at least use a tyre boot, or duct tape and old tube where the glass poked through.


Well what brand tyre was it?

And what type, Kevlar folding or wirebead?
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Re: Bloody Puncture...question

Postby Bah77 » Tue Aug 13, 2013 12:50 pm

Some giant branded one (700x23) that came with my bike, so nothing special.
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Re: Bloody Puncture...question

Postby Duck! » Tue Aug 13, 2013 1:48 pm

Bah77 wrote:Some giant branded one (700x23) that came with my bike, so nothing special.

AKA Kenda, which range from pretty ordinary to fairly reasonable.

DoubleSpeeded wrote:And what type, Kevlar folding or wirebead?

Doesn't matter, bead construction is not related to puncture resistance.
I had a thought, but it got run over as it crossed my mind.
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Re: Bloody Puncture...question

Postby Dragster1 » Wed Aug 14, 2013 10:28 pm

DoubleSpeeded wrote:
Bah77 wrote:I got a similar puncture, pinhole through the tyre, seemed ok, changed the tube, 1000km later and the hole had made itself bigger and repunctured the tube.

Knowing that, next time i would at least use a tyre boot, or duct tape and old tube where the glass poked through.


Well what brand tyre was it?

And what type, Kevlar folding or wirebead?

Did you mean Kevlar belts. I have wire bead tyres with Kevlar belts for puncture protection http://www.maxxis.com/Bicycle/Hybrid/Overdrive.aspx
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