Durano Plus Failure

[Dogtrousers]

I use Durano Plus tyres. I like them, the mean distance between punctures for me is many, many thousands of km.

But yesterday I had a rear wheel blowout due to the tyre coming away from the bead. (Below left) Closer examination of the tyre shows wear above the bead all round. (below right).

Now, because I pretty much never get punctures I don't often look at my tyres. I just fit and forget. I have a check for tread wear and for embedded flints every now and then but that's it. And this wear isn't visible when the tyre is on the wheel, as you can see just to the right of the split in the left hand picture, it looks OK.

These are 25mm tyres on 15mm Mavic Open Pro rims, so I'm not running the wrong size tyre. (see here)
I pump up to 6 and a bit bars (my pump is graduated in bars) That's about 90 psi. Given that I weigh 92kg and carry a fair bit of stuff with me that might be a bit near the lower limit of the psi range of 85-115. Maybe I'm squashing the tyres too much.
I don't deflate and remove the tyres for regular bead inspection. Well, not until now that is.
The tyre in question has done 5,688.0km (thanks RideWithGPS) It has never had a puncture or been removed in that time. That doesn't seem terribly far for it to wear out completely.
The tyre's front wheel partner of same age is also on Open Pro 15mm and looks OK. I think.

It's not the first time I've split a Durano Plus like this. The previous was a couple of years ago. Same wheel. I've checked the rim for roughness, and not found anything suspicious. Note that the wear occurs on both sides all round the tyre.

So what is caused this, and what have I been doing wrong/not been doing right?

In future I'll be puting a tad more pressure in the rear tyre and checking regularly for bead wear. I think I'm going to stick with D+ though, for their toughness.

 

[Heltor Chasca]

Has the tyre overheated from hot rims perhaps? We’re you descending under load by any chance?

Sharp burl on the rim?

Fascinating.

 

[Racing roadkill]

I use Durano Plus tyres. I like them, the mean distance between punctures for me is many, many thousands of km.

But yesterday I had a rear wheel blowout due to the tyre coming away from the bead. (Below left) Closer examination of the tyre shows wear above the bead all round. (below right).

View attachment 408022

Now, because I pretty much never get punctures I don't often look at my tyres. I just fit and forget. I have a check for tread wear and for embedded flints every now and then but that's it. And this wear isn't visible when the tyre is on the wheel, as you can see just to the right of the split in the left hand picture, it looks OK.

These are 25mm tyres on 15mm Mavic Open Pro rims, so I'm not running the wrong size tyre. (see here)
I pump up to 6 and a bit bars (my pump is graduated in bars) That's about 90 psi. Given that I weigh 92kg and carry a fair bit of stuff with me that might be a bit near the lower limit of the psi range of 85-115. Maybe I'm squashing the tyres too much.
I don't deflate and remove the tyres for regular bead inspection. Well, not until now that is.
The tyre in question has done 5,688.0km (thanks RideWithGPS) It has never had a puncture or been removed in that time. That doesn't seem terribly far for it to wear out completely.
The tyre's front wheel partner of same age is also on Open Pro 15mm and looks OK. I think.

It's not the first time I've split a Durano Plus like this. The previous was a couple of years ago. Same wheel. I've checked the rim for roughness, and not found anything suspicious. Note that the wear occurs on both sides all round the tyre.

So what is caused this, and what have I been doing wrong/not been doing right?

In future I'll be puting a tad more pressure in the rear tyre and checking regularly for bead wear. I think I'm going to stick with D+ though, for their toughness.

There’s little ‘give’ in the sides of the tyres, and they are held in shape more rigidly that some tyres, because of the protection belts. The upshot is, that if you hit anything rough, hard enough ( particularly if banked over ) the tyres ‘tear’ at the bead. It’s too easy to just blat through crappy surfaces, because the tyres are so bombproof, puncture wise. But they do have their limits.

 

[Dogtrousers]

Has the tyre overheated from hot rims perhaps? We’re you descending under load by any chance?

Sharp burl on the rim?

Fascinating.

I hadn't thought about hot rims. I only cycle round Kent and Sussex mostly so I never have to descend any long long alpine style runs where heat could build up. I am fairly heavy handed on the brakes when descending though - I don't like going fast, I'm very aware of my mortality. The brake pads are positioned on the centres of the rims, not at the top.

The wear is all round the tyres on both sides, so won't be down to an individual burl on the rim (not that I could find anything of that nature)_

When it went I was riding on fairly flat terrain. And the loads I carry aren't touring standard, just a rack bag with bit more in the way of tools and food and gubbins than most roadies.

 

[raleighnut]

Brake blocks are set too close to the tyre. DAMHIKT

 

[Dogtrousers]

Brake blocks are set too close to the tyre. DAMHIKT

You know what? I think you're probably right.

I initially thought, "Pah. Don't lecture me about brake block positioning." Then I nipped downstairs and had a look ...

 

[raleighnut]

It 'might' have happened to me 35yrs ago.

 

[smutchin]

Brake blocks are set too close to the tyre. DAMHIKT

That was also my first thought. It might have happened to me once too - after my third puncture just 10km into a 200km audax, I worked out what was causing the problem. Luckily, a fellow rider was able to supply me with a tyre boot and after realigning the brake block I was able to complete the ride with no more grief.

 

[smutchin]

Mudguard stays rubbing is another thing to check for.

 

[raleighnut]

That was also my first thought. It might have happened to me once too - after my third puncture just 10km into a 200km audax, I worked out what was causing the problem. Luckily, a fellow rider was able to supply me with a tyre boot and after realigning the brake block I was able to complete the ride with no more grief.

Dual pivot brakes are the worst for it due to the small arc they move in, new pads are fine but as they wear they need to be lower on the slot and if anyone thinks 'dual pivot' brakes are a new thing they were fitted as standard to my 67 Carlton Clubman,



Weinmann 'Dynamic' calipers

 

[Dogtrousers]

The worst thing is, I actually knew about this. But there's "knowing" and "really knowing".

Someone on a group ride had a very loud explosive blowout right next to me once. The Great and the Good gathered round and diagnosed brake blocks too high. I made a note, and when I fit them I think I do remember this ... maybe. What I didn't know was @raleighnut 's point about the contact point creeping up as they wear.

Every day's a school day.

 

[Ajax Bay]

new pads are fine but as they wear they need to be lower on the slot

What I didn't know was @raleighnut 's point about the contact point creeping up as they wear.

Yes, thank you @raleighnut
Because I'm forcing 28s through blocks which are only 27mm apart, I tend to have to adjust my brake blocks quite often so this has not presented itself for me. But the geometry is there for all to see, if they look.

 

[ChrisEyles]

Yep, I've had this happen to me from poorly positioned brake blocks too. Been super paranoid about fitting new blocks ever since!

 

[Deleted member 1258]

I use Durano Plus tyres. I like them, the mean distance between punctures for me is many, many thousands of km.

But yesterday I had a rear wheel blowout due to the tyre coming away from the bead. (Below left) Closer examination of the tyre shows wear above the bead all round. (below right).

View attachment 408022

Now, because I pretty much never get punctures I don't often look at my tyres. I just fit and forget. I have a check for tread wear and for embedded flints every now and then but that's it. And this wear isn't visible when the tyre is on the wheel, as you can see just to the right of the split in the left hand picture, it looks OK.

These are 25mm tyres on 15mm Mavic Open Pro rims, so I'm not running the wrong size tyre. (see here)
I pump up to 6 and a bit bars (my pump is graduated in bars) That's about 90 psi. Given that I weigh 92kg and carry a fair bit of stuff with me that might be a bit near the lower limit of the psi range of 85-115. Maybe I'm squashing the tyres too much.
I don't deflate and remove the tyres for regular bead inspection. Well, not until now that is.
The tyre in question has done 5,688.0km (thanks RideWithGPS) It has never had a puncture or been removed in that time. That doesn't seem terribly far for it to wear out completely.
The tyre's front wheel partner of same age is also on Open Pro 15mm and looks OK. I think.

It's not the first time I've split a Durano Plus like this. The previous was a couple of years ago. Same wheel. I've checked the rim for roughness, and not found anything suspicious. Note that the wear occurs on both sides all round the tyre.

So what is caused this, and what have I been doing wrong/not been doing right?

In future I'll be puting a tad more pressure in the rear tyre and checking regularly for bead wear. I think I'm going to stick with D+ though, for their toughness.

Brake blocks are set too close to the tyre. DAMHIKT

Brake blocks or a faulty tyre? I use these and I haven't had any problems with them, their puncture resistance is impressive, when I do my weekly check I'll have to have a close look at mine. Many years ago I had a faulty tyre where that had happened, I cant remember the make now, but it made an impressive bang when it failed, woke up the dogs on the farm a hundred yards away.

 

[raleighnut]

Yep, I've had this happen to me from poorly positioned brake blocks too. Been super paranoid about fitting new blocks ever since!

It's not the original fitting that is a problem it is the fact that as they wear the contact area moves away from the hub due to the short arc, V-brakes/Cantilevers do the opposite where as the pads wear they move closer to the hub and can develop that ridge that can make en stick again due to where the pivot is.