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No, that's not phonetic
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Discussion Starter · #1 ·
Over the course of about 75 yards my front tire went from normal Stanned Kinetic tire>Stans hematoma>Stans aneurism>Stans IED.

Thank Dog I wasn't blazing down the trail. I woulda gotten killed...



 

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No, that's not phonetic
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Discussion Starter · #3 ·
The tire does have some miles on it, but it had just been stanned for the first time about two weeks prior.

We had just finished up a ride and were on the road heading back to the cars. I suddenly noticed that something was stuck to my front tire. It looked like a flat glob of tar or something. It started getting bigger and bigger with each revolution. I did not realize at that point that I was getting one of those Stans/Kenda delamination bubbles forming and still had it stuck in my head that it was a blob of someting I picked up off the road. After a few more tire revolutions the bulge got big enough to jam in the fork arch, it popped like a huge zit, and it blew white sh!t all over me and my bike.

The flap of rubber tread was still in tact, and the threads under it were still in good shape. The two just decided to separate spectacularly. On my next ride I got a pinch flat in another Kinetic that stans refused to seal. I am still pretty skeptical of the crap. I would not use stans again without running UST or DH tires in any case. Luckily I don't have to put up with it at home where we never flat and just run tubes. Road-tripping to the desert is a somewhat different matter though.
 

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Oh Man! Can't believe my eyes. My friend is switching from Kenda's for that very reason. Well, his tire didn't look like a missle smashed into it. He has had similar problems though! Good luck!
 

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Photog Cyclist.
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That tire was thrashed----Might have had some structural defect/damage prior to Stan's. I only use Stan's on new tires some of which are Kenda tire haven't had a problem yet.
 

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Kenda Nevegals have been exploding even when not using stans. I think if there is a
weekness in the construction stans could speed up the process. I have run stans in three wheelsets. 1 set of Wtb Motoraptors 1 set of Tioga Red Phoenix, 1 set of Tioga
Factory Extreme XC tires. I have had no problems with tires exploding and no flats for a year. This Kenda and Stans thing seems to be true problem. I am trying to convince my brother not to change to Nevegals because of the stans compatability problem. I wish it were consitant though. I read of people using the Nevegal and stans for the life of the
tire with no problems. I am glad you were not injured this kind of failure could have been
painful.
 

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tscheezy said:
The tire does have some miles on it, but it had just been stanned for the first time about two weeks prior.

We had just finished up a ride and were on the road heading back to the cars. I suddenly noticed that something was stuck to my front tire. It looked like a flat glob of tar or something. It started getting bigger and bigger with each revolution. I did not realize at that point that I was getting one of those Stans/Kenda delamination bubbles forming and still had it stuck in my head that it was a blob of someting I picked up off the road. After a few more tire revolutions the bulge got big enough to jam in the fork arch, it popped like a huge zit, and it blew white sh!t all over me and my bike.

The flap of rubber tread was still in tact, and the threads under it were still in good shape. The two just decided to separate spectacularly. On my next ride I got a pinch flat in another Kinetic that stans refused to seal. I am still pretty skeptical of the crap. I would not use stans again without running UST or DH tires in any case. Luckily I don't have to put up with it at home where we never flat and just run tubes. Road-tripping to the desert is a somewhat different matter though.
understand.. I had great experience with Schwalbe tires with the eclipse strip and stan's sealant... but as in your case, I don't have that many punctures around here, so I eventually got tired of dealing with the white goop and went back to tubes...
 

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NoTubes.com
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Nice pics tscheezy. But it is a mechanical failure of the tire and not something caused by sealant. The blister (hematoma/aneurism) comes from delamination of the layers within the tire casing. The same delaminations occur with tubes installed but it is possible that with a tube, it may not have blown out as dramatically. Don't think going to UST tires makes the problem go away either, they experience the same issues.

Tire takes an impact or multiple impacts and layers separate within the tire. If running tubeless, air can get in between the layers. With sealant present it often seals the "blister" but taking further impacts will continue to move the air around and enlarge the blister until failure. The same mechanism at work that allows tires to shed knobs. The problem is more prevalent at higher pressures (casing takes a more solid impact) and on tires with larger knobs as they provide leverage between the contact patch and casing.

It is a rather tricky process in the tire industry (not just bicycles) to make the rubber layers of the tire stick to the nylon casing and when it's not perfect, delamination occurs.
 

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Thanks MikeB- very very interesting. My friend has had all of the knob shedding, blistering troubles with his beloved Kenda's that you have mentioned.

Would there seem to be a recurring problem with the manufacturing process itself? Compounds used? Can sealant (in any way) be responsible for the delamination process? The reason I ask, in all my years of riding, I have had only one tire ever blister. Dropping knobs? I consider a knob or two falling off to be "normal" wear and tear.
 

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No, that's not phonetic
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Discussion Starter · #13 ·
Mike B. said:
If running tubeless, air can get in between the layers.
I think this is the crux of the matter. I don't doubt that with time and use tire casings will get mechanically degraded. It just seems that with tubeless you will experience catastrophic failures that would never reveal themselves if you had been running tubes because with the air confined inside a tube the pressure is not getting through the threads and pushing solely on the outermost rubber of the tread.

To be fair, we started out with 4 stanned wheels running Kenda tires: two 2.6 Kinetic Stick-e's, a 2.35 Kinetic Stick-e, and a 2.35 Nevegal Stick-e, and only two of those did not deal with stans well. The front 2.6 Kinetic exploded. That made me extremely nervous and I put a stanned Tioga Factory DH 2.3 on instead. With a lot more rubber inside the tire, I expect that one to hold up. I figured teh other Kendas were ticking time bombs also, so I actually carried another 2.3 Nevegal in my pack the next few rides. After getting a pinch in the rear 2.6 Kinetic that the stans juice showed no interest in sealing, I put in a tube and then after the ride swapped tires around and stanned a Maxxis Minion 3C 2.5 DH tire. That I also expect to hold up, again due to all the rubber inside the casing. Despite starting with 2 1/2 scoops, a lot of the stans juice in the Kinetics had already evaporated in just 2 weeks. This is a function of the thin and porous sidewalls, I figure. The Kinetics have served me very well on a number of trips to the desert, but they are just too wimpy to withstand the extra stresses that running tubeless puts on them. I will just stick to DH tires if I want to run tubeless in the future. I am purely after cacti protection here. I see no weight benefit (in fact, the opposite since I can't make it without DH tires apparently...) or reduction in rolling resistance, personally.

Barny ran the 2.35 Nevegal and the 2.35 Kinetic the whole trip with no flats or aneurisms. She is a lot lighter than me and is not as hard on equipment.
 

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I "think" that I read something about Kenda tires being incompatible with the sealant because of some chemical reason. Because Kenda uses a certain substance for their carcasses. Don´t remember what it was exactly. But there´s something like this I think.

Greetings Znarf
 

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I've been using true tubeless tires since 2001 and never experienced such a failure. that tire was useless at the start but I think maybe even a new tire of the wrong construction and the wrong hit could do the same
 

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flow where ever you go
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I'm with you

23mjm said:
That tire was thrashed----Might have had some structural defect/damage prior to Stan's. I only use Stan's on new tires some of which are Kenda tire haven't had a problem yet.
only new tires and no problems yet with karmas (or Conti Protection tires for that matter). On my third set of Karmas.
 

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SS Pusher Man
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Znarf said:
I "think" that I read something about Kenda tires being incompatible with the sealant because of some chemical reason. Because Kenda uses a certain substance for their carcasses. Don´t remember what it was exactly. But there´s something like this I think.

Greetings Znarf
You mean this?

"ATTENTION KENDA VALUED CUSTOMERS
KENDA DOES NOT ENDORSE THE USE OF ANY FLUID BASED SEALANT PRODUCTS IN KENDA TUBE TYPE OR TUBELESS TYPE TIRES. USE OF ANY FLUID BASED PRODUCT IN KENDA TIRES WILL BE AT YOUR OWN RISK AND WILL VOID ANY WARRANTY CLAIMS.

THANK YOU!
Kenda Management"
 

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NoTubes.com
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Not to pick on you Znarf since it seems to be a common misconception, you may have read it somewhere but it's just not true. Kenda's position on sealant is based on the fact that they do not wish to test every sealant on the market and don't know what Joe Mountainbiker might be making in his garage and therefore choose to say "no sealant." At one time, sealant was listed on their website as an approved method for fixing UST punctures.
 

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Hum, that's something to think about Tscheezy. I've been running Nevagals/BlueGrooves for 2 years with Stans and I absolutely love it so I don't think I could convince myself to go back to tubes. However your experience is something to reflect upon. Judging by the looks of your tire it seems like it had quite a bit of mileage on it. So I think I will now apply the following theory to my use of Stan in regular tires. I will now make sure I change my front tires as soon as they have some kind of damage on it or once a year. Hopefully this will help mitigate the risk and at the same time it will give me a solid reason to get new tires more often! :D
 
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