Metzler Z6 Failure

[ncroadtoad]

Out for a quick spin today and I noticed the rear end of my 07ST feeling a little light. Thought maybe it was the interstate truck traffic affecting the top box - it happens. About 5 minutes later, no question, a flat rear tire.

Getting it to the shoulder I find it is indeed flat - very flat. So, struggling it up onto the center stand, I can find no foreign object in the tire. But while looking, I push lightly on the center of the tread and it caves in like a flat basketball. Odd? Anyway, I put about 20lbs of air in and look again. Sure enough, a small (1/8") cut just off center of the middle of the tire. I plug it, fill the tire, it holds and all of a sudden these bulges start appearing on the tire. First, right next to the plug, then on the other side and eventually all around.:censored

Called MoTow and now she sits in the garage, waiting for new shoes.

Belt separation maybe? It's a new one to me. The tire was a Metzler Z6 with about 6,000 miles on it. Thought ya'll might be interested.

Oh yea, I checked the pressures before I left this AM and I had 42 rear and 40 front.

 

[lugnutz]

I have used Metzlers for years on many different bikes and have never seen anything like that. I can tell you that I worked in a tire store and have seen the same thing on many a car tire. What happens when the tire goes flat the side wall is pinched between the rim and the road and it causes small tears or rips that allow air in and creates the bubbles, also riding even a short distance on a flat tire can damage the belt. You might be seeing a combination of both. I am not ruling out any kind of tire defect but they are not common on motorcycle tires.

 

[punk rocka]

Whatever it is, it's ugly and scary! Glad you are OK!

 

[ncroadtoad]

I too have used Metzlers for a long time - off and on. No complaints about the brand. The tire might have been low for a few miles before I felt it. Don't know, I just have never seen this on a motorcycle tire - and I've flattened a few...

 

[ncroadtoad]

Whatever it is, it's ugly and scary! Glad you are OK!

It is ugly isn't it. It's so shameful to see your ST on a tow truck....

 

[Two Brothers]

Is that the plug thats close to the bubble? If so what has happened is that the steel belts were broken when the puncture happened. This lets air in between the rubber and the steel belts, bubble occurs. This is why you do not plug a tire.

We have seen this in bias and radial tires.

 

[George]

Agree it's separation. I've had that happen but only after many miles on a low tire. How many miles on this ride? Wouldn't expect that to happen over a short distance.

I, too, have run Metzlers with no problems in the past. I'd pass this one back to the Metzler rep for evaluation.

 

[ncroadtoad]

Is that the plug thats close to the bubble? If so what has happened is that the steel belts were broken when the puncture happened. This lets air in between the rubber and the steel belts, bubble occurs. This is why you do not plug a tire.

We have seen this in bias and radial tires.

Yes, the plug was within an inch of the original bubble. Of course it wasn't there when I plugged. It (bubbling) then spread gradually throughout the tire. I do agree with you 100% about not plugging a tire. But, that said, I personally would not keep and ride on one, but plugging to get me home or to a place where I can replace the tire - in a heartbeat. That is unless it looks like this one..

Thanks for the thoughts on the air seepage. I haven't seen it before.

 

[ncroadtoad]

Agree it's separation. I've had that happen but only after many miles on a low tire. How many miles on this ride? Wouldn't expect that to happen over a short distance.

The flat occurred about 30 miles into the ride. I felt the first signs of getting loose about 25 miles into it. The temp was 40 and pressures were spot on when I departed.

 

[Two Brothers]

The flat occurred about 30 miles into the ride. I felt the first signs of getting loose about 25 miles into it. The temp was 40 and pressures were spot on when I departed.

More than likely once it started going down it started getting hot. That caused the braek down. How hot was the tire when you stopped?

 

[Dinkie Diesel]

By the time you got'er to the shoulder had it been bumping along for a few feet completely flat? The wheel rolling over the flat tire and buckling it more than likely ruined it's integrity.

 

[Two Brothers]

Had a Goldwing rear blow on while it was on the lift. Same thing, I pumped it up to get it on the lift and it blew just as I stepped by it. Pretty load and lots of force on my lower legs.

 

[ncroadtoad]

More than likely once it started going down it started getting hot. That caused the braek down. How hot was the tire when you stopped?

Real hot... The smell was strong.

 

[Two Brothers]

Real hot... The smell was strong.

The best explaination is that the tire cooks itself. This will cause the rubber to come apart from the belts.

 

[dond]

I know Mellow remembers the high failure rate of the OEM Dunlops on the Valks. They were delaminating.

The MEZ4 had lots of problems too

 

[Silver Bullet]

++ on what Two Brothers is saying ,riding on a low tire puts a lot of heat on the side walls and the rim is trying to cut through the tire from all the weight and hence the destroyed tire ,seen it happen on many a car tire . Just seems the right reason for the damage IMHO ! Just glad you did not get hurt or go down !

MIKE

 

[ncroadtoad]

Well Metzeler's are off and Pilot Road 2's are on. I appreciate all the comments, I agree that it is most likely that the tire cooked while running low. I should have checked it as soon as I thought it felt a little odd.

The inside of the Z6 looked normal, nothing to indicate the ugliness on the outside. As to the Z6's in general, I've alternated between the Metzeler Z6's and Avon Storms over the past 100k miles. This is the first issue I've had with them and it was on a 85% worn out tire that I ran too long on low pressure. Just thought I'd give the PR2's a spin..