PROBLEMS WITH DUNLOP RACE TIRE

[HOTROD_316]

  I have been running DUNLOP race tires since 2002, and have not had any trouble out of them until last year at the GNF. The tires are coming apart on me, and I don't understand why.  Dunlop replaced my rear tire that split at the GNF last year with no questions asked.  Since then, a friend of mine who runs Dunlop tires began having the same problem.  The rear tire was coming apart.  The Dunlop representative said that it was okay to run the tire with the 2 in. split because he said it was only cosmetic.  He said he would not replace it. I continued to run the tire, DUMB ON MY PART, and mounted a new set for a practice at Roebling Road.  These tires split too, as you see in the picture. I called Dunlop and told them the tire was splitting, and they told me to calm down and not to use big words like "splitting" and "coming apart". You can be the judge on what you call it, I call it splitting and coming apart! I told them I would meet them in Daytona, and show them the tire. I took the defective tire to the Dunlop trailer.  They only wanted to replace the rear tire. I asked them to give me a SET of the same tires because you should never mismatch tires. I would have been satisfied with a new set or a refund for the set, but they refused.  It is unprofessional of such a well-established company to not back their product.  I ended up having to miss 2 sessions of my track day, and the 1st practice session at Daytona because tech would not pass my bike with the defective Dunlop tire.  Because Dunlop refuses to help a long time paying customer, there is only one other option.  That option is to show everyone who runs Dunlop 208 GPA tires to watch out for this defect.  I know that I am not the only one that is having this problem. I have now switched to a new brand of tires, and I am satisfied.  If you don't trust your tires then you should stay home and save your money.

[jigmoore]

i'm not a tire guy...but i am a quality manager in a die casting plant, so i understand quality problems in a mfg environment...

i also think there are some similarities between the die casting process and the tire making process.

i strongly agree with you that this appears to be a serious problem.  got a couple comments:
- don't let anyone tell you that 'there musta just been a bad batch....here's a new tire for ya'.  a motorcycle tire would be considered a safety critical item which would mean that extraordinary measures are taken in the mfg process to ensure that no bad ones are made.  i would expect less than 5 tires per million would be defective.
- my experience is that the tire guy at the track don't know chit.  call dunlop, speak to brubaker or whoever is in charge now, and find out how to know where this tire was made.  call the mfg plant and ask to speak to the quality mgr.  don't be an alarmist with him, just try to hand him the facts.  he's the main guy that can prevent this from happening.
- realize that, in my opinion, they owe you nothing more than a replacement tire.  woulda, shoulda, coulda....someone made a mistake.  they don't owe you the world.  your motivation should be to prevent others from getting hurt.
- don't give up the tire unless the person receiving it assures you that you will get an answer on what was wrong with it.

good luck.

[Team-G]

The Dunlop representative said that it was okay to run the tire with the 2 in. split because he said it was only cosmetic.   I called Dunlop and told them the tire was splitting, and they told me to calm down and not to use big words like "splitting" and "coming apart".

Well, the tire IS coming apart.  Specifically, the tread layer.  What you see there is the tread seam separating.  (Tires are built in several layers)  When the tread is wrapped around the carcass it has a cross seam that should adhere (via stitching) and basically disolve  during the curing (vulcanization) process.  If any of the rubber compounding, green product, build, stitching, & curing processes are wrong, that's what you can end up with; as well as running tires at incorrect (either too high or low) pressures.  All of these are even more critical with high speed rated tires.

IMHO, they owe you a new rear.

[jigmoore]

and if they made one bad one....they made many more.

[Team-G]

and if they made one bad one....they made many more.

Yup.  If I was a factory guy, I'd be checking the tire ID code and run the stats on a few thousand before-and-after builds.

[TommyG]

That`s scary....real scary!!! :o

[Mark Bernard]

I had the same exact problem last year. I have been running the Dunlops since 99. After "every tire I got form Dunlop" last season split after one session. I even had one split in the rain. Just had the tire replaced and in 5 laps on a semi wet track it split. I have dumped dunlop for Perilli's. I should have done that a long time ago. I really like the Perilli tires. Dunlop lost my business for good in the beginning of last season. I have enough to worry about. I Dont need tire issues. . . and now I dont. Dunlop really screwed them selfs last year and its not any better this season from what I have heard. "Dunlop sucks... Perilli rules! IMHO!
Bernie!

[HOTROD_316]

i'm not a tire guy...but i am a quality manager in a die casting plant, so i understand quality problems in a mfg environment...

i also think there are some similarities between the die casting process and the tire making process.

i strongly agree with you that this appears to be a serious problem.  got a couple comments:
- don't let anyone tell you that 'there musta just been a bad batch....here's a new tire for ya'.  a motorcycle tire would be considered a safety critical item which would mean that extraordinary measures are taken in the mfg process to ensure that no bad ones are made.  i would expect less than 5 tires per million would be defective.
- my experience is that the tire guy at the track don't know chit.  call dunlop, speak to brubaker or whoever is in charge now, and find out how to know where this tire was made.  call the mfg plant and ask to speak to the quality mgr.  don't be an alarmist with him, just try to hand him the facts.  he's the main guy that can prevent this from happening.
- realize that, in my opinion, they owe you nothing more than a replacement tire.  woulda, shoulda, coulda....someone made a mistake.  they don't owe you the world.  your motivation should be to prevent others from getting hurt.
- don't give up the tire unless the person receiving it assures you that you will get an answer on what was wrong with it.

good luck.

I agree they don't owe me the world but all I asked for was a set of tire to replace the set I purchased. If you bought a car and 5 hours later the engine blow up would want a new car or you money back or just fix the engine? Enough is Enough. If you check the WERA board you will see that this becoming a common problem around our racing circut. Thanks for the advice I will look into it.

[Fat_Nate]

What bikes are you riding?

Anyone having these problems on SVs?

[HOTROD_316]

What bikes are you riding?

Anyone having these problems on SVs?

I am riding a 05 GSXR 600. I don't know if anyone is having the same problem on the SV's but alot of people are having the same problem around the race circut. Check the wera board. Thanks

[Super Dave]

I race and ride on Michelins.

However, over the course of years and years of doing this, I have raced on quite few Dunlop tires, among others.

This is something that happens to some Dunlop tires on the race track.  It never affected the performance, and it never self destructed.  It is common.

[HOTROD_316]

I race and ride on Michelins.

However, over the course of years and years of doing this, I have raced on quite few Dunlop tires, among others.

This is something that happens to some Dunlop tires on the race track.  It never affected the performance, and it never self destructed.  It is common.

So you would ride the tire for a race ?