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Racing Discussion => Racing Discussion => Topic started by: G 97 on July 01, 2003, 08:16:26 AM

Title: Dunlap 208 GP separation question
Post by: G 97 on July 01, 2003, 08:16:26 AM
Recently I have experienced or witnessed several sets of Dunlop 208 GP tires in the 180/120 size experience separation at the tread seam where the tire tread is combined.  It looks as if someone took a razor blade and cut the tire at a 45% angle from side to side all the way across the tire about a half inch deep.  The build dates are 1801 1901.  This has happened mostly with rears but a few fronts as well.  I have also had a few delaminate as well as having what looks to be air bubbles in the rubber compound.   Anyone else.  
Title: Re: Dunlap 208 GP separation question
Post by: oldguy on July 01, 2003, 08:43:30 AM
Did it look like this?

(https://www.ccsforum.com/proxy.php?request=http%3A%2F%2Fwww.layke.com%2Ffiles%2FD208GP.jpg&hash=7ca9b978398f82f3d92b0939387c9a80e7d169b9)
Title: Re: Dunlap 208 GP separation question
Post by: pmoravek on July 01, 2003, 08:45:02 AM
Check with a guy named Mat Mladin.
I'm sure he'll have an opinion about dunlops.
(Couldn't happen to a nicer guy IMHO)
 ;D
Title: Re: Dunlap 208 GP separation question
Post by: G 97 on July 01, 2003, 08:54:28 AM
Doug, that is it.  In some cases it goes all the way across and deep too.  When talking to Dunlop they become rather coy and act as if they have no idea to what I am trying to describe to them.  
Title: Re: Dunlap 208 GP separation question
Post by: tigerblade on July 01, 2003, 09:17:39 AM
The only 208GP I tried ended up looking like the one in oldguy's pic.  We had a thread about this on here a while ago.  The Dunlop guys pass it off as normal and harmless.
Title: Re: Dunlap 208 GP separation question
Post by: SliderPhoto on July 01, 2003, 09:26:26 AM
QuoteRecently I have experienced or witnessed several sets of Dunlop 208 GP tires in the 180/120 size experience separation at the tread seam where the tire tread is combined.  It looks as if someone took a razor blade and cut the tire at a 45% angle from side to side all the way across the tire about a half inch deep.  The build dates are 1801 1901.  This has happened mostly with rears but a few fronts as well.  I have also had a few delaminate as well as having what looks to be air bubbles in the rubber compound.   Anyone else.  

Hey Garth, I had that same thing at Brainerd last year.
Title: Re: Dunlap 208 GP separation question
Post by: MightyDuc Racing on July 01, 2003, 09:35:30 AM
All I have run this year is 208's, and I have yet to have that problem (knock on wood).  There is a big thread either on here or the WERA board about it.  Go to the WERA board and search it.
Title: Re: Dunlap 208 GP separation question
Post by: Thingy on July 01, 2003, 10:38:07 AM
Knuppy had that happen on a set of slicks this year out at Pikes Peak.  I think it was on a 16 1/2 inch rear.  I took it up to the dunlop boys and he said that it was where they join the tread and not to worry about it.

I am not sure if he was blowing me off or was telling the truth.  Either way, we ran it another day and had no problems.
Title: Re: Dunlap 208 GP separation question
Post by: oldguy on July 01, 2003, 01:39:44 PM
I wasn't too impressed so I backed off a couple of seconds and then had Pirellis put on at the end of the day.
The tire guy can say "Don't worry about it" all he wants, but it's my butt riding 140+ on that tire not his.
Title: Re: Dunlop 208 GP separation question
Post by: xlr8tn on July 01, 2003, 04:04:14 PM
i bought 2 rear's of last year's model and had it happen to one of mine.  the dunlop guy called over a fellow racer and he said "oh...happens all the time...nothing to worry about".  Dunlop guy says..."nothing to worry about".  I came back later after practice and it was worse and said i didn't feel comfortable racing on this and insisted he change it.  He stated, "i'll do it once, but if the other does it, your on your own".  Thankfully, the next one was fine.  Oh, he also stated, "I should be running the newest model".

brent
Title: Re: Dunlap 208 GP separation question
Post by: Super Dave on July 01, 2003, 04:38:53 PM
This was happening in 1987 when I started racing with Dunlop K591's.  It isn't a problem.

If you want, change to Michelin's.  That's what I use.  Thank you, Tom Mason...
Title: Re: Dunlap 208 GP separation question
Post by: Dawn on July 01, 2003, 04:43:47 PM
QuoteIf you want, change to Michelin's.  That's what I use.  Thank you, Tom Mason...

Personally - if Paul's tire isn't perfect, he's not going out on it.  He runs Michelins too.

Dawn   :)
Title: Re: Dunlap 208 GP separation question
Post by: GSXR RACER MIKE on July 01, 2003, 08:46:50 PM
QuoteThis was happening in 1987 when I started racing with Dunlop K591's.  It isn't a problem.

If you want, change to Michelin's.  That's what I use.  Thank you, Tom Mason...

     Man there's a blast from the past - K591's - I had those on my '86 Ninja 900R!

     (Shameless Michelin tire sponser plug to boot - sign of a true veteran of the sport! ;) ;D LOL)
Title: Re: Dunlap 208 GP separation question
Post by: Super Dave on July 02, 2003, 05:30:37 AM
In 1987, I started racing on a GSXR750, my first bike.  When I went to my first race, I had a K391 front and a prototype K591 rear... ;D
Title: Re: Dunlap 208 GP separation question
Post by: THE_D.O.C. on July 02, 2003, 05:35:20 AM
never had an out of round or hopping tire from michelin. hell, some of them don't require weights. fantastick tires.

p.s. the fronts are amazing.
Title: Re: Dunlap 208 GP separation question
Post by: Super Dave on July 02, 2003, 06:03:38 AM
Actually, they seldom require weights.  
Title: Re: Dunlap 208 GP separation question
Post by: G 97 on July 03, 2003, 08:01:50 AM
Unfortunately it is not as simple as just switching to another brand of tire or else I would have already done so.  In any event, I need to do something.  I'm running low on wheel weights.  
Title: Re: Dunlap 208 GP separation question
Post by: Litespeed on July 03, 2003, 08:21:46 AM
I saw one that came back from a track day and the guy road on it even though you could see down through the crack to the cords.  He didn't seem to notice it while riding and said the bike didn't feel any different so I guess it is "ok".  My personal feeling is that the Dunlop dealer would be walking kinda funny with a 208GP shoved up his butt after telling me it was normal for them to do that.  Luckily for me and him I don't (never have and never will) run Dunlops on anything.
Title: Re: Dunlap 208 GP separation question
Post by: Super Dave on July 04, 2003, 12:56:50 PM
QuoteUnfortunately it is not as simple as just switching to another brand of tire or else I would have already done so.  In any event, I need to do something.  I'm running low on wheel weights.  

I understand.  The separation shouldn't be an issue.  

What's the date code on the tire?  Did you get it from Sport Tire, Jim Allen, or what?
Title: Re: Dunlap 208 GP separation question
Post by: Bernie on July 04, 2003, 08:45:48 PM
I finally got off my butt and went and looked at the rear 208 on my bike at the moment.  Badda bing.  Lovely split right accross the center.  :'(
Title: Re: Dunlap 208 GP separation question
Post by: motard11 on July 06, 2003, 08:11:58 AM
 My 208 wont ballance and is not round what should I do ?
Title: Re: Dunlap 208 GP separation question
Post by: G 97 on July 06, 2003, 09:07:26 PM
QuoteI understand.  The separation shouldn't be an issue.  

What's the date code on the tire?  Did you get it from Sport Tire, Jim Allen, or what?

Got them out East.  1701 1801.  Not fresh but both wear and traction are up to typical Dunlop standards.  Roughly 10% have done this and it is hit or miss.  I am unable to tell any difference between those that do verse those that do not.  :-/

PS The FUSA at Heartland will be interesting.  Got suspension? ;D
Title: Re: Dunlap 208 GP separation question
Post by: Super Dave on July 07, 2003, 06:38:44 PM
Kevin Elliott told me about his visit to the track...

It's a whole lot different than the last time we were there.

Thanks Ray Irwin...
Title: Re: Dunlap 208 GP separation question
Post by: G 97 on July 07, 2003, 07:16:04 PM
The good news is that Ray and Nancy are dedicated to bringing Heartland back as well as being extremely motorcycle friendly.  

The bigger cracks with the infamous sealer have been cut out and repaved.  There are still some sealer strips that are dicey as well as the white paint line that is 6-8 inches from the track edge and is slick, particularly at the apex of T-8.  Which really hampers going through T-9.  As always the drag strip sealer is ice in the morning.  Overall the track is extremely bumpy.  In fact ther is a nice little ramp at the end of pit out that when hit right can give some air.  Can't wait until repave.
Title: Re: Dunlap 208 GP separation question
Post by: motard11 on July 07, 2003, 09:11:29 PM
 Are you guys runin 208's there ;D
Title: Re: Dunlap 208 GP separation question
Post by: Super Dave on July 08, 2003, 05:43:55 AM
Bibmen tires rule...  That will be what I run.  
Title: Re: Dunlap 208 GP separation question
Post by: Tom Fredricks on July 09, 2003, 07:24:42 AM
Dave, what is a Bibmen tire?
Title: Re: Dunlap 208 GP separation question
Post by: Dawn on July 09, 2003, 07:31:48 AM
QuoteDave, what is a Bibmen tire?

Michelin's

Dawn   :)
Title: Re: Dunlap 208 GP separation question
Post by: G 97 on July 09, 2003, 12:14:25 PM
Is Bibmen related to the Stay Puff marshmallow dude?  ;D
Title: Re: Dunlap 208 GP separation question
Post by: Super Dave on July 13, 2003, 06:42:46 PM
Nah, Bib predates him quite a ways...  Bib started in 1898 in Michelin's advertising.  He usually was found smoking a cigar, with a girl on the back of his bike.  

The company motto was, I can't spell perfectly, but you'll get the idea...

"Nunk est Bibendum..."  

Translated as:  Now it is time to drink.

And the name Bib came from Bibendum...
Title: Re: Dunlap 208 GP separation question
Post by: oldguy on July 13, 2003, 07:38:50 PM
Damn, Dave, you have to be older than dirt to remember THAT! ;D