Author Topic: Dunlop Tire Cracks, Should I Be Worried Yet? (pics)  (Read 2192 times)

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Offline jeffcampagna

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Dunlop Tire Cracks, Should I Be Worried Yet? (pics)
« on: July 24, 2016, 12:33:47 PM »
Hey folks,

Just noticed these cracks on  my 1977 CB550's front Dunlop Qualifier. Looking for some guidance from all you more experience riders out there. Are these cracks worth putting off riding until I get a new front? Or should they be fine for a few more weeks?

Thoughts?

Offline ekpent

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Re: Dunlop Tire Cracks, Should I Be Worried Yet? (pics)
« Reply #1 on: July 24, 2016, 12:48:40 PM »
  I've rode worse on some new project bikes but don't tell anybody please  ;)   Time for some new rubber though in the near future. Any idea how old those are, may be a date code on the sidewall.
   Your the one though that needs to make the decision to take the risk or not and what value to place on your well being.
« Last Edit: July 24, 2016, 12:59:24 PM by ekpent »

Offline calj737

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Re: Dunlop Tire Cracks, Should I Be Worried Yet? (pics)
« Reply #2 on: July 24, 2016, 01:28:58 PM »
I wouldn't push my bike with tires on it like those, let alone ride it. Your neck, you decide if the only piece of safety gear on your entire bike in touch with the road looks like that.
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Offline jeffcampagna

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Re: Dunlop Tire Cracks, Should I Be Worried Yet? (pics)
« Reply #3 on: July 24, 2016, 05:54:28 PM »
Thanks for the advice guys! Was looking at new rubber anyway. Just means I'll have to go about it sooner. Wife won't be pleased.... ;)

Offline jonda500

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Re: Dunlop Tire Cracks, Should I Be Worried Yet? (pics)
« Reply #4 on: July 24, 2016, 06:09:25 PM »
No-one will recommend riding on that tyre! I think everyone loves having nice new safe tyres!
My second 500 had old cracked Dunlop Qualifiers on it when I got it (they sure looked kool!)- I took it up to 80mph on those, but only on test rides - I was far too too excited to wait. But then I do have more of a death wish than most, so please avoid riding it till you replace that tyre or at least don't push hard it around corners!
John
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A starter clutch thread:
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Offline scottly

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Re: Dunlop Tire Cracks, Should I Be Worried Yet? (pics)
« Reply #5 on: July 24, 2016, 09:40:52 PM »
  I've rode worse on some new project bikes but don't tell anybody please  ;)   
I have, too... ::)
Jeff, explain to your wife that the tire is unsafe; if she loves you, she will encourage you to purchase a new, safe tire. If she refuses, get a new wife, since she obviously doesn't love you and has no concern for your safety. ;D   
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Offline dhall57

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Re: Dunlop Tire Cracks, Should I Be Worried Yet? (pics)
« Reply #6 on: July 24, 2016, 11:56:42 PM »
I wouldn't push my bike with tires on it like those, let alone ride it.
I agree cal. That's pretty bad. I just replaced tires on my project K4 with Continental's. The 40 year old tires that came on the bike looked in better shape than what is on yours Jeff. But wasn't going to ride around of 40 year old tires though. I value my life to much ;)
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Re: Dunlop Tire Cracks, Should I Be Worried Yet? (pics)
« Reply #7 on: July 25, 2016, 03:21:01 AM »
The users guide to my car recommend replacement of tires before 6 years old when reduced speed should be used...
CB750 K6-76  970cc (Earlier 1005cc JMR Billet block on the shelf waiting for a comeback)
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K2 engine build thread. For a complete CB750 -75
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Offline strynboen

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Re: Dunlop Tire Cracks, Should I Be Worried Yet? (pics)
« Reply #8 on: July 25, 2016, 03:21:17 AM »
its not only the cracks...the rubber is( stone? stoned.) mean ).hard..and give a bumby ride..specily on the road lines(stripes)..you vill hang ,on them..like the bike dont vant to go over ,,and steer you aut in the dirt.(.a soft new tire..vill steer like you demand)..and wobbel can be direkt konsekvens of old hard tires vho not follovs the road konture..and ..yes they can explode too......
i kan not speak english/but trying!!
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Offline jeffcampagna

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Re: Dunlop Tire Cracks, Should I Be Worried Yet? (pics)
« Reply #9 on: July 25, 2016, 04:10:23 AM »
Interesting Strynboen. I have noticed this bike has a serious wobble at times and yeah, when I get caught in one of those black tar lines in the asphalt, it feels like I'm going to eat #$%*. Didn't know it was caused by hard tires. Thanks for the input.

Offline ekpent

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Re: Dunlop Tire Cracks, Should I Be Worried Yet? (pics)
« Reply #10 on: July 25, 2016, 04:50:21 AM »
  While you have the front tire off and the bike on its center stand or other means check your steering bearings for notchiness and smoothness. Most old Honda's benefit from the more modern tapered bearings. Might make a good weekend or winter project if you feel something abnormal and help the handling.

Offline jeffcampagna

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Re: Dunlop Tire Cracks, Should I Be Worried Yet? (pics)
« Reply #11 on: July 25, 2016, 07:25:58 PM »
Well, just pulled the trigger on a set of Dunlop k70s. Can't get em in Canada so had to get em off ebay and ship them up. Shipping was almost as much as the rubber. But there's only one place in Canada that sells k70s online and they're out of stock apparently.

I know the k70s have their critics but from what I read, they're a great combination of performance and vintage tread pattern. The k81s just don't do it for me.

Thanks for the advice guys.

Offline Gene

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Re: Dunlop Tire Cracks, Should I Be Worried Yet? (pics)
« Reply #12 on: July 25, 2016, 08:07:01 PM »
If you have to go with Dunlops (I don't know why, to be honest, but I hate 'em) the k70's are the ones to go with.

Actually, I do know why . . . Dunlops tend to be on the soft side, they're racing tires, or at least were forever, so they're meant to grab-n-go.  They wear out faster.  That's been my experience on cars anyway, not bikes, got such a bad taste I swore I'd never use them.

Anyway - good for you, new tires are always a blessing.
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Offline Stev-o

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Re: Dunlop Tire Cracks, Should I Be Worried Yet? (pics)
« Reply #13 on: July 25, 2016, 08:29:38 PM »
  I've rode worse on some new project bikes but don't tell anybody please  ;)   
I have, too... ::)


+1.  Guess thats why the wifey upped my life insurance policy last year!
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Offline cb650

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Re: Dunlop Tire Cracks, Should I Be Worried Yet? (pics)
« Reply #14 on: July 26, 2016, 02:50:58 AM »
They havent even been made in 15 or so years.    Being on the front   Has to go.
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Offline brewsky

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Re: Dunlop Tire Cracks, Should I Be Worried Yet? (pics)
« Reply #15 on: July 26, 2016, 03:19:13 AM »
  I've rode worse on some new project bikes but don't tell anybody please  ;)   

I picked up a fresh barn find F650 BMW with tires that looked exactly like that. After getting it running, I was too eager (stupid) to wait for the new tires to arrive to see if it would do the advertised 100 mph top speed. (it did)

Slowing down, I heard and felt a "thump, thump, thump", and discovered the tube was coming thru one of the cracks in the tread.
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Offline 70CB750

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Re: Dunlop Tire Cracks, Should I Be Worried Yet? (pics)
« Reply #16 on: July 26, 2016, 03:41:08 AM »
Wheels for Red came with 404 Dunlops, by the stamp the tires are 2004.  I put 3000 miles on them and I am about to replace them now.  ;D
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