What's Wrong with this Tire??

[twilmotte]

I noticed both of my Michelin Pilot Roads (with 6000 miles on them) have this "groove" that runs around the entire circumference of the tires. I've attached a photo of my rear tire. My riding buddy also has a similar groove around the entire circumference of his front Pilot Road (with 3000 mileage). I ride an R1150RT; he's on a K1200RS. Has anyone seen this "grooving" before on Michelins? I'm wondering if it's a defect in the tire molding process. Even though the groove doesn't appear to extend into the tire cords, I'm also wondering if it's a safety hazard. Do you think it would do any good to contact Michelin customer service?

[3rdbike]

Appears to be from the mold??? Have you gone back to the dealer you've purchased the tires from, and asked them to inquire about it with their distributor? Has anyone else had the same problem, etc.? Or, as you're thinking, contacting Michelin customer service.

[fatbob]

Tom:

I've never seen that before, and on your buddy's bike too?! Wierd. I'd go get some Metzellers real fast, ME880's. Michelin should be able to explain it, or replace the tires.

 

Bob

[ShovelStrokeEd]

The one on the back of my S had a similar thing going for awhile. It wore away eventually. 12K miles and nary a problem. I wouldn't worry about it.

 

Note also that its depth does not extend into the tread grooves.

[russell_bynum]

I just took a Pilot Road off my RT that looked like that. Not sure what caused it. I ran the hell out of that tire and didn't have any grip or handling issues.

[jacko]

yeah I have had 2 sets of Pilot Roads they did that also

dont worry about it,

regards Jacko

[scottfarm2]

That's the early warning failure groove. Just kidding. My roads did the same thing. I have gone to metzler roadtec 6's --no whining tires and better milage and just as sticky if not more.

[Mike O]

I just took a Pilot Road off my RT that looked like that. Not sure what caused it. I ran the hell out of that tire and didn't have any grip or handling issues.

 

Ditto...have had 2 sets; both did the same thing.

 

Regards,

 

Mike O

[No_Twilight]

Don't know about the groove but why is it so shiney?

[twilmotte]

Thanks for your inputs. Nice to know other riders have seen the same thing and haven't had any problems as a result. BTW, the tire looks shiney 'cause I just put a nice coat of Armor All on it. Just kidding! (I wet them with water to make the groove show up better in the photo.) I am going to contact Michelin to see what they say and I'll report back to the forum.

[steve.foote]

BTW, the tire looks shiney 'cause I just put a nice coat of Armor All on it. Just kidding!

 

Nice! I was jumping for the keyboard when I first started reading that.

[Airtire]

Something I know for a change....

 

The groove in center is where the two halves of the mold meet. This is what we call flashing. It is perfectly normal and should wear off over time. This tire was produced in a two piece, full circle mold. You may notice that some tires have this line, wheras others are made in a segmented mold which is 5-7 separate segments and leave lines across the tread versus around it. It is a normal condition, just like the little "tits" (sorry Wurty) that are on a new tire.

[Stan Walker]

The groove in center is where the two halves of the mold meet.

 

I've got about 11,000 miles on a pair of pilot roads on my R1150RT. I have one such line in each tire, about 3/4" right of center. This is in a moderately worn area of the tires. These lines don't go into the tire like a cut or a defect would.

 

I think it is a place where two serparate pieces of rubber were joined but they have different compositions and different wear patterns. After awhile it leaves a small difference in height, like a curb, because the softer rubber wears away faster than the harder rubber right next to it.

 

Stan

[Airtire]

Here are some pictures to show what I mean. Excluding the new dual compound Michelin racing tires (Hard center, soft sides), the tires are not built on two sides. Once they are put in the mold, the rubber starts to flow and fill the cavity. It would be impossible to contain two compounds if they were exactly in the center unless there was a tread groove in the exact center.

 

Note the line in the middle using full circle mold

Note the line going across, not down the center using segmented mold

Picture of one of our segmented motorcycle molds

Picture of one of our full circle aircraft molds

[Stan Walker]

Excluding the new dual compound Michelin racing tires (Hard center, soft sides), the tires are not built on two sides. Once they are put in the mold, the rubber starts to flow and fill the cavity. It would be impossible to contain two compounds if they were exactly in the center unless there was a tread groove in the exact center

 

So you are saying what we have isn't possible. OK. I'll blame it on the drink I had the other night.

 

Stan

[twilmotte]

A few weeks ago I posted a photo of my Michelin Pilot Road rear tire, showing a wierd looking groove around the entire circumference of the tire. (See original post.) Several members said they have seen the same groove on their Pilot Roads and that the groove caused them no problems. I mentioned I would send a copy of the photo to Michelin, expressing my concerns and get back to this forum with the Michelin reply. This is verbatim the email Michelin sent to me:

 

"Dear Mr. Wilmotte,

 

The center strip seen in your tire is special material engineered

to disperse static electricity from within the tire. This strip can

cause some appearance modification after some wear. This

modification has no effect on the performance of the tire making

this condition cosmetic.

 

If you have additional questions, please respond to this email

or you may call us at 1-800-847-3435 (toll-free) between

8:30AM and 6:00PM Eastern Time Monday through Friday to allow

one of our Consumer Relations Representatives to assist you.

 

<issue.Brand.description3 is NULL>

Consumer Relations Department

 

(Please Do Not Delete the line below.)

Email ID: 1483625"

 

After reading the Michelin response, I'd still rather not have any groove in my tires (groove in front tire, too). I'm continuing to ride on the tires (7,500 miles to date) because of the testimony of several forum members who've experienced the same groove in their Michelins. However, I'm only about 1500 more miles away from my next set of tires -- Metzeler 880s.