This is the factory Dunlop on the rear my 2019 SGS with just over 14k miles. Went for a nice long ride today, and discovered these slits on the edges when I got home. Bike felt a little squirrelly on grooved concrete. School me - what's going on here?

 

Have never seen that on any of my bikes. I’m usually a lot thinner on tread at 14k with a Dunlop as well.

Do you do most of your riding in a straight line? Not sure if it’s the picture angle but the tire seems to flat down the middle.

If it doesn’t feel stable change it, 14k isn’t too bad.

 

Dual compound tire, edge of the compound?

 

[img]blob:https://www.hdforums.com/248e8613-9e8c-43d6-b239-e1c673ada227[/img]
This one is more worn out but looks more rounded.

 

Yes, most of our riding in the southern Nevada desert is on a highway or interstates, not a lot of twisties here, but I do rip into turns given the chance. I've never seen this before either, but compound separation seems logical, and was my first thought. I've always maintained the tire pressure, and ride solo 100% of the time, so it's not overloaded or operator error.

 

I have seen that a few times with dunlop. Im guessing the tires are cupped by that mileage and need replacement anyway.

 

Just a couple of observations. Carefully maintaining a tire pressure that is too low still results in a tire that is under inflated and and leads to the problems caused by under inflation, so what pressure have you been carefully maintaining? Reaction to grooved road surface increases with wear, regardless of whether there are other problems with the tire. That is why new tires always seem so great. Some tires react more than others at the same wear level, that is part of what makes other than the factory tires so popular. From the depictions I have seen, the strip of harder rubber in the center for improved mileage wear is considerably more narrow than where the slits are on your tire. I have NO IDEA what the cause might be, but I don't believe that is where the compound changes. Dunlop has had several problems since the new frames were introduced, including sidewall checking and small chunks coming out of the tread near the center of the tread area. What you have may be a new problem and it wouldn't hurt to send the pics to Dunlop. They may say that 14,000+ miles is about all you should expect (no warrantee help toward new tires) but they may be interested in the slits about the same distance off center on both sides and may even be able to tell what has happened.

 

40 rear, 36 front pursuant to the owners manual. I did send them an email out of curiosity, if they reply I'll share what the had to say about it.

 

their warrantee is not mileage based, it is time and tread wear based.

dunlops warrantee: https://www.dunlopmotorcycletires.co...warranty-info/

AFTER 50% TREAD WEAR

If, after the first fifty percent (50%) of tread wear, the tire becomes unserviceable for a condition covered by this warranty, your Dunlop motorcycle tire retailer will replace it with a comparable new Dunlop tire at a cost calculated in the following manner:

1. Either your original buying price substantiated by invoice, or the retailer’s current selling price, times (x)
2. Fifty percent (50%)
3. Plus (+) all applicable federal excise taxes, and local taxes and all charges for retailer services such as mounting and balancing.

WHAT IS NOT COVERED

• Tires worn beyond the last one thirty-second of an inch (1/32”) of original tread depth. Beyond this point, the tire has delivered its original tread life and there is no warranty regardless of its age or mileage.
• Tires submitted for unserviceability before wear-out (1/32” tread depth remaining), but more than 72 months after the week of manufacture as determined by the US Department of Transportation serial identification number.

 

Also looks like 2 X 4 to me.

No tire will corner well when squared like that one looks.