just had a new rear tire put on at the dealer and noticed today there is a crack in the tread. not very deep but about 4in long. almost like a knife slice. has anyone else ever seen this? its a stock dunlop d407

 

I have not noticed this on my tire but it could of been from a utility knife. I have seen people slash tire threads on accident like you described when they order them online and try to cut the shipping tape off of the tire.

If you are worried about it, take it back to the dealer and show them. I don't think you have anything to worry about since its only on the surface, however, you did pay for a new tire, not a new with a slash in it.

Ride safe

 

i agree... you did purchase a new tire not a slashed tire... doubt the tire would seperate,but hey ya never know.....
i have never had this an honestly dont think i could live with it..
got any pics?

 

I bought my bike used and I noticed a crack in the tread about 5in long when I got it home. I had a local indie shop look at it. They said it was ok becuase it did not extend below the tread level. Said I should keep an eye on it and if it gets bigger or starts losing air, replace it. However, if I had just bought it at the dealer like you, I'd be taking it back.

BTW, mine was the stock Dunlop as well with about 2600 miles on it. Don't know how it got the crack, previous owner said he never notice it.

 

Have it on my tire too. Guess it came from the factory that way, only noticed it a couple of months after I bought the bike. As mentioned, probably a cut with utility knife when unpacking the tires or so.

Got 5000 miles on it now and no issues with it.

 

I've seen it with car and bike tires. Probably a cut when unpacking or ran over something sharp or whatever. Who knows. I have never had a problem with my tires that had cuts on them but I would take it back just because you paid for a new tire and you should get what you paid for.