Sumitomo Htrziii Directional?

[beviking]

Got the wheel/tire package from AM with the above named tires. Only indicator on the tires is "outside" and no directional arrow or anything. My neighbor insists they are directional/unidirectional because of the tread pattern. If you look at the center of the tread, that "swoosh" line seems to have to roll forward, otherwise it would be channeling water towards the center of the tire as would the angled channels on the next rib out?

Sumitomo High Performance HTR Z III Tire (245/45-19) 5517923 - Free Shipping!

Checked all over the web, no reference to them being directional. Just another crazy neighbor?

 

[Ronin38]

They are Asymmetrical, but not directional. The inner and outer shoulder design is different, and much more important that the tread pattern. I used these for my "track tires" on my last car and liked them very much! I did a track day at NJMP on Thunderbolt in the rain, and they worked beautifully, but that was on an AWD car, too.

 

[beviking]

That makes me feel better Ronin38, thanks. Just got a reply from AM..

"The tread is directional. I hope this helps.
If you have any other questions, please feel free to contact us.
Thanks and have a great day!

**** *.
Customer Support
AmericanMuscle.com
866-727-1266
Fax: 610-251-0263"

...I asterixed the name in case that person is human and just didn't put the "not" between "is" and "directional". If it isn't a typ-o, that doesn't make me feel better

 

[Ronin38]

The markings on the tire are there for a reason.

For example, the Dunlop Star Spec's are Directional, and have an arrow pointing in the proper direction of rotation on the sidewalls. From TR's website: "The Direzza Sport Z1 Star Spec tread compound is molded into a directional design featuring notched, continuous shoulder ribs, large intermediate shoulder blocks and a wide center rib to deliver consistent contact with the road and enhance grip during cornering." So long as the rotation is in the direction of the arrows, you can mount the tire on either side of the car, but it still rolls the same direction.

The Sumi's just say "Outside, with no arrow."
"The Sumitomo HTR Z III features a silica-enhanced tread compound molded into a sophisticated, 5-rib, asymmetric tread design." You can mount these on either side of the car, but with the "outside"-out, the tire would be rolling in either direction.

If your neighbor likes tread patterns, tell him to look at the stock P-Zero Nero All-Season tires. The tread pattern goes "both" ways! It's also Asymmetrical (and says "Outer" on the outside), but not Directional.

 

[Merc63]

As was said, they are asymmetrical, but not directional, and work just fine so long as the outside is out. I use them on my daily driver BMW and they work in everything but snow (of course).

 

[beviking]

Sweet! Thanks guys! I googled asymmetrical tires and found this on tirerack...

'One of the most frequently asked questions is "I mounted my asymmetric tread car tires purchased online and it looks like two of the tires are running backwards. Did I get two of the wrong tires?"

The answer is "no," you did not get the wrong tires! The critical part of the tires in question is the outboard side being mounted out. Typically the outboard is going to have bigger tread blocks to stand up to the stresses of cornering better than the smaller tread blocks on the inside of the tread. Between the shoulder tread blocks some tread patterns seem to be running backwards, the significance of this appearance is overshadowed by the necessity to mount the outboard shoulder on the outside of the wheel.

So if you have the appearance of two of the tires running backward when looking at the tread but have the outside sidewall mounted out the tire is mounted correctly.'

Sometimes I wonder how I made it this far

 

[beviking]

Got an email from AM customer support and the above email about them being directional was a mistake. Glad I don't have to deal with switching the tires!
Hope there's no hard feelings from AM for questioning their work
As for the neighbor