Metzeler Z6 Tire Compounds

[TomR1200]

Hello,

I just switched to Metzeler Z6 Interact tires on my 2007 R12R.

Metzeler makes these tires in various compounds, and recommends different ones for different bikes (even different model BMW's). The recommended front tire for the R12R is the "standard" compound ("120/70 ZR 17 M/C (58W) TL ROADTEC Z6 INTERACT"), but the recommended rear fitment is "180/55 ZR 17 M/C (73W) TL ROADTEC Z6 INTERACT C."

The "C" on the end refers to the compound, and according to the footnotes there are about 4 available for the same tire size. Interestingly, the "C" version of the 180/55 ZR 17 tire weighs 1/2 kg more than the regular compund. Both have the same 6.5 mm tread depth.

Does anyone know if the tire compound is designated anywhere on the sidewall? Mine has no "C" anywhere that I can see. Is the "C" softer or harder than the standard compound?

Thanks, Tom

 

[marcopolo]

You sure it's the tread compound and not the tire construction? Tire companies will sometimes make tires for a specific bike to the bike manufacturer's specifications, e.g., for heavier sport-touring bikes like the RT. I think the earlier Z6 had a "C" fitment for the rear which had a stiffer sidewall. I think Michelin Pilot Road 2s also have a specific fitment (rear) for the RT and the K1300GT. When I had a "C" Z6 on my RT, it had a "C" clearly stamped on the sidewall of the tire.

 

[TomR1200]

Marcopolo,

I'm not sure. While I was waiting for the bike, I looked through a printed Metzeler 2009 tire brochure, and in the footnotes I thought it said something like "C compound". The footnotes are not available in the online fitment guide. If it were a different construction, I would also expect the tire to have a different load rating, but both are 73W.

I'd ask the dealer, but I'm still stinging from the $750 bill for two tires, mounted and balanced. (please don't ask). I'm on the road far from home, and relying on the kindness of the BMW dealer network...looks like I got the wrong rear tire on top of everything else.

Thanks for the reply. Tom

 

[roborider]

I and my buddies all ride Z6 (not interact yet, but next time) and I mount and balance the tires here in my shop. All of them have the "k" or "c" or whatever on the sidewall and the special tires cost a bit more. So if you don't see it, I'd say you didn't get it.

I'm no tire expert, but I'd say "oh well" and ride the tire to its end of life and then correct the mistake. I think this is a mistake that will bother you mentally much more than you will ever notice it in actual use on the road.

Robo

 

[TomR1200]

Robo,

Yeah, I'll do as you suggest, and it won't be an aggravation, but it's disappointing, especially since the Metzeler's are more expensive than the Contis I replaced.

Cheers, Tom

 

[roborider]

How do you like them so far, Tom?

Rob

 

[TomR1200]

Rob,

I've just put the first three hundred miles on them, all in the pouring rain. I was going very easy until I got all the mold release off, and I've just started pushing them a bit. The ride is comparable to the Contis, and I feel like they have plenty of grip in the wet. The biggest difference is the smooth, low-effort turn-in, sort of like my old R100S with skinny 1970's-tech tires.

Now for the age-old question: is the turn-in really so much better, or am I comparing them to a set of squared-off Contis with 6000 miles on them? Anyway, I'm happy enough with them. If the front doesn't cup in 3000 miles like the Continentals did, I'll be a repeat customer.

Cheers, Tom

 

[rglassma]

Robo,

Yeah, I'll do as you suggest, and it won't be an aggravation, but it's disappointing, especially since the Metzeler's are more expensive than the Contis I replaced.

Cheers, Tom

Yes, they are more expensive because the lettering says:

M I C H E L I N

You might want to try some Roadsmarts.. They seem pretty good to me and the price is better also.

 

[dorongrudo]

Z6

Used Z6 and was happy. Could not tell how worn out the tire was due to lack of center groove. Figured out that as long as the tire looks good - I am OK. Oh, I did read about those mysterious three little bumps inside the side groove. Could not find them.
Went to Canada and back (I live in Oklahoma). All was fine. I was amazed at the tire looking so good with 8000 miles on it. Once home, I took a real good look and saw fabric poking its ugly head out. I guess I am lucky to be alive. I rode fast on 105 degrees day.

Never again. My dealer only had Dunlops RoadSmart available and they are on my bike. Too early to tell but looks/feels real good

 

[TomR1200]

D,

I was scouring the sidewalls looking for my missing "C", and I found that tires now have a "TWI" molded into the sidewall where the treadwear indicator is located. Finding that first and then looking for the bumps might be the way to go.

Just to play devil's advocate, after 8000 miles on a 109 hp motorcycle, maybe one shouldn't assume the rear tire is OK?

Cheers, Tom

 

[dorongrudo]

Z6

Tom.

I did find the TWI but could not, and I did try, find the bumps.

You are right about my mistake. After 8,000 miles I should have realized that the tire is at the end of its life. As a matter of fact, I should have sought professional opinion at the 6-7,000 mile. The right thing to do was to take a detour and visit a BMW dealer on route. What I did do was ask some riders in Toronto for their opinion. The tire looked "fine" to them.

But (and there is always a "but") is that the way to ride our motorcycles? I am a firm believer in early replacement of tires. I tout it as the cheapest and best insurance a rider can get. I know that 80% of tire failers are at the last 20% of its life. What I am trying to say is that i am aware and I did ride on fabric, fast, for 800 miles on a 105 degree day.

To be fair - the Z6 held up !!!!

 

[roborider]

The z6 is not hard to read once you figure them out. Once the tread grooves that reach toward the center slick area flush out, you are done. You have maybe 500 miles left at that point before you start to see steel.

Robo

 

[TomR1200]

Update...

I called Metzeler USA in Georgia this morning, and got their customer support line. The technician was adament that substituting a standard tire when BMW and Metzler specify a special OE spec was "never, ever" acceptable. He said as a minimum it would void the tire's warranty, and that neither BMW nor Metzeler would accept any liability for failure of the standard tire.

The dealer has agreed to mount the correct tire for me tomorrow.

Cheers, Tom.

 

[roborider]

dang. Good to know!

 

[TomR1200]

Update: I went back to the dealer today, and he was unable to get a Z6 Interact 180/55 C-spec. Apparently, they are on national back-order.

He was very accomodating, and offered me a number of options. He had a set of Z6 (non-interact) tires in stock, and the rear was a C-spec, so he offered to mount the matching pair, and I took him up on it.

I got my bike, adjusted the pressures to 32/36, verified that the rear was a "C", and drove home in the rain again. I took it easy in the rain with brand new tires, but these felt like they (maybe) rode a tad harsher and (maybe) didn't have the eager, pleasing turn-in behavior of the Interacts. Who knows.

I got home and covered the bike up in a downpour, and discovered that they gave me a "K" spec FRONT tire this time. So I've gone from the "wrong" tire in back to the "wrong" tire in front now.

Just shoot me.

Cheers, Tom

 

[cjack]

I called Metzeler USA in Georgia this morning, and got their customer support line. The technician was adament that substituting a standard tire when BMW and Metzler specify a special OE spec was "never, ever" acceptable. He said as a minimum it would void the tire's warranty, and that neither BMW nor Metzeler would accept any liability for failure of the standard tire.

The dealer has agreed to mount the correct tire for me tomorrow.

Cheers, Tom.

What else could he say?
Once when someone I know called, they told him that the tires are spec'ed at max speed stability according to the different characteristics of the "C" or "K" etc.

 

[TomR1200]

Wrapup: The dealer cannot locate the correct front tire before I need to depart for home. Too bad, so sad.

Conclusion: I went into Frank's BMW in Essex Junction, VT for a tire change and walked out $750 lighter, with one tire that the Metzeler rep says will carry no warranty when installed on my bike.

It's crap like this that drives people back to Hondas.

Cheers, Tom

 

[bernieecht]

I do not see a problem here. Metzler's German website says that you can use either the regular Z-6 or Interact Z-6 on the front with either the regular Z-6 Code "C" or the Interact Z-6 Code "C".
I do not see how BMW or Metzler can void there warranty. Do not worry.
After all BMW and Metzler have approved the use of either one or combination of it.
Keep them aired up and enjoy your new tires.

Quote from http://www.metzelermoto.de/web/fitm...ehicle=114142&versionVehicle=222144&consent=Y

ROADTEC Z6 INTERACT ROADTEC Z6 INTERACT
Front Rear
120/70 ZR 17 M/C (58W) TL ROADTEC Z6 INTERACT Front - 2.5 BAR 180/55 ZR 17 M/C (73W) TL ROADTEC Z6 INTERACT C - 2.9 BAR
Note: Freigabe liegt vor. Eintrag nicht notwendig. Zertifikat muss mitgef??hrt werden..
PDF downloaden

ROADTEC Z6 INTERACT ROADTEC Z6
Front Rear
120/70 ZR 17 M/C (58W) TL ROADTEC Z6 INTERACT Front - 2.5 BAR 180/55 ZR 17 M/C (73W) TL ROADTEC Z6 C - 2.9 BAR
Note: Freigabe liegt vor. Eintrag nicht notwendig. Zertifikat muss mitgef??hrt werden..
PDF downloaden

ROADTEC Z6 ROADTEC Z6 INTERACT
Front Rear
120/70 ZR 17 M/C (58W) TL ROADTEC Z6 Front - 2.5 BAR 180/55 ZR 17 M/C (73W) TL ROADTEC Z6 INTERACT C - 2.9 BAR
Note: Freigabe liegt vor. Eintrag nicht notwendig. Zertifikat muss mitgef??hrt werden..
PDF downloaden

ROADTEC Z6 ROADTEC Z6
Front Rear
120/70 ZR 17 M/C (58W) TL ROADTEC Z6 Front - 2.5 BAR 180/55 ZR 17 M/C (73W) TL ROADTEC Z6 C - 2.9 BAR
Note: Bereits in den Fahrzeugpapieren eingetragen.

 

[TomR1200]

Bernie,

Thanks for the translation! Actually, the rear is now OK, but I'm heading home with a "K" code FRONT tire, which doesn't seem to be right for my bike, in any language.

Cheers, Tom

 

[bernieecht]

Yes, you a right. That is the tire for a R1200RT. But I do not think it will cause you any problems.
My RT came with Z-6 tires from the factory, but with no codes. They did not last as long as the owns with a code. But Metzler said there is no difference.
The funny thing is that if you search the US site, they do not list any tires for a R1200R, but on the German site there are several choices and combos, as you saw.