Pushing a Z6 to 14k

[Chunky]

After taking a bit of time learning how to inbed photos I'll attempt to post one of my tires as they look today. Before getting flamed I should explain that normally I would have replaced these much earlier. Textiles industries are hurting & money is tight. I'm an ultra conservative rider who has always gotten great mileage. Example: 21k out of Me880 Metzelers. New tires are planned for next weekend.

 

[ShovelStrokeEd]

Yup,

I'd say your due. From the looks of that tire, there is not another thousand in it. Wear on Z6's in particular, accelerates the further you get into the tire. Riding style and road composition can have a big effect but that one looks to have given its all.

[eakins]

since your conservative and get 21K out of 880s, i'd say put those back on. i ride hard and the 880s still work for me.

[Chunky]

since your conservative and get 21K out of 880s, i'd say put those back on. i ride hard and the 880s still work for me.

 

I wish I could put 880's on.I've been told by my dealer & a rep at Metzeler that they don't make 880s for the 2005 R1200RT. My choices are pretty much the Z6s that came with the bike or Road Pilots from Michilin.

[eakins]

since your conservative and get 21K out of 880s, i'd say put those back on. i ride hard and the 880s still work for me.

 

I wish I could put 880's on.I've been told by my dealer & a rep at Metzeler that they don't make 880s for the 2005 R1200RT. My choices are pretty much the Z6s that came with the bike or Road Pilots from Michilin.

oh, i didn't realize that the 1200rt had different size tires from the 1150rt. as metzler made the 880 available for the rear 1100rt (18" wheel) years latter after the fact the bike was old, i'm assuming they are aggressive in making the 880 available (or soon to be) for most german bikes. guess time will tell. what about the avon azaros? they have a harder rear center strip that helps promote real long life. great mileage has been reported. i've heard the z-6 have a great ride, but are widely known to wear way too fast at the end. i think for a tire design this is very unnerving as you're always wondering what if? for that reason alone i'll never use em. i don't follow the rule a german bike, must use a german tire. what ever works best, is my rule and out west that mean what ever tire last the longest. the pilot road would be my choice over the z-6.

my next set is gonna be a set of the avons and compare mileage to the 880. i roasted the 880 in 5000 miles and got 4000 out of the pilot roads. i ride fast & hard plus our roads are chewey chip'n'seal. i also mount and balance my own tires which helps out with finances.

[ShovelStrokeEd]

Your bike came with a 190-55 ZR 17 rear. They do make the 880 in a 210-50 which is going to have pretty much the same height and be just a bit wider. If you have 1/2" everywhere along the sides of your current tire you should be able to mount and run that. Think of the bling factor with that big fat meat back there.

[CopsRT]

My 2005 R1200RT came with a 180-55 ZR 17 on the rear.

[ShovelStrokeEd]

In that case, you could substitute a 170-60 with no problems. You might even like the little bit easier tip in.

[Calvin (no socks)]

I can only get 6-7000 miles on my Z6s...I think I don't ride hard, but I must be, if you get that kind of mileage...

[SteveHebert]

Bob,

 

That type of mileage is crazy! I get ab out 10K out of Z6s and am thrilled. Follow the advise here. The last 1000 or less will go extreemely fast. I had an okay looking tire turn into chord showing all the way around within 100 miles.

 

Don't leave town with that tire.

[tallman]

7,500 on my Z-6's...

some life left in tread but not worth finding out what the limit was.

I probably put on 5 sets in the mileage others may use 4 but I prefer a margin in my favor when riding on 2 wheels.

I also do a lot of 2 up riding. 'nuf said.

[Scot Earl]

Aren't there any curves in your neck of the woods?

 

Sorry - couldn't resist - I appreciate your posts.

[Gkgeiger]

I have the Metz ME880 170/60-17 on my R12Rt and love it.

[CopsRT]

What are you running on the front to go with the Metz ME880??

[Green RT]

Yup,

I'd say your due. From the looks of that tire, there is not another thousand in it. Wear on Z6's in particular, accelerates the further you get into the tire. Riding style and road composition can have a big effect but that one looks to have given its all.

 

Does the Z6 really wear more rapidly towards the end as Ed and others have suggested? Or is it just that, without any grooves in the center of the tread, you can't tell when it is close to the cord; so it appears to wear fast at the end? Inquiring minds want to know (my first set of Z6s are getting on in life).

[ShovelStrokeEd]

Will, they all wear at an increasing rate as wear progresses. The circumference of the tire decreases with wear so it has to spin faster to produce the same mph. That, in itself accelertes the wear in that the same spot on the tire covers less distance as the diameter changes so it hits the road more often at the same speed. Sounds strange, even to me, but that's how it works, I may not be explaining it all that well.

 

Back to the Z6, I think it's a little of both.

[Gkgeiger]

I'm using the Metz Me880 120/70-17 frt tire.

[Green RT]

That's an interesting point, Ed. Certainly true in principle. However, it's hard to believe that is a very significant effect. The tire is about 600 mm in diameter and changes by about 8 mm as it wears. That is a 1% change. So for concreteness, if the total life of the tire is 10,000 miles and the total wear is 4 mm (i.e. an average of 0.4 mm/1000 miles). Then, in the first 1,000 miles it would lose 0.398 mm, and in the last 1,000 miles, it would lose 4.02 mm.

[Green RT]

That should have .402 mm in the last 1000 miles.

[ShovelStrokeEd]

Will,

I'm pretty sure there is more to it than just the math. I very much doubt the rubber at 10K miles is anywhere near the same stuff that was on the tire when it was new. A combination of heat cycles and internal friction pretty much guarantees that. Some mitigation may be had from the fact that as the tire squares there is less load on the center of the tread as well but, given the tendency of those on this board to over inflate their tires, it might be more likely that the dead center of the tread will wear through to the cords first.

 

I don't know anyone who had ever done a tread depth test every thousand miles for the life of a tire. Not real sure I'd want to, either. Most of us don't start paying attention till the tire is looking pretty raggedy and then wear can seem to accelerate. I do know this. My last set of Z6's was also on my 1100S, albeit with a 170 tire on the 5.5" rim rather than the 180 it's supposed to have. That tire went off quite a bit towards the end of its life. I didn't run it down to the cords but rather hated the greasy feel of it in the rain up on the road to Red Lodge, MT. Endured, but never trusted it, down to Denver where I changed to Z4's for the next set.

[Green RT]

Ed, I agree that there is more to it than the math. Your post just prompted me to think through the decreasing radius part of the problem and that doesn't seem to be likely to be much of an effect. Rubber aging due to heat cycles and UV exposure is probably a much bigger effect. Also I wonder if there might not be some differences in the surface rubber and the deeper layers due to manufacturing processes.

[tallman]

Remember that it's not just the middle of the tire that should be considered.

When tread life is mostly gone the stress put on the sidewall when cornering is increased because the tire carcass has less integrity.

[Chunky]

It is done. Just got back from my dealer with a brand new set of Michilin Road Pilots on the RT. I had 14,350 miles on the Z6 Metzelers that came on the bike new. As I said earlier I normally wouldn't push that far but money was scarce. Paid my dealer $400 for the road pilots. Found out late yesterday I'm laid off until Dec. 01. What's a guy to do?