As a result of some requests for further detail about the Michelin versus Dunlop article in the December 1997 issue of Wing World, I'd like to expand on some of the facts behind the article.
As was stated in the story, I normally get anywhere from 16,000 to 20,000 miles out of a rear Dunlop Elite II tire (I got only 13,000 on the OEM K177s). I ride year round in all sorts of conditions, on all sorts of roads, with all sorts of loads. I would consider myself a fairly aggressive rider. In fact, after one trip to Deals Gap, an experienced Honda technician asked if I had been "racing" my Wing because he found scrapes on the heads of the lower cowling screws he had never seen on anyone's bike before.
So, why did I get only 9,500 miles out of my rear Michelin radial, and other '`aggressive" riders get 13-14,000? The answer is "I don't know." There are so many variables on tires you can't put your finger on just one. Here are the ones I know can affect wear — I'm sure there are more:
The general answer is that the rear will almost always wear out quicker because that is where the bike's motive force is transmitted to the road surface. Every time you hit a highway expansion joint, the bump, no matter how slight, will lessen the load on the rear tire causing it to lose traction briefly. Every time you start up from a stop, additional slippage occurs at the rear tire. Multiply this times the thousands (millions) of surface irregularities we hit, and the times we take off, and you can see where this is true.
Now, if your road surfaces tend to be less rough than mine, my tire will probably wear out quicker than yours. Perhaps if I ride in a colder climate, my tire will operate at a cooler temperature making it harder than yours, therefore not wearing as quickly. Maybe my rear axle is fractionally more out of line than yours, therefore the tire will scuff infinitesimally. (Did I use that word?) These variables can add up, thus everyone's conditions are a little different. I know Michelin is working on its tread compounds to see if they can "get it right" so maybe some people have a harder compound than others.
They also may be experimenting with tread depth. (I believe tread depth is where their biggest problem is.) My new Michelin only had 7.5/32nds versus a new Dunlop with 11/32nds. That's 32% less tread depth to start with.
My overall tread wear average was 1500 miles per 32nd. That's 5250 miles "difference" the way I calculate it, just from tread depth. But Michelin can't just put additional tread on the tire. There are so many other variables involved. If the tread is soft, therefore giving us the cornering and grip that we identified, making it deeper with the same consistency might cause the tread to roll or squirm which would make it wear even quicker. If they make the tread harder to accommodate the deeper cross section, they risk changing the handling characteristics.
I'm no tire engineer, but I do know Michelin is dedicated and concerned about making a good tire that meets our needs (good service life and excellent handling). I think part of their problem is tires are engineered and manufactured in Europe where they have a totally different mind set about riding than we do. I sincerely hope they can get a consistent product that will not change the way the current tire handles. Other than the wear factor, it is one heck of a tire.
I hope this long dissertation sheds some light on why there is so much variability in tires. Kathy's and my evaluation tried to minimize these variables so we could cut through some of the haze. Unfortunately there are no clear cut answers. Michelin does need to do some more work on their tires. Dunlop needs to do some work on theirs, too. They shouldn't sit still. Collectively, we pay millions of dollars a year for tires and we deserve the best. l would gladly pay a little more for a tire with superior handling (in fact, I did). If they would get even 75% of the life of the Dunlop Elite IIs, I would be ecstatic. For me, they get enough mileage to make it a very difficult call. Other people have gotten only 78,000 miles from the 79X, still others have gotten 13- 14,000 miles. When Michelin gets it to where I can get 13-15,000 miles and have the same handling that they have now, their will be no question which tire I will go with.
As with everything else in life, the decision is yours and yours alone. Every tire model is different. You cannot generalize. The OEM Dunlop K177s are different from the Elite IIs which are different from the Michelins which are different from the Continentals. They are all made differently with different compounds for different bikes. (I have a friend who gets only 5,0006,000 miles out of his Dunlops on his BMW; he would love to get the 9,500 I got on the Michelins). So, the choice is yours.
Finally, Jim Waymire, GWRRA #117419, of Simi Valley, California, noted my account of an instance of terrible handling with the Michelins on a certain road condition (construction area), and asked for a bit of elaboration.
It was in New York State, and crews were repaving a two lane road section, and had removed the asphalt down to the gravel bed. The surface was washboard with shallow grooves (one inch or so deep) running across the surface about every six inches. The looseness of the gravel combined with the groove spacing made for basically no directional stability in the front end at all. It really was disconcerting. I had to slow down to about 5-10 mph, while Kathy on the Dunlops went off and left me at 20-30 mph. It only lasted a couple of miles or so, but I was really sweating it during that time.
That was the only place the Michelins' handling was ever compromised. Unless I lived in an area where this type of road surface is common, that certainly wouldn't be a factor in my buying decision.
Incidentally, Dunlop has responded to our tire evaluation article in the December issue of Wing World. (See "P.O. Box" this issue.)
Dunlop's national sales manager says the Buffalo, New York, corporation did not realize many of us really care about the way that our Wings handle and perform versus how many miles we can get out of the tires. Buckley invites us to tell Dunlop about the way we Gold Wing riders use our bikes, so here is your chance. Send your comments about the kind of performance you'd like from a set of Gold Wing tires to Mike Manning, Product Manager, Dunlop Tire Corporation, PO. Box 1109, Buffalo, New York 14240-1109, or via e-mail to mmanning@dunloptire.com.
If we do this logically and rationally, maybe something can come from all of this, and we can get some tires that will do what we want them to. Please give them straightforward information, not emotional tirades.
Reproduced here with permission of Nick Hoppner, Editor - Wing World Magazine. This article originally appeared on page 37 of the February 1998 issue.