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Discussion Starter #1
At this point I have roughly a 1100 miles on my new Michelin 205/60R16 Primacy MXV4 non run-flat. Initially I inflated it to 33psi and ran it for about 12 miles down a dirt road with deep gravel. Almost dumped the bike in two different corners when the front end washed out at about 15 miles an hour due to gravel being so deep. In spite of that I think it is a great way to scrub in a new tire as the loose gravel is very abrasive. At least that's my theory. On the straight sections I was able to run about 40mph most of the time. After the ride on gravel I reduced the pressure to 28psi rode it at that pressure for about 350 miles of highway (which included some sweepers going over Deadman pass on I-84) and then bumped it up to 30psi for another 150 miles of two-lane through southern Oregon and northern Nevada.

At 28 and 30psi the ride is unbelievably smooth. Cornering traction was better than the either the Conti ProContact SSR or the Vanco II. In a sweeping corner near Meacham, OR I ground the side of my left boot at 70mph and never felt the tire give an bit. My experience makes me believe that both the Conti ProContact SSR and the Vanco II would have been gently drifting at that point. Truck ruts in the road had noticeably less effect on this tire than any CT I have used before.

After bumping the pressure to 34psi for the next 500 miles I can report that the ride was slightly firmer than at 28-30psi (duh) and truck ruts had slightly more effect but still much less than any rear tire I have used before, CT or MT.

Another thing I noticed is that from the time I left home until I got back my fuel mileage increased about 3 mpg and that is using GPS mileage not the bike's odometer. I will keep an eye on that as it may just be a fluke associated only with this trip, like a following wind both ways or something.


This tire provides great traction, the ride is plush, low and mid speed (up to 50mph or so) handling is also very good with easy turn-in and less tendency to stand up than the Conti run-flat or the Vanco II with its 1900 lb rated sidewalls. The fly in the ointment is that above 60 or thereabouts it wants to roll around on its sidewalls giving the bike a tendency to wallow in corners. The same effect was obvious when going in a straight line at higher speeds. In northern Nevada I had the opportunity to ride for about 5 miles at 95-100mph. At high speed with a very light grip on the handlebars it tracked basically straight but with a real sense of vagueness. Gripping the bars harder immediately induced a wallow. I think most people would not have confidence in this tire at higher speeds. I know I'm not exactly thrilled with it. To date I haven't tried it at higher pressures but my guess is that by the time I get enough pressure in the tire to stiffen its sidewalls for acceptable high speed handling I would be running on the very center of the tread. I will try it at 36psi and even 38psi and report back later but I don't think the vagueness/wallow is going to go away completely, if at all.


This tire reminds me very much of the Toyo T1R that I started with, i.e. great traction and smooth ride but poor high-speed manners. While I like the soft ride and the traction, at the inflation pressures I have used so far I cannot recommend this tire due to its high-speed instability.

MM
 

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Enjoyed the report. As you stated the tire probably needs more psi to eliminate wallow and vagueness, especially a taller sidewall 60 series.

I woulda started at 40 - 44 on any non RF. Unless you do nothing but interstate, I doubt you'll see more wear in the center even at 44 psi.

Yes, the ride won't be as plush, but it'll still be better than a cement radial with the benefits.

Did you not have some clearance issues with that monster?:shrug:
 

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Thanks for your write up! More good information! Thanks:thumbup::thumbup::thumbup:
 

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Tom.What you described is what I felt with the 205/55 Hankook ventus V4 non/RF.

It was a great tire under 80-85,Handling was great in the twistys.
But it's personality changed dramatically above 90-110 before it shook the bars so bad I gently rolled out of the throttle.

I played with psi anywhere from 34-48 and all that change at high speeds was the ride smoothness quality.The wobble was what caused me to pull it off at around 5-600 miles.

It would be a good tire for guy who don't push it,It too bad because it has a good looking tread pattern and a load rating of 1477.
But it's sidewalls certainly don't feel like it because they were very soft in the hand when I tried to flex them after I pulled the tire off my spare rim.


I like to read reports from us long timers who have tried various brands,because we know that not all BMT's are created equal,and we like to try different tires to see if we can find a better tire than the last one or an earlier tire we tried.:thumbup:


BTW:
The Conti-SSR was the worst RF I had on my bike.I could get that thing to wiggle when I gassed it in a twisty-It never lost traction.But the back of the bike could be felt when it did it.Unnerving to say the least.
 

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Since there's been so much consternation lately about different tires, I want to say that I tried the Conti RF and liked it ok. I had a Pirelli on another rim at the same time and one day I forgot what I had on the bike. I thought to myself, "dang I like this Pirelli." Come to find out, I was on the Conti at the time. Those are the only two tires I have had on and no non run flats ever.
 

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Discussion Starter #7
Trialsman,
No clearance issues at all on installation. That sort of surprised me too. I used the lay over (Lay down?) method and after about 5 secs of fighting with it I let the air out and give it a bump with my knee and it slid right in. Perhaps the easiest CT install that I have ever done. Once up and running I didn't notice any rubbing until I got it above 85 mph or so. Running at high speed in Nevada was, in part, an attempt to let the tire "rub in" and get it over with. Funny thing is when I made my next fuel stop I got down and looked at the tire to see where it had been rubbing and I couldn't really tell. I didn't give it a real close examination but there wasn't any visually obvious markings on it so I didn't worry about it anymore.
MM
 
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