The first feature is the dual compound tread front and back. A harder material in the center of the tire provides long life for driving for an extended time on the freeway, and a softer material on the sides allows for better grip in the corners.
Perhaps the most significant feature of the PR3 is the molded siping front and rear. This makes them arguably better than any other tire for wet conditions. The siping breaks the film of water on the road and helps channel water away to increase traction. Additionally, they should heat up quicker, and remain cooler than other tires, providing optimal traction in all weather.
To learn more about the physical advantages of the new tires, I spoke with a very helpful gentleman named Bill at Michelin Customer Support. He was able to tell me the weight of my new tires, but was unable to find information on the weight of the older Pilot Roads, or the moment of inertia for either. He is going to send me any information he can find once he talks to an engineer. I will post an update once I learn more about this. Aside from stopping distance, weight and inertia are two of the most significant performance aspects of a tire.
At the local shops, the PR3 was one of the less expensive tires they were offering, though availability was questionable at best. I found an online bike store that had them in stock, and with shipping included they were a really good deal. Once the tires arrived, finding a shop that would do it without severely punishing me for buying on line was a trick (more on that at a later date). Thankfully, my favorite shop had the best pricing, and was able to get it done right away.
On the day after they were installed, we woke up to a heavy frost, the first of the season. The roads were dry but the air sharp; biting though my scarf and winter gloves on the freeway. One nice thing about an un-fared, air-cooled machine is the ability to warm up by hugging the engine at stoplights. Upon arriving at work, I checked the tires before going in. Less than 50 miles into the new tires, they were already showing a rough sheen on the tread surface, indicating that they were well on their way to being broken in. Also of note was that the contact surface of the tire was warm to the touch, even in the freezing air. The old tires never warmed up like that…
Heading home that evening, a storm-front passed though, scattering autumn leaves and an abundance of rain all over the roads. Traction was superb however; once I was out of traffic, panic braking tests indicate that the new tires may work better on debris-strewn wet surfaces as the old ones did on clean dry pavement.
I have ridden on these for about a week now, and at 130 miles they should be fully broken in. First impressions are good. Riding on rounded tires, rather than the, edgy, worn, old ones, are a nice change: the bike holds a solid, smooth line through corners at any speed. Before, the squared-off tire shape and odd geometry (from wear and mismatched tires) tried to push the bike upright and turn the handlebars. My commute is a mix of surface streets and freeway, new pavement and old, and so far, the responsiveness and feedback seems far improved. I am no longer as afraid of breaking loose without warning. Because the PR3s grip so much better than the old tires, bad surfaces such as paint and tar-snakes are more noticeable though: I am more likely to hit them while on the throttle or in a tighter lean. Time will tell if they hold up well long-term, but for now, I am excited to ride these through the winter!
The technical breakdown
Bike: 2002 Suzuki GSF1200S
Rear tire: 180/55ZR17
Front tire: 120/70ZR17