Thanks, Yeah, we could talk about the ultimate lap time achieved by a tire if we only were riding the track. And I have to agree pretty much completely with you on many points.
BUT in my case, this bike will seldom go to a track if ever. So the tires will wear in a very different manner. There are just times that the twisty bits of road are a long way down a freeway. And I ride my sportsbikes long distances each time I go out (just did 250 miles on the 10 Sunday). And even though I am an old guy, I am very hard on tires and brakes. That being said, I average about 1000 miles for a set of tires on a sport bike(ZX10) and 2000 on my Concours 14, I blow through a set of pads in 10k on the Concours. I thought there were no bigger pieces of junk than the Bridgestones that came on the Concours, until I tried the Pirelli Angel GTs on it. I shredded them in less than 2000 miles to where big chunks of rubber came off the tire. To verify that, it happened to two sets. The Bridgestones handling went off at about 300 miles to where you felt like you were going to not make the corner anytime you pushed a little bit. I run PR4s on it now, it squirms a bit but you know what is going on.
Having ridden for 50 years and worked in a motorcycle shop for 12 years, raced flat track and road raced (albeit many years ago) I do know when a tire goes to pot. And like the Pirellis to you, having seen so many bad things happen to a motorcycle from sliding off a road (again you see a lot working at a bike shop) and most were shod with Bridgestones, I just don't trust them.
BUT I am willing to give them a shot, I love to be surprised. But I also would like to know if the Michelins are worth a $hit.
At a track day earlier this season there were 4 accidents in the afternoon sessions and they were all on PP3. One thing I noticed is that different tires respond to different types of pavement. While I love my GPA Pros at NJMP and Summit Point, I didn't particularly like them at Mid Ohio. There are just too many factors to list and it just might be that the Bridgestones don't work well where you ride. That squirmy-ness you felt, I always feel that when I run Michelins.
As far as factors you have:
- ideal operating temp of the tire
- type of pavement
- tire carcass
- suspension setup optimal for tire brand
- weight of bike and rider on full tank/half tank/close to empty tank
- temperature of the suspension oil when the engine heats up or after a bit of compression on a spirited ride
- viscosity of the suspension oil
- How many heat cycles the tire has had
....and the list goes on.
Honestly, for street riding and mileage I'm a big fan of the Michelin Pilot Road. They corner pretty good too. Not an angular profile, it's actually more like a dunlop. And the grip is right in the middle on the spectrum. It's not great but its not exactly terrible either. I could probably run fast intermediate pace on a Michelin Pilot Road at a track day.