I was thinking of going to a 180 rear tire because it would turn faster. Pirelli Angel GT makes an A spec which is a heavy carcass and would most likely hold up pretty well under the circumstance. It may wear a little more than the 190 but will definitely be sportier.

Has anyone ever ridden a 14 with the 180 rear or is this taboo?

I wouldn't go smaller with the OEM wheel. If anything, try a 190/55 or lower the front end slightly.

I've tried about 6 or 7 190/55s. I guess they are made for a 190 rim but they are narrower at the center and that is where it counts for cornering stability.

The more closely the center of the bike is aligned with the center of the tire, the more stable and predictable the steering is. Straight up and down = totally stable and the bike steers itself. Lean the bike, you no longer are riding the center of the tire, the center of the tire is no longer in line with the center of the bike. There is no way to escape that, you give up stability and predictability in steering for leaning a bike. The old school answer was to use a narrower tire. If the tire is narrow, it steers quicker because the radius is of course smaller. The center of the bike also shifts less from the center of the tire when in a lean on a narrower tire. One reason 600s steer more easily than a larger bike.

1990, all sportbike tires were approximately circular in profile.

SO why did they put big honkin 200/60 rear tires on a 1000 since the 1990s then?.....looks cooler but would steer better with a narrow tire like a 600 cc bike has. The taller tire lifts the rear and steepens rake of the forks which improves steering quickness so it was not all downhill with the taller rear tire. Still, not an even trade to steepen the rake in exchange for increasing the discrepancy in alignment of the center of the tire with the center of the bike while in a lean. Solution: quit making 190 and 200/55s and 60s circular. Make the profile elliptical. Now you have a tall tire to steepen the rake and it also has a narrow center. Optimizes the alignment between the center of the bike and the center of the tire as much as possible and also steepens the rake. Not only that, you have a larger contact patch while in a deep lean. This would all be very clear if I could show you illustrations of how the old circular profile tires compare to the newer elliptical profile tires.

If you use a 180, I think you are going in the wrong direction. The rim is 190 wide. Put a 180 on there and now the tire has to deform to make up the missing 10 milimeters of width. The tire will become less elliptical. It will behave more like a tire that has the center tread worn with no side wear. Also seems more likely the bead could break accidentally using a narrower tire than what the rim was designed for.

ALL 190/55s I have used are visibly more elliptical in profile compared to the three stock 190/50s Ive had on my bikes. The only 190/55 I have used that was circular in profile was the Bridgestone RS10. A lot of people love RS10s but it doesn't handle as well as any of the other 190/55s I've used and I'm sure that is because of the circular profile which is wide compared to the elliptical profile which is narrow. My chicken strips are bigger on the RS10.

Try a 190/55 and see how it handles. If you like it, note how close it comes to inside front of the swigarm. If you have enough space, try a 190/60 when you wear out the 190/55. You might even try a 200/55 or 200/60 which will squeeze down and probably make the tire deform a few milimeters taller.

* Last updated by: Rook on 10/19/2020 @ 3:55 PM *

Lesson learned...it's not just 170, 180, 190 but circular vs elliptical profile, etc.... I'll stick with OEM and call it a day. I do like the 180 on my Ducati though....but it is also OEM on that bike.

Are you doing track days? If not you never see the benefit of a 200/55 SuperaCorsa type tire. On the street you would notice a smaller tall tire handling mobetta than a big tall SuperaCorsa but I think its just more flickable.

Rook said this much more elegantly and technically than I did. I took off the SuperaCorsa and put on an P Angel 200/55 something or other, love the tire stability and handling.

.it's not just 170, 180, 190 but circular vs elliptical profile, etc.... I'll stick with OEM and call it a day.

I noticed the 190/55s I have used tend to be more elliptical than 190/50s I had on my ZX-14 and my busa. I'd try a 190/55 but stay away from the Bridgestone RS10 if you want elliptical. A 190/55 will raise the tail about 4 or 5 millimeters which makes a noticeable difference in turn in quickness. If you have some chain stretch, you might fit a 200/55. I've never tried one because I don't know if it would fit with my +3 T rear sprocket. The Gen2 swingarm is not the same as the Gen1. I'm pretty sure someone on here verified a 190/55 would fit a Gen2 though.

* Last updated by: Rook on 10/20/2020 @ 4:58 PM *