Motorcycle tires will scallop no matter what tire pressure is used. They have to scallop because the tire profile is rounded. The distance from the outer edges of the contact patch is closer to the axle than the tread at the center of the contact patch. Yeah, when the tire is deformed carrying mass on the contact patch the distance to the axle is the same but the circumference of the tire at those points is not. Therefore for the distance the motorcycle travels parts of the tread go farther, parts go shorter. The contact patch must scrub for the wheel to roll.Spininprop wrote: ↑Sun Oct 02, 2022 1:27 pm Yep, Road 5 are great, but totally agree about scallop and I have used increments from 38 to 42 front psi but could not find a pressure that they will not cup, scallop, or otherwise deform. But they are great in the dry or wet. So much so, ill go with them or road 6 when i need to replace the OEM junk. What I did find out was a trip to a few hours of warm twisty running would reshape them to the point they would not vibrate under braking.
When the contact patch scrubs tread blocks stretch and compresses. This is what causes the scalloping/feathering wear which repeats with the tread pattern. It is an art for the designer to minimize the appearance of scalloping with tread and carcass design.
This scrubbing affects the way the tire handles. New front tire feels neutral but near end of life it has to be forced into turns, or wants to fall into turns at low speed, different at high speed? Is all in how the tread developed its scallops.
Having said all that, a Bridgestone T31GT usually running 39 PSI is the only FJR front tire which I thought rode as good at 9500 miles as it did new. Went through a couple T30 Evo not-GT after that and didn't get 5000 miles from either and was glad to replace then. Cant get T31GT so I mounted a T32GT. So far so good.