I only use 180zr55/17 rears now with 2 ply re-enforced carcass's,, such as the Pirelli Angel GT/GT2 A-spec,,, or the Metzeler Road-tech 01 HWM,,, always at 42psi. The only front tire I have found that runs well for me is the 120zr70/18 Metzeler Z8 M-spec. But I recently learned that the Z8 model is being discontinued in favor of the newer Road-tech line,,, and they don't have a front tire in our size,, just as the newer Angel GT2 line does not. I think that selection of 18" front tires is shrinking from many manufacturers,, as it is no longer a popular size across more current bikes. I bought myself 2 spare front Z8's last month,, and that should last me till the end of the 2021 season. And that only left 2 of those tires in stock at the warehouse. So that will give me some time to figure out what is going on the front of my bike, after those are done. Cheers,,, CAt'