I just had Yoko S-lines (205-45-17) installed on Mini 8 spoke rims. I knew they would ride harsher than the 15" wheels and tires. I ran the 15s at 30 psi and got a reasonable ride. Yokos are not run flats. Thanx in advance for your assistance.

Jim

 

The recommended pressure for 205/45-17 on the MINI varies with the load and whether you will be exceeding 100 mph (Autobahn). If you are driving with just yourself and a passenger under 100 mph, you can go with 36 psi. With a full load and/or 100+ mph, 38 psi is recommended.

If you go with much less, you'll risk trashing the weels on potholes, wear the edges of the tread more than the center, and could risk breaking the seal between wheel and tire when cornering hard. Handlling would also suck.

Oh yea, and under-inflated tires tend to overheat, which could lead to weakening their internal structure.

You just had to get bigger wheels...

 

Robin,

Thanks for your input. You are absolutely right on all counts. I usually run a couple of PSI below manufacturers recommended pressure and have never experienced any issues. Maybe I should look into aftermarket shocks to try to improve ride quality. I just can't believe how harsh a base cooper rides. I'd expect it on an "S" with 17" run-flats, but man, my JAC was harsh with the stock 15" contis. But, I just love the baby steam roller look that the 17s give the car.

Also, kudos on the custom speaker enclosure-way cool!

Motor safe

Jim

 

Mine rode like a caddy on the 15" compared to the 17" & 18" sets.

 

38 psi is what I run. I went from 16" rft's to 17" non-rft's and am very pleased with ride....smoother and quieter than OEM.