Cupping Tires

[Levisp]

I believe that PR4GT's were tested by BMW on the RT. It is an OEM tyre fitment. I would therefore suggest that the recommended tyre pressures given in the manual and by Michelin are correct. 36 / 42 psi

[guest2360]

My intended swap to PR4s got cancelled this morning.  Looking at the GS forum it looks more than just bad luck on punctures.  So back to Z8s for me next month. They were factory fit on my 2 1600s and my LC.  Never had an issue with them in the last 5 years and if they coped with 1600s they must be very lightly stressed on an RT.

[richardbd]

My intended swap to PR4s got cancelled this morning.  Looking at the GS forum it looks more than just bad luck on punctures.  So back to Z8s for me next month. They were factory fit on my 2 1600s and my LC.  Never had an issue with them in the last 5 years and if they coped with 1600s they must be very lightly stressed on an RT.

You know me RTman - in my view, you're the guru - but on this one I disagree.  You're being too influenced by what three men, two dogs and a loony on UKGSer have to say...


I must have ridden 50k miles on PR3s, PR4s and PR4GTs - I recall two punctures and a (recent) dodgy tyre.  I rode 400 miles on Z8s and had two punctures.  Draw your own conclusions but I'm sticking to the tyres that feel the best when I'm enjoying the ride...

[guest2360]

I appreciate your comments.  But the deed is done, they've gone back.  Maybe next time.


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[ggoldfogel]

I believe tire cupping is a factor of weight. Operating at recommended pressures I consistently get some degree of cupping with Michelin PR3 and PR4s on Yamaha FJR and not with lighter Honda NC 700. My RT is new. And lovely.

[Levisp]

I believe tire cupping is a factor of weight. Operating at recommended pressures I consistently get some degree of cupping with Michelin PR3 and PR4s on Yamaha FJR and not with lighter Honda NC 700. My RT is new. And lovely.

Well maybe but I think its more down to suspension and geometry. My Pan ST1300 weighs more than your FJR and the tyres have worn very evenly with no cupping. I think its a complex subject.

[Jriffe108]

Up your pressure, I run 42 Front and Rear. PR4 GT's. All front tires will cup with mileage, it's a fact. It is exacerbated with lower pressures. The PR4 is an excellent all season tire, IMO. I run an authority bike and it is the only tire approved for use. The GT version is stiffer so it is somewhat run flat capable for getting off the road in the event of failure. I averaged 6k miles on rear before picking up a nail on last three sets, and front tire was good for 12k miles before center tread bar was up and edges cupped. Mine you, this is on an authority bike that sees a lot of WOT from standstill, extremely hard braking, and lots of hard lean angles at speed and low speed parking lot cone work.