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Bought 2nd hand with good tread.
Installed by my local bike shop, all looked good.
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Lucky escape......my guess is the bead has separated after being inflated well above 50psi to pop the beads onto the rims.
I hope the bike shop reported the tyre failure up the line to Pirelli in case it was a batch problem, but I suspect it might have been their error at installation.
I have run Michelin's for decades, all the PR series, and the R5, but haven't had the opportunity to go R6 yet (out of stock when I wanted to change).
I run 35psi Front & 37psi Rear as advised by Michelin tyre rep for solo (36f 40r dual) and never get less than 20,000kms a set or have any slips in heavy wet & cold conditions. I don't recommend 42/42psi, but some do.....maybe it suits their climate.
Know what pressures the MGp riders use for their 340kph 45minute flat out race battles?...... 24psiF & 26psiR......I kid you 'knot'

Disclaimer.......you choose the right psi for your part of the world and riding style - if in doubt, ask a dedicated independent tyre shop, not a Honda agent who must follow company advice covering the whole planet for legal/contractual reasons

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I'm also a 45+ year rider with 18 bikes through my hands and many more test rides

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