The Roadster wires are wide, and having watched the fitter change mine, it's very easy for the tyre bead to scrape the sealant. All four of mine were slightly damaged, despite the fitter being experienced and an old friend. But I don't take the Morgan for tyre changes, I take the wheels off. Just in case.


DaveW
'05 Red Roadster S1
'16 Yellow (Not the only) Narrow AR GDI Plus 4