I keep getting bulges in the sidewalls of my run flat tyres?

My BMW 330d developed a bulge on its front 225/40R19 89Y run flat tyre earlier this year, requiring a tyre change. In June I hit a pothole which resulted in a bulge on both near side tyres. They are Bridgestone Potenza tyres. Any advice would be welcome.

Asked on 30 July 2019 by Roland Jarrett

Answered by Honest John
Your problem is that the tyres are 225/40 and that sort of profile is too low to withstand the sort of potholes you are encountering. The only answer is smaller wheels and deeper profile tyres, but probably better not to go smaller than 18-inch with a 330d.

Check Tyres On The Drive (bit.ly/2ZlEVaR) and Blackcircles.com (bit.ly/2JM6bqG) for sizes and prices and read our Tyre Buying Guide (bit.ly/2wsFHBU)
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