Is it normal for runflats to lose air more than regualr tyres?

I have a 2017 BMW 4 Series with 225/40 R19 tyres on the front and 255/35 R19 tyres on the rear (runflats). Over a two month period, both rear tyres have lost 0.3 bar and the front tyres 0.1 bar. The BMW dealer states this is not unusual with runflat tyres. I would appreciate your view on whether this is normal please.

Asked on 18 August 2017 by

Answered by Honest John
It's not the fact that they are runflats. It's the extremely low profile of the tyres that means the rimseals take a greater pounding.
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