Tyre question.

[sjb993]

I have read many times that non run flat tyres provide a smoother and quieter ride than run flats. I can understand the smoother ride, because the sidewalls on non run flats are more compliant over bumps. What I don’t understand is why, since non run flats and run flats have the same profiles, and hence the same contact area with the road surface, non run flats are quieter than run flats.

Can anyone explain why?

Thanks.

[Sim89]

RFTs don't 'generate' more noise than non RFTs as such. The result of the stiffer sidewall and other construction elements allows for more vibration (which is all noise is) and harshness to be transmitted into the cabin, along with a less compliant ride. I find them very unpleasant.

[sjb993]

Thanks for the explanation.

[Mr Tidy]

Bear in mind though that some run-flats are much better than others!

I've never had RFs and NRFs on the same car so no direct comparison sadly, but the 17" Pirelli P Zero RFs I had on my 1 Series with M-Sport suspension were way more comfortable than the 18" Bridgestone Potenza RFs I had on my Z4 that also had M-Sport suspension.

And the 17" Continental RFs on my 3 Series SE aren't too bad so I've lived with them for the sake of practicality as it is my daily.

[mekondelta]

Mr Tidy said:

Bear in mind though that some run-flats are much better than others!

I've never had RFs and NRFs on the same car so no direct comparison sadly, but the 17" Pirelli P Zero RFs I had on my 1 Series with M-Sport suspension were way more comfortable than the 18" Bridgestone Potenza RFs I had on my Z4 that also had M-Sport suspension.

And the 17" Continental RFs on my 3 Series SE aren't too bad so I've lived with them for the sake of practicality as it is my daily.

+1 for PZero RFTs!

[Pica-Pica]

mekondelta said:

Mr Tidy said:

Bear in mind though that some run-flats are much better than others!

I've never had RFs and NRFs on the same car so no direct comparison sadly, but the 17" Pirelli P Zero RFs I had on my 1 Series with M-Sport suspension were way more comfortable than the 18" Bridgestone Potenza RFs I had on my Z4 that also had M-Sport suspension.

And the 17" Continental RFs on my 3 Series SE aren't too bad so I've lived with them for the sake of practicality as it is my daily.

+1 for PZero RFTs!

Minus 1 for Pirelli RFTs.
I know I changed size but 18” Goodyear EfficientGrip, were much quieter than 19” Pirelli Pzero.

[NicheMonkey]

My BMW 220i came with Michelin Pilot Sport 4 ZP's and they seem very good if not as good as the non run flat version.