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      11-10-2012, 06:47 AM   #10
metrickid
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Quote:
Originally Posted by NISFAN View Post
So how does a non valid test have any relevance to how quiet or noisy a RFT is in cabin?

All european tyres by law have to have noise ratings listed, and tyres above a certain level are banned. These are drive-by tests and RFT score no higher in these, however, as the connection between tread block and alloy wheel is significantly stiffer on a RFT (I'm using self supporting RFT as that is what BMW use), there is no scientific reason for them to transmit less noise.

RFT bump and thump more than a regular tyre for exactly the same reason, and low profile regular tyres are noiser than high profile again for exactly the same reason, you can't beat the laws of physics.

It is also why they are trying to develop 'auxillary supported' RFT technology as that will enable normal low stiffness sidewalls, giving a quieter/softer ride.
All I was saying was that this wasn't a drive by test. NOTHING else.

Quote:
Originally Posted by HighlandPete View Post
Change the RFT on the BMW, to the same brand 'non RFT' specification and users have found the non RFT version is much quieter.

As said, typically the stiffer tyre does come though with more NVH to the cabin.

The Golf can't be a comparison, as there is no benchmark for NVH, against the BMW. So meaningless, other than a 'drive by' sound level.

HighlandPete
As I stated above. I never said anything else. I just said that this wasn't a drive by test since it clearly states that it is measured in the cabin.
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