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2016 440i convertible
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Discussion Starter #1
I bought a 2016 440i convertible at the weekend and today, after laying on my stomach several times, figured out the previous owner had mixed his tyres. What domyou think of:

Fronts - Potenza RF near side, Pilot Sport 3 off side (is it a RF? I can’t find any mention on the side wall).
Rears - Both Potenza’s one 93Y the other 89Y, and both nearly 4 years old.

I’d appreciate some advice on whether the above is ok/dodgy/dangerous. I’m not too happy about having different tyres on the front. Surely that can’t be good for wet weather braking?
I’ve also noticed a slight directional instability at motorway speeds.

Let’s say I change the fronts as a pair, can I go with non-run flats and keep the run flat Potenza’s on the back?

Incidentally, the tyre noise above 85mph is dreadful. I have just chopped in a 2008 Mercedes SL63 and it was no where near as noisy.

Thanks in advance for helping me sort this conundrum out. Apologies if I’ve raised familiar topics, this is my first post.
 

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At best I'd say it's dodgy - not sure it could be classed as dangerous I'd rather have quality mixed tyres than budget ditch-finders (I do break into a sweat though at the thought of non-matching tyres 😓😅)

But what ever - bite the bullet swap all 4 go non-runflat and enjoy the comfort or stay with runflat and enjoy the peace of mind
If you've blown all your budget on buying the car look at something like Uniroyal Rainsport 3, they are great value at www.camskill.co.uk and are a fantastic wet weather tyre (especially now summer is over ;))
They aren't the quietest or last the longest but boy do they grip

Another budget option is eBay part worns not everyones cup of PG but you can get nearly new, top of the range tyres for ditchfinder money - I put a full set of 20" Michelin Pilot Sport 4S on mine for less than £350 fitted (£800+ RRP)

What ever you decide enjoy the car and welcome to BF!

:)
 

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2016 440i convertible
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Discussion Starter #3
Thanks Forsh for input.
As an ex-motorcyclist I too can get pretty ‘religious’ about my tyres, so with some unspent budget still left in my pocket I think I’ll take your advice and buy 4 non run flats. Which ones for all round UK driving and occasional playtime I’m not sure. There are some reviews I’ll need to read....
 

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Stick with anything with 'A' rated wet grip - dry grip practically goes without saying for road use
Rainsport 3s have been updated with 5's now - if the new ones are quieter they'll be fab

When I had my 18's on I replaced my worn out Rainsport rears with Goodyear Eagle F1 Asymmetrics and was amazed at how much quieter they were - I had to turn the radio speed volume thing down!

I'm a big Michelin fan though - 4S FTW!

and always worth checking Camskills prices if you have a trusted local tyre fitter

:)
 

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There is a new rainsport 5 out now that is supposed to last longer.
I have had 2 set's of the rainsport 3's and love them so looking forward to trying the 5 out but that will be some time yet.
 

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2016 440i convertible
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Discussion Starter #6
Does anyone know whether the Michelin Pilot Sport 3 is a Run Flat?

I can’t find anything on the side wall other than ‘Extra Load’, which suggests to me it’s a regular tyre.
 

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Discussion Starter #8
Thanks Darrencharlwood.
That means the dealer sold me a car with a run flat on front NS, and a non-run flat on front OS!

Is that legal? It can’t be good for handling and braking?
 

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As with any tyres - as long as they are correctly inflated then I don't see why there would be any noticeable difference

In theory you could have a Michelin Cup 2 on one side and an Autogreen SuperSportChaser SSC5 (actual tyre!) on the other and still fly through an MOT - straight in to the ditch on the other side

Not something I could live with but it is what it is

:)
 

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That's a fairly stunning combo of mixed RFT/non RFT and brands/weight loadings. It's almost as though someone had a thing about trying get as many different varieties on it as possible!

As Forsh says, MOT fine as long as tread OK. And frankly probably fine in ordinary driving. But a lot less funny in extremis - eg emergency braking in the wet where there will be divergent levels of grip that could destabilise the car. And goodness only knows what it would do the handling if driven hard - I dare say it could make it quite unpredictable, especially in the wet.

I'm not sure about illegal, but it's certainly very bad practice and ought to be a source of both concern and embarrassment to a reputable dealer - especially the mix across axles and RFT/non RFT.
 

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Discussion Starter #11
Thanks for the advice. I just got back from a tyre fitting shop and apparently the “ZP” discretely written on the tyre stands, in Michelin speak, for ‘Zero Pressure’, which means this particular Pilot Sport 3 is a run flat!

That said, I agree with Evog’s comments about wet braking performance, etc. So I’m not happy. The Dealership who sold me the car (DesirableCars.com in Leicester) feel the situation is now resolved, as all tyres on the car are RF’s.

But I feel uncomfortable with 2 different makes of tyre & 2 different tread patterns/compounds on the front axle where most of the breaking force goes, so I’m going to bite the bullet and buy 4 new non-run flats. (Might as well take this opportunity to switch). What tyre to buy is the subject of the new post!

Thanks for everyone’s help :)
 
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