z4 runflat or not runflat when choosing tyres

[steve_bmw]

i have a z4 and its on 255/35/18 rear and 225/40/18 up front. Potenza RE050.
on the motorway and smooth roads the ride comfort is great, but when using the car around town i have noticed the ride is a bit harsh.

i know the sidewalls on the tyres are small but would using non runflats smooth out the bumps better?

would i notice a difference by swapping to non runflats or am a wasting my time and should stick to the same tyres???

cheers

steve

[Sticks.]

Consensus seems to be it's worthwhile. Worth doing a search on PH and http://www.z4-forum.com/forum/

I didn't change mine for a long time but was glad when I did, even if just for the loss of tramlining. Car feels like you would expect now.

Note a dealer will deduct the price of a new set of rfts if you trade in with non-rfts (or less than 5mm afaik) and you need to notify your ins co (who will prob not be interested, but...).

[griff7]

I bought a second set of replica wheels and tyres for my 330d m sport touring off ebay just to get away from runflats and they cost less than a set of runflats and now the tyres are less than half the price and now it is like driving a different car, and when i come to sell it i will just put the original wheels and tyres on.
And my m3 does not run run flats anyway.

[ShiDevil]

Hi,

Seriously...change the bloody things. The general concensus is it's night and day in terms of difference. I swapped from Runflats to Eagle F1's and there is a massive difference. No tramlining, no hard ride etc. Tbh Runflats are dangerous imo.

If you posted this on the Z4Forum, I guarantee 90% of people would say swap.

Options for tyres, are Eagle F1's or Falken 452s.

Have fun

Steve

[Windymiller]

My 3.0 had the sport suspension and the 18" ellipsoid alloys and it came with brand new tyres so I was loathe to chuck 'em in the bin...

I read all the posts about the difference runflats made, but thought people were making more of it...

However, when I flung the wheels in for a refurb, I pulled some 18's off my track car with standard tyres on... the difference truly was amazing! Not just the bump and crash, but I could hold the bugger sideways much easier as I could feel it break away gradually, then bring it back in line smoothly, whereas with the RFTs it would snap like a bugger.

Do it!

[steve_bmw]

cheers for all the info guys, i will be swapping to non runfalt tyres!

everything you say and i have read about is right, mine tramlines realy bad, crashy ride, and i feel there is NO feedback from the tyre, not good, i like to feel the tyre grip, then move about to let you know when your on the limit, with the rft's i feel that they would just loose grip in an instant without any warning.

thanks guys!

[ShiDevil]

Good Choice

[deaglecat]

just make sure you do all 4... not just the rears. BMW advised me to not mix RFT and non-RFT but were willing to swap all 4 existing to non-RFTs.