finski

So I drive an '04 545i with the sport package and the 124 rims. The OEM tires are Bridgestone RE050A RFT (245/40R18 front and 275/35R18 rear). Sure they grip, but otherwise I hate them with a passion. Rough and noisy as heck. Went from sounding like a pick up truck with knobbies to a near silent luxo-boat when I switched out to my winter Micheline Alpins (also a run flat tire)on Borbets. Now apparently my alignment is perhaps out a bit becuase the tech doing the tire switch noted some very slight feathering on the edges of the fronts. My non-BMW service guy (who also owns 3 BMWs himself) says shed the run flats, reduce unsprung weight and enjoy all round better performance and handling and much quieter driving.

This thread has probably been done before, but new tire intro's seem to happen fast and furious so I would appreciate an update and experienced opinions (I have talked to both tire rack and Bavauto a couple of times and I sense they may run flavour of the month somewhat). So what say you Guys? Obviously I want a high performance tire, but not totally at the expense of ride and noise. And here in Ontario they have a little deal where they catch you doin' 50 kph over the limit (they call it variously racing and stuntdriving), and they can seize and crush your car, with the added pain of a $10000 fine, so I tend not to test the limits of this beast much. In addition to a highly recommended set of summer shoes, what also do you all do about the spare? Put a spare in the car under the trunk floor or use a temporary refill setup of some kind? Which tires, which 'spare' solution and where best to buy?

BTW, the BMW stealership up here wants around $800 a piece for the OEM tires, they can be had on tirerack for about $1400 the set and currency is currently more or less even. There is very little real security in using runflats up here because mostly nobody stocks them...... I will almost certainly buy mailorder from the US......

uwsc11

I am pondering the same question. I need new rear tires on my 545i Sport and want to switch from run flats to non-run flats. What are you guys driving? What can you recommend? I want performance, stickiness for those fast sweeping corners, but I don't want to buy new rubber every 10K miles, either. Appreciate any input.

Thx

subterFUSE

I switched to Michelin Pilot Sport PS2 tires as soon as my OEM runflats wore out. Have used nothing else ever since. The difference was night vs. day. Better performance and incredibly smooth ride.

finski

I Picked this thread up on a websearch: https://5series.net/forums/topic/966...rom-run-flats/

It covers off the spare tire issue and apparently it's just the Canadians who dont get a spare with the runflats. And of course (inexplicably), the spare costs about double here what it does in the States.

Michelins have always been good to me.

uwsc11

I went to get Michelin PS2 non-run flat put on the rear today. And at first they sold me a pair. Then they come back and told me that they cannot put non-runflat on my rear, if I still have the run flats on the front. Is that true? You can't mix the two.
They were talking about it being a safety issue, since the handling of the car would be different when cornering at spirited driving speeds. The run flats have of course much stiffer side walls than the non-run flats.
Can you guys confirm that, or are they pulling my leg?

luigi524td

I'd say that is is not wise to mix RFTs and nonRFTs because they have very different handling characteristics that could cause an unsafe condition even in normal driving.