[Icarium81]

Just got the above car, not sure how I feel about the run flat tires yet, first car to ever have them, I usually prefer the full size spare in the trunk...
On to my question.
How heavy are the stock 18" rims?
Going to have to buy a set of rims for the winter(CANADIAN in NS) so I might as well buy something lighter right?

Sorry if it's been answered, search isn't working, it hides when the keyboard pops up on cell.

[Icarium81]

Also, for the winter rim, is it possible to go down a size to 17" and put a taller tire on? We get some pretty amazing winter weather and sitting in low profiles is just asking to damage a rim

[VMRWheels]

The 17's shouldn't be a problem on that car with a 225/50/17 tire, but you should be able to get away with 18's as well with a 225/45/18 tire.

Not too sure on the weight of the stock 18's.

[chowser51]

Which stock wheel? You can look up the specs.

My car came with the 18” 400m wheels. I got 17” winter wheels and tires. Sold the 18s and got 19s for summer.

All goflat tires. I hate runflats. I even had the Bridgestone Driveguards which were better than the Contis I had on my last BMW. I keep plugs and a compressor in the trunk. And a bottle of slime for emergencies if I can’t plug it.

[thatBimmerBloke]

I've the 18" 400M wheels, the rims are about 26lbs each, they have the s#!tty Continental run flats on them, 225x45. Have ordered APEX ARC-8 18x8.5 and will be putting MPSS 255x40 on them, should be here in a couple of weeks. ARC-8 is about 18.5lbs each, will be cutting down a lot of weight I've seen a lot of threads mentioning a great improvement in ride and noise levels after switching to non-run-flats.

[Icarium81]

Thanks, that is exactly what I was looking for. I'll be looking for some ultralight rims to switch too.

[thatBimmerBloke]

Originally Posted by Icarium81

Thanks, that is exactly what I was looking for. I'll be looking for some ultralight rims to switch too.

Look for flow-formed/flow-forged wheels, they are somewhere between cast and forged wheels, should be around 20lbs. Each lb reduced will result in atleast 3lbs reduction in rotational mass, some even claim it's 1:10 ratio but that seems a bit extreme

[alohasurftoad]

Originally Posted by Icarium81

Going to have to buy a set of rims for the winter(CANADIAN in NS) so I might as well buy something lighter right?

Originally Posted by Icarium81

Also, for the winter rim, is it possible to go down a size to 17" and put a taller tire on? We get some pretty amazing winter weather and sitting in low profiles is just asking to damage a rim

i understand your feelings on going down to a lighter aftermarket 17" and higher profile tires for winter, however during winter is NOT when you'll realize it's performance benefits.

just find some OEM style 393(17"), put winter tires on them and put summer tires on your 400M that you have now.

personally, what i'd do is use the OEM 18" 400M for winter on either 225/45/18 or 235/45/18 sized winter tires and buy a set of flow formed(aka rotary forged) aftermarket 18"(or maybe even 19") with summer tires. your money is better spent and its performance gains are better realized doing it this way, imo. in short, if you are going aftermarket make it your summers...

FYI if you have big brakes(M-sport blue) 17" will not fit

[Icarium81]

Not so concerned with performance gains in the winter, just wanted the 17s for the taller tire in the winter. haven't checked but I doubt I'd be able to find any OEM 17s for less than aftermarket 17s.

No big brakes