Has anyone had experience building their own spare for the F30 / F31? I’m looking to build a spare for my 2016 F31 328ix. The catch is that with the M Sport calipers, the 17” rim most use will not work. I’ve read that the 18” spare alloy wheel (36116796147) for the F01/F02 & F25, will work if fitted with a 145/70 R18 tire. I can only find two manufacturers for this tire size, Maxxis and Yokohama. Never had any experience with either of these brands, but then again, this is a spare, so maybe that’s a good thing. Even though I have the mobility kit, I would rather a real spare for longer road trips.
Don't have your car so no direct experience - I was able to just buy a kit from ECS; however, using this: https://www.rimsntires.com/specspro.jsp comparing 225/45r18 to 145/70r18, they're essentially the same rolling diameter, 25.9" v 26", so you're good there. I think the spare tire brand I have is a continental, but presumably you should be ok with either - Yokohama is a major tire manufacturer; I guess Maxxis is newer to the scene, I've seen their ads over the last several years. Tire Rack carries the Yokohama in that size. Your unknown is the caliper clearance, but fwiw the 17" BMW spare wheel clears the M-Sport calipers on my E92 335is. https://www.tirerack.com/tires/Tire...8&rearWidth=255/&rearRatio=40&rearDiameter=17 (input your own zip) https://www.ecstuning.com/b-genuine-bmw-parts/emergency-wheel-priced-each/36116796147/ ECS presumably could piece together the items in their kits - a lug wrench, folding collapsible wheel chock, and the appropriate jack for your model (mine's a scissor jack, not sure what yours may be). I got a bag to hold it all too, but that turned out to be unwieldy - I stow the jack etc in the storage trays as packed away as possible, jam the spare forward and run some ratchet straps over it to keep it in place using the trunk luggage tie down attachment bars.
Thank you for the info. I should have read the CCA Classifieds before creating the thread Same day, another member posted an F30 spare that will fit over the blue M Sport calipers. Needless to say, I jumped on it. Yes it’s a steel wheel instead of an alloy, and I need to use a centering ring, but the price was right. Now just need to pickup a jack that will work on my car.