F15 staggered wheel setup clarification

[RockDriver]

I'm looking at F15s, but currently a bit frustrated with all the different rim/tyre sizes. Bottom line is I need all season tyre set and since it's the F15 (no spare tyre) - they also have to be run flat.

There's a good selection of tyres for the standard square 18 inch rim setup. But I'm currently considering this one: https://www.autotrader.co.uk/car-details/202212242...

And this sucker seems to have the 19 inch staggered setup, 255/50 R19 front and 285/45 R19 back, from what I understand (correct me if I'm wrong). No 285/45 R19 all season run flat tyres are available in UK.

Any suggestions for this situation? An alternative would be to go with all season conventional non-run flat tires, but then I'd need the spare wheel. I've been tumbling down that particular rabbit hole for a while, and it seems that the spare wheels being sold (in UK at least) may not be quite the right circumference, which could apparently upset the Xdrive.

Appreciate any ideas.

[RockDriver]

EmailAddress said:

Bin that idea and the world is your oyster.

I'd be happy to do so, but as I said - the spare wheel question is not entirely clear. I guess I could just say screw it and go without, relying on AA not abandoning me in some no man's land. I've already been stuck with a flat one beautiful freezing snowy night and it was the opposite of having fun. I did have the spare then too, but had to limp a few hundred meters out of dangerous traffic zone and that was enough to kill the non-run flat tire, hence my interest in run flats.

[bigdom]

As it doesn't have the 3rd row of seats, you can fit a spare tyre kit in the hole. It's to get you home, so unlikely to do any damage in that time, especially as BMW sold a kit.

I have spare tyre kit in an older BMW as it has the space, others just have plugs and sealant in the boot, if the AA is going to take too long to get there. The missus has a Golf with factory pump and goo.

When was the last time you had a puncture? I haven't had one for 16 years. The day I did was 1st day driving to a new job.

[RockDriver]

bigdom said:

As it doesn't have the 3rd row of seats, you can fit a spare tyre kit in the hole. It's to get you home, so unlikely to do any damage in that time, especially as BMW sold a kit.

I have spare tyre kit in an older BMW as it has the space, others just have plugs and sealant in the boot, if the AA is going to take too long to get there. The missus has a Golf with factory pump and goo.

When was the last time you had a puncture? I haven't had one for 16 years. The day I did was 1st day driving to a new job.

Yeah, I'm only looking at 5 seaters, so the space for possible spare wheel is there among other reasons. I'd had to find a way to fasten it, so it wouldn't bang around loose. I don't know, I found these: https://www.thewheelshop.co.uk/product-category/sp... So I guess this means if I get the X5 with 19 inch wheels, I should also get the 19 spare wheel.

Last flat I had was like 7 years ago and of course the weather was extra ѕhit as luck would have it. I don't know, maybe I am being overly cautious. There's a much better selection of non run-flat tyres too. Just wanted to hear y'all's opinions on this.

By the way, would the choice of non run flat tyres impact the TPMS in any way? I understand that F15 uses circumference detection method instead of the pressure sensors? I drove an F15 recently and it suddenly threw a low pressure warning on one of the tyres, so I stopped and checked the pressure on the indicated tyre - it was fine.

[E63eeeeee...]

Have a look at the widths each side? So 275/45 or 295/45 (check your rim widths to make sure you're still in spec for the wheels whichever way you go).

My E Class came to me with 10mm wider rears than standard, I didn't even notice until I came to get them changed. I suspect that was for similar availability reasons.

[bigdom]

RockDriver said:

Yeah, I'm only looking at 5 seaters, so the space for possible spare wheel is there among other reasons. I'd had to find a way to fasten it, so it wouldn't bang around loose. I don't know, I found these: https://www.thewheelshop.co.uk/product-category/sp... So I guess this means if I get the X5 with 19 inch wheels, I should also get the 19 spare wheel.

Last flat I had was like 7 years ago and of course the weather was extra ?hit as luck would have it. I don't know, maybe I am being overly cautious. There's a much better selection of non run-flat tyres too. Just wanted to hear y'all's opinions on this.

By the way, would the choice of non run flat tyres impact the TPMS in any way? I understand that F15 uses circumference detection method instead of the pressure sensors? I drove an F15 recently and it suddenly threw a low pressure warning on one of the tyres, so I stopped and checked the pressure on the indicated tyre - it was fine.

The 18 inch one will be the correct size, it will just have a taller side wall, unless there's a specific brake package issue, like M50d.

Having had a runflat flat, personally I wouldn't want to drive on one again. I know tyres have improved a bit, but I prefer standard tyres. I've run Michelin PS3/4/5's on various cars with no issues.

TPMS, could just be that the valve isn't seated correctly in the wheel and leaking small amounts, spraying a light mix of washing up liquid & water will quickly show bubbles.