[greenivychi]

I am coming off owning for 5.5yrs a Golf R where I went from the 19 stock to 18in to then 17in all with the goal of trying to get better pothole protection. Unfortunately even with the 17s it wasn't enough

I was hoping to get some advice of a setup that would offer good protection from potholes for a 2021 M240ix.

Tirerack is showing the most agressive as 225 45 17s,.

[TrboMike]

If that is the goal you want:
-as wide of a tire as possible 255 front and either same rear or wider. My cars with wide tires go over most potholes in the NY/NJ area. My miata with my skinny snows fall into potholes and can crack suspension
-as small a diameter rim as possible, but that you already know
-a lighter wheel will cause less force when hitting a pothole, but most lighter wheels are also more delicate. A heavier wheel can take more beating but at the same time the unsprung weight will make the same pothole hit come with more force. So you want a light but tough wheel, which usually means exotic and expensive like flowed, forged, and or multi piece.
-a rim slightly small in width to the tire. When the wheel holds the tire sidewall perfectly vertical more force of a pothole goes up into the wheel and into your suspension. If the wheel is slightly more narrow you get more tire sidewall flex and more pothole absorption.
-not runflat tires, sidewall very stiff and transfer too much force
-tire with softer sidewall than most to absorb more impact
-softer springs, softer shocks. The more your suspension can absorb from the pothole hit the less force will go into the tire, wheels, suspension, chassis.
-I've heard some people say tires with "rim protection" which is extra rubber along the rim lip help protect the wheel from bending or cracking, but I've heard others say it makes the sidewall stiffer and puts more impact into the suspension. So I'd ask tirerack about that one for their opinion.

This is all OPPOSITE to performance tho. You're trading performance for softness to absorb pothole hits.

Yes I've lived in NYC and north NJ all my life. We know potholes.

[LanceM26]

I run 245/40/18 square and find that I have enough sidewall. You can find a 17inch wheel and have an even thicker sidewall.

[davehoff]

My pothole set up on my f23 is 17" BBS SX
Wheels with 225 45 DWS Cont
Non run flats are a must I live outside of NYC
So far so good

[bensanford]

I just switched to my winter tires, 225/45 R17's all around, and wondering about tire pressure.

My summer tires are 225/40ZR18 front, and 245/35ZR18 rear, with BMW recommended pressure on door marked as 32 front and 38 rear.

With the 17" tires, I'm thinking of maybe 30 in front and 36 in rear, but maybe I need to stay with higher to better deal with potholes.

[Jnat]

Originally Posted by LanceM26

I run 245/40/18 square and find that I have enough sidewall. You can find a 17inch wheel and have an even thicker sidewall.

How bad was the impact on acceleration with the taller tire (or not noticeable)? I'm sure it looks fantastic...