Summer tires on potholed roads

[machareus]

Hi folks,

Wanted to share my experience with tire choice.

I live in the NYC area and the roads here are awful. Having switched from 16" rims to 18" rims on my 08 E90 which was on run flats at the time, the car ended up in the shop on a (no exaggeration) weekly basis because I kept getting flats from normal road conditions (e.g., lane-wide resurfacing bumps on the highway). At that point I swore off run flats and also chose to increase sidewall height on go flat replacements.

When I was ordering summer tires for the 15 F06 CP that I purchased last November with 433M rims and stock suspension, I wanted to go from stock 295/30-20 (27" tire height) rears to 305/35-20 (28.4" tire height). 305 for better grip, and 35 for rough roads.

I searched a lot on these forums to see if any other users have installed tires that tall and no one seemed to have the exact tire setup I was looking for. The closest I found was 325/30-21 (28.7" tire height) that 2007 to 2016 M6 Cab put on his F12. He had reported no fitment issues other than slight rub on the wheel well liner which was resolved by his dealer.

That gave me some confidence to order 305/30-20s for the back and went with 265/40-20s for the front to match rolling diameter most closely. Went with MPS4S and was able to get premium touch for both front and rear.

I'm happy to report that so far I've experienced no rubbing in the rear.

The fronts do experience a SLIGHT bit of rub against a small protrusion towards the bottom of the rear of each wheel well liner. The protrusion is small, so the rub only happens when turning the wheels at a slight angle (one half steering wheel rotation in either direction). I haven't seen any evidence of marking on the tires, but I can hear the contact. That amount of wheel turn typically only happens at low speed when turning a full 90 degrees. Will be taking the car back to my local shop to see if they can adjust the wheel well liner so the small amount of rub gets eliminated entirely (which seems to be what 2007 to 2016 M6 Cab's dealer did as well).

I know a lot or most of you guys prefer 21 inch rims with a drop. I've seen comments on the forum the whole point of a carbon roof is to lower center of gravity and taller sidewalls raise it. Plus the extra rubber adds more unsprung weight. And some of you might think that it just looks bad. All valid reasons to not do what I did...on proper roads. Alas, I cannot fix the potholes and bad road repairs where I live and I cannot move somewhere where the towns fix them properly.

Here are some pictures before I had a chance to get it washed and get the tires shined up. Happy to hear your (hopefully respectful ) opinions. I like it

[JDMSteven]

I'm from NYC, but live in FL now. I was actually up in the city last weekend and man, it reminded me how much I hate the roads and infrastructure there LOL. That actually looks like it fits spot on, doesn't look weird in the slightest. I agree with the 21" wheel thing, I think that looks outrageous and skinny rubber bands are not my style. I have stock tire sizes and stock dimension wheels on H&R Springs and that's plenty good enough for me. My carbon lip only sits like 3.5" off the ground from its lowest point.

[machareus]

Originally Posted by JDMSteven

I'm from NYC, but live in FL now. I was actually up in the city last weekend and man, it reminded me how much I hate the roads and infrastructure there LOL. That actually looks like it fits spot on, doesn't look weird in the slightest. I agree with the 21" wheel thing, I think that looks outrageous and skinny rubber bands are not my style. I have stock tire sizes and stock dimension wheels on H&R Springs and that's plenty good enough for me. My carbon lip only sits like 3.5" off the ground from its lowest point.

Thanks for the reply! I've seen your car on the forums and it looks mean!

I typically find myself preferring the proportions of the GC to the coupe on the M6 (I have the opposite opinion on the M8), but I think you found the right setup to make the coupe look really svelte.

Black grilles and carbon mirror caps are on my list of changes to make. I already have the grilles that I bought from Flo, but I learned that a prior owner of my car did a poor job of fixing up the front bumper after a minor accident and my dealer recommended not installing the replacement grilles because they may get damaged.

Are your mirror caps OEM or after market?

Front lip might go on the list as well, but my wife drives this car sometimes when the E90 is in the shop (at least until we swap the E90 with an X7 [or XB7 if I can find one at the right price ]) and she gets traumatized from scraping the rubber lip. So she would have a heart attack if she scraped a carbon one. She loves driving the car though which I think is awesome.

[JDMSteven]

Originally Posted by machareus

Thanks for the reply! I've seen your car on the forums and it looks mean!

I typically find myself preferring the proportions of the GC to the coupe on the M6 (I have the opposite opinion on the M8), but I think you found the right setup to make the coupe look really svelte.

Black grilles and carbon mirror caps are on my list of changes to make. I already have the grilles that I bought from Flo, but I learned that a prior owner of my car did a poor job of fixing up the front bumper after a minor accident and my dealer recommended not installing the replacement grilles because they may get damaged.

Are your mirror caps OEM or after market?

Front lip might go on the list as well, but my wife drives this car sometimes when the E90 is in the shop (at least until we swap the E90 with an X7 [or XB7 if I can find one at the right price ]) and she gets traumatized from scraping the rubber lip. So she would have a heart attack if she scraped a carbon one. She loves driving the car though which I think is awesome.

I actually don't know what brand the caps nor grille are, off brands possibly but the fit and finish are decent, picked up used from a local owner who was going back to stock to trade his in

[machareus]

Originally Posted by JDMSteven

I actually don't know what brand the caps nor grille are, off brands possibly but the fit and finish are decent, picked up used from a local owner who was going back to stock to trade his in

They look nice! I'm currently strongly considering RW Carbon mirror caps....$400 for a pair vs. $575 for a single mirror OEM. People on the forums have said good things about RW Carbon but I need to do more research.