Tires for 21" rims!

[RKP-M6]

Hi guys.

So I'm putting 21's on my m6 coupe. But I need tire help. So I'm on stock non CP suspension with a Vorsteiner kit all the way around. I'm not lowering the car because I bought it for my wife and I don't want her scraping. So what size tires do you recommend to fill that gap up the most? I'm going with 21x10.5 in the rear and 21x9 up front. 305/25/21 tires by Michelin are in national back order which makes things tougher as well. Any help is appreciated!!

[TheBlackGT]

Originally Posted by RKP-M6

Hi guys.

So I'm putting 21's on my m6 coupe. But I need tire help. So I'm on stock non CP suspension with a Vorsteiner kit all the way around. I'm not lowering the car because I bought it for my wife and I don't want her scraping. So what size tires do you recommend to fill that gap up the most? I'm going with 21x10.5 in the rear and 21x9 up front. 305/25/21 tires by Michelin are in national back order which makes things tougher as well. Any help is appreciated!!

I've seen a few others on here ( Twitch Massacre ) who run ever wider Pirellis, maybe they can provide some insight.

Good luck.

[Twitch Massacre]

Originally Posted by DINAN_GT

I've seen a few others on here ( Twitch Massacre ) who run ever wider Pirellis, maybe they can provide some insight.

Good luck.

He can go wider than 305 but he would need a wider barrel than what he's planning, 10.5 is how the car is configured stock. He could run an 11 or 11.5 with a 305 or a 12 with a 325. On the other hand if I were the OP I would carefully consider putting 21s on a non lowered car. Not to bash or anything but the car is going to end up looking like a donk Chevy. OP, keep in mind that adding an inch of wheel won't necessarily fill the gap any more than the stock 20s as the tire you'll end up putting on that wheel may very well be a lower profile tire. To eliminate the gap your best bet is lowering. 21s on a lowered M6 are a match made in heaven.

[RKP-M6]

twitch do you ever bottom out going in and out of driveways???

[Majestic]

I have a F13 M6 with the Competition Package + other options..
I'm going with:

ADV.1 ADV05 Track Spec Sl's
21x9.5 up front with a 255/30/21
21x12 in the rear with a 325/25/21
KW Height adjustable spring kit.

Pirelli P-Zero tires although I'm a fan of Michelins

I do have full vorsteiner going on the car and am worried about destroying it with how low the car will sit..

-MMalesic

[RKP-M6]

Originally Posted by Majestic

I have a F13 M6 with the Competition Package + other options..
I'm going with:

ADV.1 ADV05 Track Spec Sl's
21x9.5 up front with a 255/30/21
21x12 in the rear with a 325/25/21
KW Height adjustable spring kit.

Pirelli P-Zero tires although I'm a fan of Michelins

I do have full vorsteiner going on the car and am worried about destroying it with how low the car will sit..

-MMalesic

Yes I'm so worried about that too! Also scared of rock chips. Anyone clear bra there front lip?

[C's Bimmer]

You'll be fine. Just lower the car and enjoy your 21's. You're worrying too much.

[AHI]

FYI I found 265-30-21 & 305-25-21 Vredestein tires today and bought them. There really seems to be nothing else anywhere

[kris1858]

Originally Posted by RKP-M6

Yes I'm so worried about that too! Also scared of rock chips. Anyone clear bra there front lip?

I have the full vorsteiner aero kit and have already scraped (barely) the front lip coming out of a driveway with a slight dip, and my car is NOT lowered. It is up to you if you want to shake hands with danger!
I had "clear bra" installed on the front lip as well as the front of the car. The vorsteiner lip is WELL made with ALOT of clear coat to protect the carbon fiber, so I wouldn't worry about it too much, but the rest of the car WILL get nicked. Heck, I had a very small rock chip within the first 80 miles of driving it! (before I had the paint protectant film installed)

[AllCarbonEverything]

The Vredesteins are the only thing available in those sizes right now. From what I told they dont hold a candle to the PSS especially for the price that they are charging for them but they are good enough to get you through until you can find some PSS,

I was lucky enough to snag a new pair of 305/25s for my rear set but they are virtually gone now. The best thing to do is to place an order with tire rack for them. I even have an order placed for a spare set. They wont charge you until they ship, but it is first come first serve. The more orders placed the more likely michelin will put the tires in production.

As it sits now there is no production scheduled for at least 8 weeks. I wouldnt be suprised if we dont see them for 3 months.

[BimmerGuy25]

I am having this same exact issue, I have called Michelin several times it seems that 305 25 21's are discontinued. I am not a fan of Pirelli so I may just end up pulling the trigger on 325 30 21 Michelin Pilot Super Sports as opposed to Pirelli Pzero 325 25 21. The rims are literally sitting in the garage waiting for rear set tires. Going to decide which route to go with this week.

[AllCarbonEverything]

Originally Posted by BimmerGuy25

I am having this same exact issue, I have called Michelin several times it seems that 305 25 21's are discontinued. I am not a fan of Pirelli so I may just end up pulling the trigger on 325 30 21 Michelin Pilot Super Sports as opposed to Pirelli Pzero 325 25 21. The rims are literally sitting in the garage waiting for rear set tires. Going to decide which route to go with this week.

The overall Tire Diameter on the 325/30's probably wouldnt be a great look.

The Pirellis and Vredesteins I think would be a better option then getting a PSS with specs that arent even close. Of course thats just my opinion.

Ive spoken at length with michelin and tire rack regarding the 305s. From what ive been told, they arent actually discontinued, they just arent in production because the demand isnt high enough compared to the other sizes they need to make. Generally they mentioned this particular size goes into production only once a year, that seems to be why there is such a shortage. If they are in fact discontinued, that would be a bummer.

Id like to do some research to see what other brands made a 21 inch tire thats wide enough for our rims but with the same overall tire diameter, it might just be the vredesteins and pirelli. Another option could be the 295/25/21 PSS. It might be stretching it as far as width but it might be an easier tire to find than the 305s

[BimmerGuy25]

Originally Posted by AllCarbonEverything

The overall Tire Diameter on the 325/30's probably wouldnt be a great look.

The Pirellis and Vredesteins I think would be a better option then getting a PSS with specs that arent even close. Of course thats just my opinion.

Ive spoken at length with michelin and tire rack regarding the 305s. From what ive been told, they arent actually discontinued, they just arent in production because the demand isnt high enough compared to the other sizes they need to make. Generally they mentioned this particular size goes into production only once a year, that seems to be why there is such a shortage. If they are in fact discontinued, that would be a bummer.

Id like to do some research to see what other brands made a 21 inch tire thats wide enough for our rims but with the same overall tire diameter, it might just be the vredesteins and pirelli. Another option could be the 295/25/21 PSS. It might be stretching it as far as width but it might be an easier tire to find than the 305s

I may end up running the 325 25 21 Pirelli, but I really don't want to. Sooner or later I want to do a full tune and need all the traction I could get. I don't think I will have any issues with 325 30 21 PSS. Even considering running 325 30 21 Michelin SC 2's.

I have talked to dealers and even Michelin several times, they kept telling me that tire will no longer be in production. I am hoping that isn't true, but that is coming directly from Michelin.

I had placed an order for 295 25 21, but cancelled it. For that size recommended wheel diameter is 10.5. Mine is 11.5. It would stretch the tire way too much.

[chask]

Originally Posted by BimmerGuy25

I am having this same exact issue, I have called Michelin several times it seems that 305 25 21's are discontinued. I am not a fan of Pirelli so I may just end up pulling the trigger on 325 30 21 Michelin Pilot Super Sports as opposed to Pirelli Pzero 325 25 21. The rims are literally sitting in the garage waiting for rear set tires. Going to decide which route to go with this week.

Originally Posted by AllCarbonEverything

The overall Tire Diameter on the 325/30's probably wouldnt be a great look.

The Pirellis and Vredesteins I think would be a better option then getting a PSS with specs that arent even close. Of course thats just my opinion.

Ive spoken at length with michelin and tire rack regarding the 305s. From what ive been told, they arent actually discontinued, they just arent in production because the demand isnt high enough compared to the other sizes they need to make. Generally they mentioned this particular size goes into production only once a year, that seems to be why there is such a shortage. If they are in fact discontinued, that would be a bummer.

Id like to do some research to see what other brands made a 21 inch tire thats wide enough for our rims but with the same overall tire diameter, it might just be the vredesteins and pirelli. Another option could be the 295/25/21 PSS. It might be stretching it as far as width but it might be an easier tire to find than the 305s

Someone posted here that Michelin has discontinued the Pilot Sport 325/25ZR21. I do not know if it is actually the same demand issue as they have with the 305 or if the 325/25 will no longer be made. I do not see it on the Tire Rack site and Michelin is nowhere near as forthcoming with size and data info as they used to be a couple of years ago.

I am about to post my experience with some 315/35ZR20s on stock rims. It has not been bad, not at all. The reason I mention this is that overall they are the same height as the 325/30ZR21s and roughly the same width. I would say that the only thing I do not like is the sidewalls seem too large. But they do fill up the open part of the fender well quite nicely, much like a lowered car with the 325/25ZR21s do.

The only fitment issue is there is a very slight rub under certain conditions. When going over some rather large undulations in the road (some railroad tracks and the worst of cross street where there is a larger than normal gully formed for drainage (only when it is large, and only the really bad ones) at just the right speed (it does not happen all the time, only when going at certain speeds) the very outside edge of the tire rubs against a part of the fender well lining. What it is hitting is an extended piece of what feels and looks like insulation. It basically very slightly polishes about a 1" strip where the tread rolls over onto the sidewall. It does not appear to be causing any damage, just a little strip where the tire looks new while the rest of the tire is dirtier (like someone had a rag of some tire cleaner and held it there while spinning the tire). It goes back to dirty within a day of normal driving.

This only happens in comfort mode. I have yet to replicate this in sport mode. One reason I have not posted is I have been trying but can't make it happen yet in sport mode. I also have not had the chance to check tire wear to confirm proper inflation pressure for the way I am driving. The tire should have even wear across the tread if properly inflated, though there is a small range where it will wear as evenly as I can measure it so some extra stiffness or comfort can be obtained, though it is very, very slight. I also am waiting on some different sized front tires (out of stock until about now - thanks to the tire companies not making enough tires to have the odd sizes in stock all the time) that should compliment the rears a bit more. They will change things too. I wanted it all to be complete and run in before updating the thread about tires I started some time ago.

EDIT
I almost forgot. As I said it rarely rubs unless I am going over some of the road imperfections in comfort mode. What I forgot to mention is that following. It rarely rubs, hardly at all. During the overwhelming majority of those instances where it did (all but maybe 1 or 2), I had an extra 200-250 pounds at the very back of the trunk and had one or two passengers too (in the front and right rear seats) - in total probably an extra 350-550 pounds in the car with a good part of it at the very back of the car. For it to rub when on my own I would almost have to be going much faster than I would normally take those road problems. And as far as I can remember, none of those instances have been in sport mode. I will add that the extra sidewall seems to have succeeded in making the ride quite a bit more comfortable and I can drive in sport mode with about the same teeth jarring as when in comfort mode with stock tires. BTW - my stock tires were Pirellis and I am switching to Michelin Pilot Sports.
I'll explain a lot more about reasons and results when I get all the data in and post in the other thread.
End of Edit

TwitchMassacre ran into this when he did his conversion to 21" rims. ADV made a slight adjustment in the offset and got the tire to move enough away from this piece for it not to be a problem. TwitchMassacre has lowered his car. I have not lowered mine. If you put the 325/30s on there I do not think you will be able to lower it unless you do something about the offset. Even then it might be a problem - I did not look for this so it might also be okay. I think if lowered the top of your tire would probably disappear behind the quarter panel - my guess is that at an inch lower the point where the very edge of the tread lines end at the sidewall would be even with the fender. As it stands at stock height, mine looks just like TwitchMassacre's - lowered about an inch with 21" rims.

When they put the 315s on my car I did some checking (unfortunately no measuring) and noticed that it looks like there is a good 3/4" if not an inch of clearance the offset could be increased to bring the tire over by about that much. If there is 20 mm there I think a 335/30ZR20 or possibly even a 345/30ZR20 might fit with the right offset. TwitchMassacre was not sure of his rear offset. I've got to have some more work done in just a day or two now and planned to measure this before contacting ADV about some 12" wide 20" rims to see what they can do. My big problem is they are not anywhere near me and doing this remotely would be a pain - thinking of the kind of minor adjustments they did for TwitchMassacre.

Regarding the offending piece under the fender -
You can feel this piece if you stick your hand under the fender well at the joint between the quarter panel and the bumper. There is a horizontal joining line between these two body panels clearly visible standing beside the car. The joint is about 1-2" below the top of the fender opening and roughly at 1 o'clock. If you feel along this line behind the fender, less than an inch in (as I remember - it could be more or less) you will feel a place where this semi-hard insulation material sticks out - actually I am not sure what the material is, but it is not the body. I do not yet know if there is something behind the bulge (like a metal joining piece to hold the fender and rear bumper piece together) or if it is just some extension of the material for some unknown reason. I would also like to add that what I felt seemed to feel like it was molded and not just a happenstance occurrence. It easily could be something created in the forming process of either that insulation (if that is what it is) or its application to the inner fender. I no longer can bend over or get underneath the car to take a good look at this. I'll have to wait until I get to the dealership for some planned service to find out for sure. This will probably happen next week. I had hoped to get that work done and then post about the tires but since you are on the verge of doing something with those tires I went ahead and posted this part here.

Although the two setups (315/35ZR20 and 325/30ZR21)
have the same overall height there will be a difference in the amount of tire showing. Theoretically the sidewalls on the 315-20s is 110 mm and the ones on the 325-21s is 97.5 mm - roughly 12.5 mm. That's half an inch, or half the difference in wheel diameter - what was to be expected. My thread will have some pics in it so you can get an idea what yours would look like.

I think the car has a much nicer rake, making it look a bit more aggressive. From the way the car drives in general (but especially on the highway) I suspect there may be an aerodynamic benefit too. I think the car may be catching the air a bit more, turning the whole top surface into more of a spoiler so to speak. However, it also could just as easily be the wider tires and slightly wider track. Whatever it is, the car feels noticeably more stable on the highway. As the stock wheel/tire setup is about 27" tall, a 28.7" diameter tire/wheel combination on the rear will raise the rear axle by about half the difference (roughly .85", a little under 7/8"). Roughly half the change in height will be below the axle and the other half will be above. The change below the axle will raise the back of the car while the part above the axle just fills the fender well more.

Part of what is going on next week will involve an alignment. I plan on having them check the rear too. I plan to take it somewhere that can if they can't. After a little break in time for the front tires I'll have some reasonable stuff to make an assessment on the change. As of now, the car drives like it is on rails. So far I'd do it again in a heartbeat but there is still more investigation that needs to be done: find out what that interference lining is and what's behind it; check any alignment issues (especially at the rear); with the correct front tires on the car, test the handling (so far it's better but right now it is an odd setup and one that should not be run long term).

[2007 to 2016 M6 Cab]

Originally Posted by RKP-M6

Hi guys.

So I'm putting 21's on my m6 coupe. But I need tire help. So I'm on stock non CP suspension with a Vorsteiner kit all the way around. I'm not lowering the car because I bought it for my wife and I don't want her scraping. So what size tires do you recommend to fill that gap up the most? I'm going with 21x10.5 in the rear and 21x9 up front. 305/25/21 tires by Michelin are in national back order which makes things tougher as well. Any help is appreciated!!

Well, I had the same problem finding rubber ... I had a custom set of rims ordered and delivered just before the car arrived (21 x 9.5 front, 21 x 11.5 rear) from Manu Gill at Aritso Collection ... Could not get the Michelin's in the 21 inch ... ended up with PZero's (245/35ZR21 front and 325/30ZR21 rear) - the car is a 2016 M6 Cab - not lowered, has the carbon fibre front lip ... it looks just right and I do not bottom out on curbs, parking garages etc.

The ride is very nice as well.

They also have BMW's blessing (read approved for BMW vehicles) and are run flats

See for yourself!

There was a slight rub on the rear wheel well liner - all it took was a small plastic body rivet to suck it out of the way - the dealer did this before delivery - no rubbing what so ever

900 km now - 1100 more till we can go catless!!!

[M6-Coupe]

Originally Posted by 2007 to 2016 M6 Cab

Well, I had the same problem finding rubber ... I had a custom set of rims ordered and delivered just before the car arrived (21 x 9.5 front, 21 x 11.5 rear) from Manu Gill at Aritso Collection ... Could not get the Michelin's in the 21 inch ... ended up with PZero's (245/35ZR21 front and 325/30ZR21 rear) - the car is a 2016 M6 Cab - not lowered, has the carbon fibre front lip ... it looks just right and I do not bottom out on curbs, parking garages etc.

The ride is very nice as well.

They also have BMW's blessing (read approved for BMW vehicles) and are run flats

See for yourself!

There was a slight rub on the rear wheel well liner - all it took was a small plastic body rivet to suck it out of the way - the dealer did this before delivery - no rubbing what so ever

900 km now - 1100 more till we can go catless!!!

I'm not sure if 245 front / 325 rear is a good setup (I have a feeling that your will experience under-steering now), but for sure 245 tire on 9.5" means you must be very careful to avoid getting curb rash while your rear rims are protected by wide tires. Please share your driving experience with this setup. Also if you don't mind would you share the rear rims ET?

[Twitch Massacre]

Originally Posted by 2007 to 2016 M6 Cab

Well, I had the same problem finding rubber ... I had a custom set of rims ordered and delivered just before the car arrived (21 x 9.5 front, 21 x 11.5 rear) from Manu Gill at Aritso Collection ... Could not get the Michelin's in the 21 inch ... ended up with PZero's (245/35ZR21 front and 325/30ZR21 rear) - the car is a 2016 M6 Cab - not lowered, has the carbon fibre front lip ... it looks just right and I do not bottom out on curbs, parking garages etc.

The ride is very nice as well.

They also have BMW's blessing (read approved for BMW vehicles) and are run flats

See for yourself!

There was a slight rub on the rear wheel well liner - all it took was a small plastic body rivet to suck it out of the way - the dealer did this before delivery - no rubbing what so ever

900 km now - 1100 more till we can go catless!!!

I must say I agree with M6-Coupe, not to mention the 245 on the 9.5 must be super stretched. I have a 21x9.5 fronts and 21x12 rears. My fronts with 255 are a bit stretched and it freaks me out just a bit. I'd definitely go up to 255. 265 is the perfect fit upfront but P-Zeros don't come like this. My rears with the 325 are a perfect fit, wondering if your 325 on an 11.5 barrel aren't to meaty?

[2007 to 2016 M6 Cab]

Originally Posted by Twitch Massacre

I must say I agree with M6-Coupe, not to mention the 245 on the 9.5 must be super stretched. I have a 21x9.5 fronts and 21x12 rears. My fronts with 255 are a bit stretched and it freaks me out just a bit. I'd definitely go up to 255. 265 is the perfect fit upfront but P-Zeros don't come like this. My rears with the 325 are a perfect fit, wondering if your 325 on an 11.5 barrel aren't to meaty?

I do agree with you, 255 or 265 would be ideal! However we were not able to find the 255 or 265 and 325 tire sizes in the 21s anywhere ... had a line on the front Michelin SS in 255 but no rears in the 325 were avail and we were looking since Dec 24 2014 when we placed the car order and started the rim design!

When we got a line on the 245 and 325 Runflats from Pirelli that had BMW's blessing, we jumped on them one week before the car arrived so we had rubber to mount on the 21s that had arrived the week earlier.

The rears on 11.5 barrels at first looked a bit meaty as my 2007 M6 on 20s ran 305/25Zr20s and 255/30Zr20s ... so that set upo looked great ... the new set up did bug me a bit, but after seeing no rubbing I was happy with them ... my last S63 AMG (2011) with 295/25Zr22 on the rear had a rub if I had anything in the trunk or at higher speeds over a bump, my 2015 S63 AMG with 22's and the same rear tires have no rub ... the rubbing was a pain in the ass ... so with this set up on the 2016 M6 with no rub I am happy with it ... comes down to function as well, and the slightly wider diameter also helps with clearing obstacles and fills the wheel wells better ... something my 2007 looked odd with as I never dropped it due to clearance issues for curbs and parking garages.

I do not intend to track this car as it will be my daily driver (27 km one way trip) to and from work on sunny days (20 km of this is highway through a National park at 90km/h or windy roads) ... with the top down and two booster seats in the rear!

Have a look at the 245's on my fronts!

The rim is just flush with the tire's widest point near the bead ...

It was a slight compromise, I do admit - however being runflats and actually fitting the car without rubbing was key ... and I do not bottom out in parking garages or going over a curb or driveways.

M6-Coupe, I sent Manu Gill at Aristo a text re the ET of the rears and will post when I hear back.

[brad850csi]

Is there much room on the inside as far as clearing suspension components or other things is concerned? Michelin make a 335/30/20 you see

[M6-Coupe]

Originally Posted by brad850csi

Is there much room on the inside as far as clearing suspension components or other things is concerned? Michelin make a 335/30/20 you see

That's the reason I asked about ET to know how far he has gone.
Twitch Massacre Do you know your rear rims' ET?
I believe you have not reported any inside rubbing issue right?

[BimmerGuy25]

Originally Posted by 2007 to 2016 M6 Cab

I do agree with you, 255 or 265 would be ideal! However we were not able to find the 255 or 265 and 325 tire sizes in the 21s anywhere ... had a line on the front Michelin SS in 255 but no rears in the 325 were avail and we were looking since Dec 24 2014 when we placed the car order and started the rim design!

When we got a line on the 245 and 325 Runflats from Pirelli that had BMW's blessing, we jumped on them one week before the car arrived so we had rubber to mount on the 21s that had arrived the week earlier.

The rears on 11.5 barrels at first looked a bit meaty as my 2007 M6 on 20s ran 305/25Zr20s and 255/30Zr20s ... so that set upo looked great ... the new set up did bug me a bit, but after seeing no rubbing I was happy with them ... my last S63 AMG (2011) with 295/25Zr22 on the rear had a rub if I had anything in the trunk or at higher speeds over a bump, my 2015 S63 AMG with 22's and the same rear tires have no rub ... the rubbing was a pain in the ass ... so with this set up on the 2016 M6 with no rub I am happy with it ... comes down to function as well, and the slightly wider diameter also helps with clearing obstacles and fills the wheel wells better ... something my 2007 looked odd with as I never dropped it due to clearance issues for curbs and parking garages.

I do not intend to track this car as it will be my daily driver (27 km one way trip) to and from work on sunny days (20 km of this is highway through a National park at 90km/h or windy roads) ... with the top down and two booster seats in the rear!

Have a look at the 245's on my fronts!

The rim is just flush with the tire's widest point near the bead ...

It was a slight compromise, I do admit - however being runflats and actually fitting the car without rubbing was key ... and I do not bottom out in parking garages or going over a curb or driveways.

M6-Coupe, I sent Manu Gill at Aristo a text re the ET of the rears and will post when I hear back.

Just to double check, your running 325 30 21's in the rear correct? Cause I want to order that same exact size for my rear but was really trying to see if it will fit and not hit the fender liner. It seems like you even have room to lower it as well. Cause I have KW V3's I want to close that gap, not going to lower the rear much just 0.5 if possible. What you think?

[Twitch Massacre]

Originally Posted by M6-Coupe

That's the reason I asked about ET to know how far he has gone.
Twitch Massacre Do you know your rear rims' ET?
I believe you have not reported any inside rubbing issue right?

I don't know the ET but I know ADV1 has confirmed they're about as aggressive as you can go. I was about to sell my wheels to my friend for his M5 and they said that if he even tried to put them on the wheels would stick about two inches past his fender. I have no rubbing issues at all.