[Oldguysrule]

Started a separate thread for this size. For anyone wanting to ditch the RFT, I believe this is a good solution. These tires sidewalls are 4/10 of an inch higher than the stock size (245/40/21 and 275/35/21). Speedo should register right on instead of 2-3 mph under. Rolling circ. difference for the X Drive is zero. The tires do not fall outside of the wheel width tolerences like some other fittments. Costco has a rebate on top of Michelin's right now so $150 off on 4. The Pilot 4 all season tires are available in this size. There may be others as well.

[OciWan]

Has anyone tried this setup?

[Kief]

Let our resident expert/tech freshxdough chime in...

[freshxdough]

Dunno. Someone be the Guinea pig. Should work.

[MyfirstBMW_X3M40i]

I may well be the guinea pig, but plenty of miles to go yet, but also plenty of time to think this or the 255/295 solution, it'll be one or the other. Im just conscious of how these would affect any warranty/mtce issues if it ever came up.

[Oldguysrule]

The only difference from stock is the profile which accounts for each tire being 4/5 of an inch taller than stock. That translates to a sidewall 4/10" higher. Width is the same as stock so no clearance issues. Width also does not exceed stock wheel max width. I'll be doing this size next tire change. I'm not crazy about 295s in the rear or the X3M option so for me, this is ideal until stock size becomes available. It might even be better cuz you have a tad more sidewall.

[Kief]

IDK, I think all the members here running 255/295 speaks volumes and I haven't read anyone suggesting problems.

[OciWan]

I've got 13.6k on my original Alenza RFT. So I need to make some decisions at some point.

Was debating between 3 options.

1 - Michelin Primacy AS. Pros stock size Cons not speed rated.

2 - Michelin PSAS with the 255/295 setup. Pros done my other forum members. Cons Rear rim size is technically out of fitment

3 - Michelin PSAS with this new size. Pros keeps the original profile of the tire more or less. Cons No one has done it.

Let me know what people think. Thanks.

[Oldguysrule]

Originally Posted by Kief

IDK, I think all the members here running 255/295 speaks volumes and I haven't read anyone suggesting problems.

Yes, but size exceeds stock rim tolerance and many space them because it is a close fit to shocks. 295 is a lot of meat in back. 275 would be better in snow. 255 in front also stretches recommended width for those rims as it does for X3M size. These are closest to stock as far as I can tell.

I also think this size is what BMW specs in their 20" wheels. 245/45/20 and 275/40/20.

[s5sportback]

Has anyone tried this set up yet?

Deciding on A/S tires for my 21 inchers is driving me nuts

[Banafu]

Originally Posted by s5sportback

Has anyone tried this set up yet?

Deciding on A/S tires for my 21 inchers is driving me nuts

I’m in the same exact boat right now . I’m looking for A/S tires . Trying to find them for 21” is hard. Someone quoted me $500 per tire ($2,000 for all 4)
I’m debating if I should spend that much or downsize to 20” or 19” if I find some nice rims and get the new tires (supposedly would work out cheaper than just to get the 21” tires and then finding tires for the smaller sizes would be a lot easier and less time consuming than the 21”

[Oldguysrule]

Originally Posted by s5sportback

Has anyone tried this set up yet?

Deciding on A/S tires for my 21 inchers is driving me nuts

I have not but plan to in spring when I ditch the RFTs. I did speak to two installers telling them what I have currently for wheels and tires and they both stated this size in 21s should create no problems and be almost identical in fitment to stock except for the sligh bump in sidewall height which also puts the speedo right on with actual speed vs 2-3 mph off. I'd suggest you do the same to ease your mind. All the other options in size present at least one if not 2 issues with tire width exceeding rim width specs (meaning slightly pinched sidewalls).

[OciWan]

I will probably try this setup out or use the stock setup on Michelin Primacy with the lower speed rating. 14.6k miles on my Bridgestones so far.

[Oldguysrule]

Originally Posted by OciWan

I will probably try this setup out or use the stock setup on Michelin Primacy with the lower speed rating. 14.6k miles on my Bridgestones so far.

This thread deals with 21" tires. Unless I'm wrong, Michelin only makes one 21" Primacy tire and its a 235/50/21. Wont work.

Pilot Sport 4AS and Crossclimate2 are avail in 245/45/21 and 275/40/21. So are Pirelli Scorpion Zero AS which are run on VW Atlas, Range Rover. Not rated for higher speed tho.

[OciWan]

Originally Posted by Oldguysrule

This thread deals with 21" tires. Unless I'm wrong, Michelin only makes one 21" Primacy tire and its a 235/50/21. Wont work.

Pilot Sport 4AS and Crossclimate2 are avail in 245/45/21 and 275/40/21. So are Pirelli Scorpion Zero AS which are run on VW Atlas, Range Rover. Not rated for higher speed tho.

I have 21 on my X4.

This is what I was looking at

[Oldguysrule]

Sorry, wasn't looking at 40 and 35 apsect ratio. Primacy might be an option in 21" then but it's not a highly rated tire based on Tire Rack and others. Ill be looking to do the Pilot Sport in 45/40 ratios.

[OciWan]

Originally Posted by Oldguysrule

Sorry, wasn't looking at 40 and 35 apsect ratio. Primacy might be an option in 21" then but it's not a highly rated tire based on Tire Rack and others. Ill be looking to do the Pilot Sport in 45/40 ratios.

No worries. And that's why I said I would use the stock setup with the Primacy.

But I do like your setup as well. Thanks for coming up with it.

[Poloblue]

Since all season's are quite hard to find in stock tire size (245/40/21; 275/35/21), does anyone have experience running summer tires all year in "warmer" climates (CA, FL, AZ etc)? Wondering how summer tires perform in winter months and in inclement wether if it can get as low as 40 degrees (but generally never below that)?

[509er]

Originally Posted by Poloblue

Since all season's are quite hard to find in stock tire size (245/40/21; 275/35/21), does anyone have experience running summer tires all year in "warmer" climates (CA, FL, AZ etc)? Wondering how summer tires perform in winter months and in inclement wether if it can get as low as 40 degrees (but generally never below that)?

At the risk of , I think based on your stated criteria that you'll be just fine running summer tires in those climates/conditions. If you're planning to make trips over the Grapevine, up to Big Bear, then that would not be a good thing to roll the dice on summers.

P.S. I ran summers on my vehicles the entire time I lived in the Bay Area with zero issues. Carried chains for when I infrequently ventured into higher elevations.

Cheers~

[glennbk]

Any experiences on areas that get colder, like Dallas?

[comber]

Originally Posted by Poloblue

Since all season's are quite hard to find in stock tire size (245/40/21; 275/35/21), does anyone have experience running summer tires all year in "warmer" climates (CA, FL, AZ etc)? Wondering how summer tires perform in winter months and in inclement wether if it can get as low as 40 degrees (but generally never below that)?

In my area in Spain it's easy to have up to -15ºC some times, normal weather in winter means below 0ºC every night and not more than 8-10ºC during day, sometimes less. Made 45k kms last year and a half, always running summer tires with no issues at all.

Weather is dry, so almost never we have snow, but some times we do and in those conditions xDrive makes a good job.

Summer is totally different, we can have several weeks above 35º-40ºC.

Before I was running Alenza's (they are rubbish), now I'm running Michelin PS4s in stock tire size (245/40/21; 275/35/21) and man...these tires are amazing in every condition. I have almost 25k kms on them and looks like they can last another 25k, treadwear is impressive too.

[glennbk]

Sounds like your Spanish weather mimics Texas. How long did the Alenza's last and do you have any comments about why they were rubbish?