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[Pron1series]

Hi guys,
I'll finally be picking my car up from the dealership after its arrival from Bremerhaven. I'm planning on replacing the runflats that come with the 128i M-Sport package with a non-RFT. The stock tires are 205 wide (205/50/17) in the front and 225 (225/45/17) wide in the back. My only question is should I stick with this width or go wider? If I do go wider, do I stay with the 50 and 45 measurements as well?

Help is appreciated, thanks!

[gregthegr8]

You should ask Simian who is getting the michelin pilot super sports probably put on as we speak. He went with a square setup, which I imagine you may not want to. I'd also be curious to hear where you are going to use to swap the tires as I plan on doing mine soon and been doing research to get the best prices and a place I trust since my dealer wouldn't touch the issue.

[Pron1series]

Thanks for the help Greg. I'm finding the best prices to be online (the usual sites of tire rack and tire buyer). I suspect if I brought the online prices to a shop, the shop could match it or beat it with overall costs including installation but to be honest I really don't know. Going to continue to do more research but still want to know if I can go a little wider on the stock wheels! I'm not really interested in doing a square set up though.

[gregthegr8]

Best online prices I found were at discounted wheel warehouse in OC, but they have some really bad yelp reviews, so I pretty much just intend to use them to get another place to price match. Might be different because I'm looking at 18's so you may find better sites/places, but America's Tire out in North Hollywood came highly recommended to me and they will price match any site + their shipping cost. Bit of a drive for me, but hopefully worth it.

Discounted wheel warehouse's prices for a set in 18s were almost $150 cheaper total than tirerack, plus the shipping costs would be cheaper. I think with tirerack though you don't have to pay sales tax, so have to figure that in.

Here's the link to their website if you want to comparison shop your size. Hope that helps. Anything to help out what will be like a lil brother/sister to my car and look very much the same. Cousins perhaps? I got a whole album online too of a mineral grey 135is with coral red interior to help you pass the time.

http://www.discountedwheelwarehouse.com/

[VMRWheels]

If you're running the stock wheels, I'd stick with the stock tire sizing.

[Pron1series]

where's the mineral grey album Greg? My car is set to arrive at the Port tomorrow - only a few more days!

[Pron1series]

If I increased the width up front to 215 but left 225 in back, would that cause a problem?

[Pron1series]

Any help is appreciated. Just looking for range of tire widths I can use on stock m sport wheels. Front is 17x8 and rear is 17x8.5. I imagine 205-225 is fine for the front and 225-245 is fine for the back but confirmation would be great. Thanks!

[Iron Man]

Originally Posted by Pron1series

If I increased the width up front to 215 but left 225 in back, would that cause a problem?

There are members on this board who went a square 225/45 with the 17X7 and 17X7.5 wheels

[Iron Man]

Originally Posted by Pron1series

Any help is appreciated. Just looking for range of tire widths I can use on stock m sport wheels. Front is 17x8 and rear is 17x8.5. I imagine 205-225 is fine for the front and 225-245 is fine for the back but confirmation would be great. Thanks!

Front M-Sport wheels are 17X7 and rear are 17X7.5. If you change tires, I would try to stay within 3% of the original wheel diameter, otherwise your speedo will be way off. I also would recommend the 1010tires website for wheel diameter calculations and looking at tire changes.

[bmw1racer]

Originally Posted by Iron Man

There are members on this board who went a square 225/45 with the 17X7 and 17X7.5 wheels

That's what I plan to do once I wear out these runflats.

[Black128i]

Congrats on your new 1er!

I assume your wheels are the same width and offsets as my 2009 128i sport package; 7.0/7.5 F/R width and 47 offsets.

I had no problem with 225/45-17 on the front stock wheels, and highly recommend it over the 205's, even if you stay with 225 rear. A 7.0" wheel can handle a 225/45 no problem. Diameter of 25" is the same 205/50 so no issue there.

I would recommend 235/45 or 245/45 rear if you want wider tires, since both of these can accept a 7.5" wheel. Check out the specs on TireRack for Michelin Pilot SS to see the tire dimensions and wheel requirements.

I haven't tried 235 or 245 rear since I had my rear wheels widened by 1.5" and run 255/40-17 Michelin Pilot A/S in the winter. However I have Apex Arc-8 summer wheels with 275/35-18 rear which is a taller tire, similar to the 245/45-17, and I like the additional 0.7" tire diameter since it fills up the wheel gap. It's only 0.35" taller, but it's noticeable and I like it.

Good luck and please post pics with your new tires.

[jb2178]

I did star specs 225/45 fronts and 235/45 rears and LOVE it!

[JimD]

I have Michelin Pilot SS in 225x45/17 on my 7 inch front wheels and on my 7.5 inch rear wheels. They feel much better than my old run flats (smoother, stickier, noticably stickier in the wet, quiet, overall great). My independant installer had no issue with installation on the front wheels and I think they look fine.

Jim

[Kontra]

I've done some mild searching, do not want to hijack this but will I be okay running 225/45 on my stock rims, non sport package. Stock is 205/50 square. My tires are going to be slicks if I keep driving them another week so I have to get on this.

[Iron Man]

Originally Posted by Kontra

I've done some mild searching, do not want to hijack this but will I be okay running 225/45 on my stock rims, non sport package. Stock is 205/50 square. My tires are going to be slicks if I keep driving them another week so I have to get on this.

Your wheels are 17X7, and people have already mentioned here that they put 225/45 tires on 17X7 rims.

[Kontra]

Thanks, just wanted to clarify.

[Pron1series]

So the purposes of going with a square set up is both to reduce understeer and have the ability to rotate. My last question relates to rotating the tires - with same size tires you can rotate, but will the fact that the front wheels are narrower than the rear wheels matter for rotating? Thanks again for all the help.

[jb2178]

Originally Posted by Pron1series

So the purposes of going with a square set up is both to reduce understeer and have the ability to rotate. My last question relates to rotating the tires - with same size tires you can rotate, but will the fact that the front wheels are narrower than the rear wheels matter for rotating? Thanks again for all the help.

I do/would not rotate my staggered 17 inch wheels, even if I was running the same width tire the width of the wheel also affects how wide the tire actually is. You will have more rubber on the road on your 7.5 inch wide wheels than your 7 inch wheels.