I would like to increase tire size on 135i M package

Increase size front 215/40 r18 to 225 40 r18
Rear 245/35 r18 to 245 40 r 18

Will in increase in size fit fenders.

Car is still under warranty will this affect warranty?

I have that exact setup running Michelin Pilot Super Sports on my 2008 135i and I have had no problem with them fitting in the fender well.

The car has gone to the dealership for service several times since swapping out the run-flats for the larger standard tires. The only complaint they had was that I was no longer using run-flats and should come back next year and they'll put on the "proper" tires. It didn't affect my warranty though.

Thank you for that information. No more RFT

you can go 235/35/19 front and rear ... I had on mine .... No issue at all

Ok all, I have to ask: what are the biggest (widest) tires I can safely put on my 2008 135i M Sport with 18" wheels?

225/40/18 in the front, 255/35/18 in the rear, that's what I run on mine. If you want to go wider, you need to get wheels with a really high offset (Apex makes some) and depending on how wide, increase your camber and roll your fenders.

For anyone looking to replace their stock wheel/tire setup this is a great tool to play around with.
All you need to know is what your stock setup is, wheel diameter, width, offset and tire size.
Once you plug in those parameters you can make the changes that your considering and see the effect it will make on the fitment.
It helped me zero in on the perfect fit for me,

http://www.jonathanrowny.com/page/offset-calculator

GOod thread

ND40oz Just curious what tires are you running with the sizes you mentioned and after this period do you feel that the performance is still there with t he larger size as opposed to the stock 215/40/18 and the 245/35/18 ?

Thanks

I'm running Pilot Sport A/S Plus's, if you're looking for summer tires that outperform the stock rfts, you'll want to go with something like the Pilot Super Sports.

I have already researched and I am with you on the Michelin Super Sport and ready to order, just trying to decide on the 215/245 stock sizes or going up to the 225/255 you use.

I like the performance of the RFT 215/245 combo, just not the ride.

If you had it to do again would you go with the larger sizes ?

Thanks

Yes, well worth moving up in size, if not for the rim protection alone. One thing to remember is these are the sizes the 3er uses.

Thank you I think I will try that route
I am buying them at Americas tire and they will let me try them with 30 day return,

Probably have them in next week or so
Will give you feedback soon.

anyone know what the tallest tire size that will fit on 18" wheels is?

I have DW 245X35X19 - 275X30X19 on my 3 is anyone running these sizes in 18 on the 1?

I recently put 225/40/18 and 255/55/18 Non run flat, Pilot Supersports on my 2008 135M Converitble (auto tranny) and I do not think it would be wise to go bigger.

The clearances are just right and it fills the well very nicely.

These really work and there is no oversteer. The ride is sooooo much better. Plenty of performance, but I am not tracking this car.

Hope that helps.

Thanks so the input. I was thinking that a lower profile would help with the room. Car is still in transit & will be picking it up on April 4 so I will not get a chance to measure it before then. The factory stock tires are 225X40X18 - 255X35X18 on 313 wheels.

Thanks!

Originally Posted by bear-avhistory

Thanks so the input. I was thinking that a lower profile would help with the room. Car is still in transit & will be picking it up on April 4 so I will not get a chance to measure it before then. The factory stock tires are 225X40X18 - 255X35X18 on 313 wheels.

I didn't realize the 135is got 225 and 255s from the factory, BMW still lists it with 215s and 245s. If you want to go wider you'll need new wheels, with a high offset. Apex has a couple sets that fit the 1er and allow 275s in the back.

http://www.apexraceparts.com/1-series-BMW-E82_c_34.html

Just a note I think my speedo reads about 2 MPH higher than I am actually going based on what my Garmin GPS says.

My 2009 135 vert, w/ 18's and stock RFT's the speedometer is about 4-5 mph higher than my Garmin.

I am hoping when I switch to the 225/255 non-RFT's that my speedo will be more accurate. It sounds like yours is still a little off.

All BMW's read a bit high, its designed that way.

Originally Posted by ND40oz

I didn't realize the 135is got 225 and 255s from the factory, BMW still lists it with 215s and 245s. If you want to go wider you'll need new wheels, with a high offset. Apex has a couple sets that fit the 1er and allow 275s in the back.

http://www.apexraceparts.com/1-series-BMW-E82_c_34.html

Convert IS has bigger tires than the Coupe IS.

I guess the Higher reading speedo "by design" lets us all feel good about setting the cruise control at 80, but the cops see us going slower!!

I guess it's a lot better than if it was the other way around.

Originally Posted by bear-avhistory

Convert IS has bigger tires than the Coupe IS.

That's interesting, I wasn't aware of that. Can you tell me source of this info?

The 1 Series Coupe Standard and Optional Equipment brochure (Rev. August 13, 2012) shows 135is coupe with 215/40 F and 245/35 R. The 1 Series Convertible Standard and Optional Equipment brochure (Rev. August 13, 2012) also shows 215/40 F and 245/35 R. Would be interested to know if this has changed recently?

Thanks.