BMW F10 - New tyres & Warning lights

Iceweasel

So this a square set up on a BMW 5 series - not an M-Sport?

There are several reasons you are getting warming lights due to the car receiving illogical signals from various sensors.

Apart from that run-flats and conventional tyres should not be mixed - you need to have all RFs or all non-RFs - all tyre manufacturers and your car's handbook agree on that.

The handling is now compromised and in the event of an accident you have given your insurance company a huge amount of 'wriggle room' to refuse a pay-out.

Next the tyre size - they ought to be 225/55 17 - any other 17" size on the front axle is just plain wrong.

225/45 17 is a size for e36 & e46 3 series or e39 5 series.

F10 M-Sports with staggered 18" 19" or 20" wheels have lower profile tyres and if you want lower you will need to change the wheels to some of those.

The 225/45 tyres are approximately 7% smaller - which apart from being too small in diameter for the F10 the difference is way beyond what could be deemed an acceptable alternative.

To get the right diameter on 45 profiles you would need to fit 275/45 17 tyres which apart from being an 'unusual size and possibly don't even exist, would be far too wide for your 8" wide rims.

As it is your speedo will be inaccurate, fuel consumption will be increased, warranty (if you have it) will be null and void, and even if you change to 225/45 17 runflats your insurance company may deem that 'wrong' size to be a modification.

Best stick to the correct size or buy new wheels.

AdrianC

cw212010 wrote: »

I don't have an issue doing this, however the 45's are much nicer with the low profile look. The 55's belong on a truck there's more rubber than there is alloy!

<gibber>
No... Just... No.

If you want to fit lower profile rubber, fit larger-diameter rims, too, so the rolling radius stays the same (or similar), and the speedo and odometer don't under-read. With the smaller tyres, for every 10,000 miles you actually cover, the odometer will be reading 10,700.

Are the smaller tyres suitably load rated for a big, heavy car like a 5? A quick look says that 91 is typical non-XL rating for 225/45 17, and 97 for /55.

Oh, and don't forget to tell your insurer.

(Anybody else thinking DM?)

photome

AdrianC wrote: »

<gibber>


(Anybody else thinking DM?)

Surely not enough posts, been a member since dec and only 16 posts BUT striking similarity

force_ten

what you have done is just wrong

get the 245,s off and fit the correct size tyres

The guy selling the tyres told you they would be alright because he wanted the sale so wasn't going to tell you they were just wrong

harveybobbles

Guess its these wheels? If so, them 17inch wheels do look quite small compared to the car.

cw212010

Thanks for the responses everyone, Iceweasel you cleared up a lot.

Will call them and ask to have them changed.

Thanks!