[vicky57t]

Hello,

I've got a e90 (318i) 2007 reg which I bought recently.
It was only recently that I started looking at tyres as they will need changing soon. I had a look online to see what is recommended for my car and most of them come up with the following tyres/config:

225/45 R17 091 W both the FRONT and REAR

225/45 R17 091 W FRONT tyre 255/40 R17 094 Y REAR tyre

225/40 R18 088 W FRONT tyre 255/35 R18 090 W REAR tyre

I had a look at it turns out that all the current tyres on my car are:

205/55 R16 91V (not sure if runflats it doesnt have the symbol, they are Kumho Solus tubeless radials) which seems different to the config I am getting online

So I had a couple of questions I hope you guys could help out with (if it helps I drive no more than 5000 miles annually ):



1. Is the recommended tyre type really 225/45 R17 91W? (as shown online on Halfords etc) - I cant find the user manual and the door panel has a host of options listed :

2. What am I losing out by having the current size 205/55 R16 91V? Is it worth changing to 225/45 R17 91W?

3. If it is recommended that I go for 225/45 R17 91W, then is there any harm in changing the rears to these and keeping fronts as current 205/55 R16 91V (to save cost as front ones are in decent shape) ?

4. Should I go for Runflats or not (car doesnt have a spare wheel so I guess that answers this question to a big extent)?

Hope you can help as I dont want to get ripped off by dealers who have in the past always pushed for costliest option (even though with a different car).

Cheers!

[Chappers 71]

R refers to the wheel size, so R16 means you have 16" wheels on your car so ignore the R17 sizes
Run flats are the sensible choice as can drive at a reduced speed on them for a limited amount of miles
non run flats give a better ride & a lot of us that like to drive enthusiastically prefer them, but the downside is if you get a puncture although you can get an emergency tyre repair kit & carry that.

[vicky57t]

Thanks Chappers - that narrows down the list

if I go for the 16 inch options in the list from the door panel, what about 225/50 R16 92 for the rear ones - will I gain anything from the wider tyres/lower profile? or is it not recommended to have different rears and fronts?

[Chappers 71]

Yes you could go with wider rears which would give you a little more traction & grip. Downside is you would be unable to rotate your tyres front to rear, the benefit being able to rotate them is they will last longer.

Kumhos are a bit shit, there was a set fitted to my 540i when I bought it & they were terrible.

Goodyear or Michelin would be my choice but have a look on tyre reviews.co.uk it will help you make an informed decision

[vicky57t]

thanks a lot!

[bfleming]

Slightly late to this discussion, but here's my take.
That tyre sticker is specific to your car, so the tyre sizes on there are the ones that are permissible as far as BMW (& subsequently your general roadworthiness & insurance) is concerned.If you live elsewhere in the world, there will be an accompanying entry in your registration document that gives the wheel sizes that match those tyre sizes, but the DVLA doesn't support that in the UK. VOSA does though.
The sizes listed are pretty clear. The fact that you have 205/55-16's on your car currently is good - they're on your sticker. Run-flats aren't a legal requirement. Where you deviate slightly is that 205/55-16 91 H is specified, where 91 is the weight rating per tyre, and H is the speed rating. Your speed rating is V (which is higher than H) so you exceed the speed rating - no issues there, as you don't fall short of it.
You shouldn't mix 16 & 17 inch wheel diameters on a car - you'll end up with different style wheels & it'll look like a clown car.
In summary, the sticker is telling you to have:
205/55-16 91 H (min 91, min H) all round, or
225/45-17 91 V all round, or
225/45-17 91V front & 255/40-17 94 V rear (the staggered 17in M-Sport set up) or
225/40-18 88 W front & 255/35-18 90 W rear (staggered 18in M-Sport set up) or
225/35-19 88 Y front & 255/30-19 91 Y rear

As I have a 320d efficient dynamics the only permissible tyre size is the standard 205/55-16 91 V (& that's all that's written on my sticker).

Speed ratings & corresponding permissible MPH:
N 87 U 124
P 93 H 130
Q 99 V 149
R 106 Z 150+
S 112 W 168
T 118 Y 186

Weight Ratings:
Load Index & Load in kg
62 265 84 500 106 950
63 272 85 515 107 975
64 280 86 530 108 1000
65 290 87 545 109 1030
66 300 88 560 110 1060
67 307 89 580 111 1090
68 315 90 600 112 1120
69 325 91 615 113 1150
70 335 92 630 114 1180
71 345 93 650 115 1215
72 355 94 670 116 1250
73 365 95 690 117 1285
74 375 96 710 118 1320
75 387 97 730 119 1360
76 400 98 750 120 1400
77 412 99 775 121 1450
78 425 100 800 122 1500
79 437 101 825 123 1550
80 450 102 850 124 1600
81 462 103 875 125 1650
82 475 104 900 126 1700
83 487 105 925