[njc]

Now that I have my G31 520d my winter set up from my F11 doesn't fit due to a change in PCD from 120 to 112. The research I've done so far is that the 7 series (G11/12) has the same size wheel inc PCD, Offset & CB as the G30/31 apart from tyre size - specifically 18" Winters. G30/31 is 245/45/18 and G11/12 is 245/50/18.
The wheel and tyre packages seem to come in cheaper for the G11/12 so can I fit slightly larger tyre on my G31 without any major issues?

[morellomax]

Or you could buy a set of "as new" G11/12 wheels off ebay and swap the tyres over, then sell the unwanted tyres and rims, either separately or as a complete set for the previous 7 series and 5 GT, which have PCD 120 and the 245/50 18 tyre size.

[njc]

To be honest my current winter tyres are not worth selling - they are just above legal. The alloys are fine bar a couple of marks. Hence me looking for a new set complete - I might even look at 17" if it is a cheaper option.

[JLR1969]

I do think that the whole winter tyres thing is a bit of a marketing con.

I don't doubt that they improve performance in certain conditions but in reality in the UK they are a waste of time and money.

I have been driving in the UK for 30 years and never had a problem.

If there is snow on the roads I stop in and make other arrangements, you may have snow tyres but the other 99% of drivers don't.

As I say I appreciate they offer improved grip but driving with the road conditions in mind ie slowing down seems to have been good enough in the past.

[njc]

Originally Posted by JLR1969

I do think that the whole winter tyres thing is a bit of a marketing con.

I don't doubt that they improve performance in certain conditions but in reality in the UK they are a waste of time and money.

I have been driving in the UK for 30 years and never had a problem.

If there is snow on the roads I stop in and make other arrangements, you may have snow tyres but the other 99% of drivers don't.

As I say I appreciate they offer improved grip but driving with the road conditions in mind ie slowing down seems to have been good enough in the past.

Hear what you're saying - my requirement for winter tyres is due to driving to the Alps at least twice during the ski season. It is law in Germany to have them fitted even if transiting through and to be honest I wouldn't even attempt the journey without. France experiences so many problems with UK vehicles getting stuck and causing major hold up due to cars not being fitted with winter tyres or even snow chains.

[Cilonen]

Originally Posted by njc

Now that I have my G31 520d my winter set up from my F11 doesn't fit due to a change in PCD from 120 to 112. The research I've done so far is that the 7 series (G11/12) has the same size wheel inc PCD, Offset & CB as the G30/31 apart from tyre size - specifically 18" Winters. G30/31 is 245/45/18 and G11/12 is 245/50/18.
The wheel and tyre packages seem to come in cheaper for the G11/12 so can I fit slightly larger tyre on my G31 without any major issues?

You can make this change, but it will mean the wheel & tyre have a rolling circumference larger than the standard set - 73.89mm or 3.62% to be precise.

This won't realistically affect handling, but will mean your speedo will be out - speedo reading 70mph means you will be doing 72.5mph (assuming speedo is accurate, most are geared to overestimate speed anyway)

Your odometer will also be out by the same degree, but opposite: 1.00 miles recorded for every 1.03 miles traveled - after 10,000 miles that's just 9638 miles recorded on the odo.

[Im1]

Suggest all season Michelin cross climate tyres . Unbelievable performance in both summer and winter conditions . The ambulance service use them to avoid constantly changing wheels .

[njc]

Originally Posted by Im1

Suggest all season Michelin cross climate tyres . Unbelievable performance in both summer and winter conditions . The ambulance service use them to avoid constantly changing wheels .

I am seriously considering them - just wish they did them in really runflat.

[Im1]

Originally Posted by njc

I am seriously considering them - just wish they did them in really runflat.

Yes I too thought the same but now am so glad I changed to non run flat as the ride has been transformed on my F10. Also 3-4 mpg better economy than pirelli cinturanto run flats

[njc]

Originally Posted by Im1

Yes I too thought the same but now am so glad I changed to non run flat as the ride has been transformed on my F10. Also 3-4 mpg better economy than pirelli cinturanto run flats

What is the wear like - comparable to a normal tyre or does it wear quicker?

[Im1]

Originally Posted by njc

What is the wear like - comparable to a normal tyre or does it wear quicker?

Can't comment on this yet as only fitted in August. I am so pleased with wet / dry / cold performance that I would be happy for 10000 miles ( the cinturanto runflat lasted 22000 on the rear) .

As well as the hassle of changing wheels every season I am pleased to be avoiding any possible thread damage to hub sockets with repeated wheel changes .