[nil98]

Winter tyres fitted a couple of weeks back. Fuel economy has dropped off a cliff from nearly 40mpg to barely 30. Is that normal?
N

[aguycalleddb]

Originally Posted by nil98

Winter tyres fitted a couple of weeks back. Fuel economy has dropped off a cliff from nearly 40mpg to barely 30. Is that normal?
N

Winter tyres are terrible for economy, but 100% safer than summers especially if we get some of the white stuff.

I've gone for all seasons as a compromise but I'm not sure how good they'll be if we get a few inches of snow.

[gavinwong]

Originally Posted by nil98

Winter tyres fitted a couple of weeks back. Fuel economy has dropped off a cliff from nearly 40mpg to barely 30. Is that normal?
N

I used to use winter tyres, but haven't bothered the last couple of years.
Mainly had to change them as I used to drive to Germany, and winter tyres are a legal requirement there. I noticed a drop in MPG of 10-15% dependent also on the temperature. Also check the tyre pressure, as they are different to all season / summer tyres.
The other thing I couldn't stand with winter tyres was the tyre noise increase into the cabin above 60kmh, especially as they were also RFT's.

[HighlandPete]

Originally Posted by nil98

Winter tyres fitted a couple of weeks back. Fuel economy has dropped off a cliff from nearly 40mpg to barely 30. Is that normal?
N

That seems extreme for a tyre change. What did you change from and to?

Pressures can have a small influence, but I'd not expect more than a couple of mpg difference for a summer to winter change.

[paulockenden]

They should make a small difference but 25% would suggest that something else is wrong. Are they ‘handed’ and if so are you sure they are rotating the correct way?

[Geoff G20]

That does seem a bit excessive but probably not a totally reliable test as a sample of 1, and as you (even subconsciously) know that there has been a change and you are potentially looking for a difference.

In scientific testing you would need to be unaware that anything had changed and even unaware that you were involved in a test.

[nil98]

Originally Posted by Geoff G20

That does seem a bit excessive but probably not a totally reliable test as a sample of 1, and as you (even subconsciously) know that there has been a change and you are potentially looking for a difference.

In scientific testing you would need to be unaware that anything had changed and even unaware that you were involved in a test.

I do a pretty consistent 130 mile motorway run every week so not entirely unscientific really. When u set the computer up there was an eco pressure setting so I will look that up when I'm next home. Rotation is fine.

I bought the car almost exactly 13 months ago and immediately put the winter tyres on. I do remember a marked economy improvement during the year which I put down to engine loosening up etc. now I know different lol
N

[HighlandPete]

Originally Posted by Geoff G20

In scientific testing you would need to be unaware that anything had changed and even unaware that you were involved in a test.

We'd really have to test in the same conditions, eliminate the variables and specifically test one tyre set after the other.

I've just looked at my fuel spread sheet for the 535i, over the past few years. There is no significant mpg difference in running summer or winter tyres. Within a 0.5mpg variation, most years, winter to summer periods.

I'm on 18" Continental Sport Contact SSR summer tyres and 17" Dunlop Winter Sport RFT. So both RFT, and OE specs for my model.

My E91 suffered mpg drops in winter, but most of that was due to the lower temperatures and additional energy demands, not the tyres.

[Dave_3]

I am the same as Pete, I don't see any noticeable/appreciable change in mpg due to winter tyres.

Shorter trips are affected more by the low temperature for me.

I was out last night visiting some friends for dinner. I noticed after about 15 kms autobahn, and 15 minutes urban driving at around 2 degrees I was over 50mpg.

Last week during a sunny but crisp afternoon, again over 52mpg.

https://g20.bimmerpost.com/forums/sh....php?t=1882694

Running 19" Continental * winter tyres supplied by BMW.

In fact, compared to my goodyear eagle summer tyres, I really like the continentals. They are much more relaxed, and less sensitive to cambers. Very refined also. Maybe a slight hint of a thrum when you get near 80mph. But around town great. I can just finger tip the steering.

D.

[Charlie (Wessex)]

Originally Posted by aguycalleddb

I've gone for all seasons as a compromise but I'm not sure how good they'll be if we get a few inches of snow.

I've used All Seasons on my Amarok (General Grabber AT3) and my old Golf R (CrossClimate+) in the snow, and they worked perfectly well, though when in the Alps, I had chains in the boot just in case.

Originally Posted by Dave_3

In fact, compared to my goodyear eagle summer tyres, I really like the continentals. They are much more relaxed, and less sensitive to cambers.

Have to say that I wasn't the biggest fan of the Eagle F1s that I have just taken off. Found that the car could be quite skittish, and find the CrossClimate+ are much more, using your description, relaxed.

[Mugspence]

I've swapped my 19" rims for smaller 18" winter wheels and tyres which are no longer staggered so it might explain why I haven't noticed any difference in mpg. (And the improvement in ride is fantastic!)

[paulockenden]

Originally Posted by Mugspence

I've swapped my 19" rims for smaller 18" winter wheels and tyres which are no longer staggered so it might explain why I haven't noticed any difference in mpg. (And the improvement in ride is fantastic!)

What did you go for? I was told that with the blue brakes not all 18 inch rims will fit. It would be interesting to know as it appears we have similar cars.

[Rhino at Work]

Originally Posted by paulockenden

What did you go for? I was told that with the blue brakes not all 18 inch rims will fit. It would be interesting to know as it appears we have similar cars.

Probably the same sizes as yours (G21 330i) - I'm running winters on 18" 790M wheels which fit no problem (19" 791M standard wheels).

[malibuboats91]

I'm running 225/45R18 Blizzak WS90s on my M340i. It's barely broken in and I've been getting around 30 MPG. Coming from a tuned S3 I'm really happy with the gas mileage.

[Charlie (Wessex)]

Originally Posted by malibuboats91

I'm running 225/45R18 Blizzak WS90s on my M340i. It's barely broken in and I've been getting around 30 MPG. Coming from a tuned S3 I'm really happy with the gas mileage.

If that is 30 US mpg that is about 36 imperial.

[Mugspence]

Originally Posted by paulockenden

What did you go for? I was told that with the blue brakes not all 18 inch rims will fit. It would be interesting to know as it appears we have similar cars.

Mine are 796Ms for my 330e. No problem with fitting over blue calipers.

[HurlyDog]

Originally Posted by paulockenden

What did you go for? I was told that with the blue brakes not all 18 inch rims will fit. It would be interesting to know as it appears we have similar cars.

17" BMW 778 fit. I have them on my G21 330i.

[paulockenden]

Originally Posted by HurlyDog

17" BMW 778 fit. I have them on my G21 330i.

Really? With the blue brakes? Everywhere else I've read online says 18" minimum, and even some of those don't fit.

[HurlyDog]

Originally Posted by paulockenden

Really? With the blue brakes? Everywhere else I've read online says 18" minimum, and even some of those don't fit.

Yes, they fit with the blue brakes. My standard wheels are 19" staggered setup, the 778 are a square setup. I have Goodyear winter tyres 225/50 17
I have just taken a photo but am struggling to get it on here - what photo hosting service are people using nowadays?

[HurlyDog]

View post on imgur.com

The angle makes the gap between the rim and the caliper look tighter than it really is.
Will take better shots when it stops raining

[paulockenden]

That's really interesting. Pretty much everywhere else suggests that the 18" 796M is the smallest that will fit with those callipers, but your photo proves otherwise!

[HurlyDog]

I enquired with my local dealer and was given four options in 17 & 18 inch wheels. 790m and 796m in 18, 776 and 778 in 17 inch. I went for 17" due to the greater choice of winter rubber and the fact the 18" options were staggered, so with 17" I am able to swap front to back if needed. I bought the 778 as an ex display set from Chesterfield BMW.