Not sure if this is relevent but did you change tyres before the really cold winter has set in?

My economy has gone down since all the really cold winter days have set in and economy has dropped around 3-4 mpg and that's without changing tyres

Not sure if this is relevent but did you change tyres before the really cold winter has set in?

My economy has gone down since all the really cold winter days have set in and economy has dropped around 3-4 mpg and that's without changing tyres

I just read through this thread from the start and this is also the first thing I thought of. Did the tyre change coincide with the recent drop in temperatures? Diesel economy usually drops in lower temps and it may just be this that you are seeing.

Well, some great comments in this thead, cheers and to all the posters.

I'm quite aware of the difference the temperature can make to fuel efficiency, the most part being because the engine takes that much longer to warm up, combined with more use of all the electrical systems (heated seats;) ) etc. But on a long run, with the ambient temperature around 6 degrees, I would expect IMPROVED economy over a significant distance, not worse.

I think a 5-10% reduction in economy is reasonable, and should have been expected really. I guess that the tyres offer a good 30+% increase in grip over the Bridgestones. I paid nowt for the tyres, so really, what am I complaining about!

Long runs will be affected too as the density of diesel changes with temperature.

Thats why diesel engines have a sensor for this and is what the EVRY mod exploits for more power. It fools the ECU into thinking the diesel is at a lower temp so increases fueling to compensate.

I always find the first couple of thousand miles on new tyres an mpg killer, after that it eases off a little, brand seems not to matter too much on easy non agressive drives with regards to fuel consumption

I thought that there was a diesel return line, that in effect heats the diesel up?

Ah well, either way, I've decided to just ignore the MPG readout display from now on, enjoy the car, and stop being a stingy git.

fuel economy depends on several factors. if you're concentrating on tyres, have you looked at tyre pressures?

don't forget that fuel economy is affected by a whole manner of things.

I have a fabia 1.9tdi.. so not too disimilar from a bog standard vRS, however, I swear by my Dunlops. Good grip in all conditions and I got 70,000 miles out of my rear tyres, 35,000 each on my two sets of fronts.. (fronts take a lot more hammering of course).

I've had 72.2mpg out of my fabia (best recorded to date) and generally get in the 60s mpg when doing Oldham to Oxford commute (and back). I generally run with 34psi in my tyres all round.. people often set some lower than others.. but with weight in the boot and an heavy engine in the front.. I think even stevens is the best approach.

Regards,

dont forget new tyres take a few thousand miles to "wear" to the suspension geometry of the car... bearing this in mind, brand new tyres are acting against the suspension and forward motion..

tyres are no excuse for driving through fields

back to the topic at hand' date=' rim protection you say? :rubchin:[/quote']

PMSL

Also factor in winter diesel which may give less power than the summer stuff by virtue of a lower calorific value.

Chris

Zero Neros do lead to a drop of up to 5mpg. Have a look at my tyre reviews in the review section on here for others I've tried.

Glad to hear you like the Neros though, I rate them most highly of all the pure road tyres I've tried