Three weeks ago fitted a pair of RS3 onto front wheels on my fabia mk2. And now fuel consumption has increased by at least 10%. Is it the tyres , or something else, driving style has not changed, it is noticeable when using cruise control.

A few things.

The tyres are brand new and should have maximum tread, so they can be slightly different circumference from what they replaced.

The tyre pressures and sidewall stiffness can mean a slight different circumference.

The tyre were brand new so can take a few hundred miles lose the greeness.

 

But imprortantly, is the profile giving more tread on the road, better traction so friction so safer and better handing tyres.

Different compound from ECO tyres / Ditch Finders.  ie tyres that are less grippy on road surfaces, dry, wet, warm or cold.

 

Is the actual range of a tank full of fuel dropping or just the figures on the Maxidot?

 

Always worth measuring old and new tyres side by side.  Just because both say 205/40 R 17 does not mean they are the same size.

Pirelli Zero Nero can be bigger than Dunlop Sport Maxx and the Rain Sport 3 can be bigger than Dunlop Sport Maxx in the same size.

205 is the tyre width, not the tread on the road width.

 

http://kouki.co.uk/utilities/visual-tyre-size-calculator

 

On the rear here.

The Pirelli that Skoda fit when customers complained of Pulling to the left. The Dunlop is on the car.

Hard sidewall and compound tyres with less tread on the road next to Dunlop Sport Maxx.  Both are 205/40 R 17.

On the front is a 215/40 R 17 M&S marked tyre, and the 205/40 R 17 actually is bigger, bigger circumference.

 

Edited 23 September, 20187 yr by Offski

Thanks for your comments much appreciated, acknowledge your point about makers sizes, fitted tyres as "same size"  and previous were all season ones and just changed the fronts.

Mpg has dropped on maxidot and measured full tank to full tank against trip mileage. Filled at same pump to first full auto stop.

Had TriStar all season all round, still good on rear, changed  cuz fancied different, going to swap RS to rear and see if that changes mpg, so I'll be dragging the RS3s. Probably the cause is the RS3s as they do have really have good grip in the wet, they've gripped past what I could corner with the TriStar ecopower ones. Just posted to see if any other briskodians had similar experience with RS3s.

 

Hi, I've recently changed from Goodyear F1's to Yokohama Advan sports and have noticed a drop of @4mpg overall. The Yoko's do get very warm and grippy but obviously have more rolling resistance hence the drop in mpg.

Actually just done mpg tank to tank and mines down by 3mpg to 35mpg. Going to soon change rears to fronts as I did have all 4 as TriStar allseason now only 2 on the back.