53mpg before tyre change,48mpg afterwards

[FROGGY]

Speechless............

[bassman]

Originally Posted by ice man

To be honest, going up and down a few MPG is normal, even if you are driving very consistantly.

All it takes is for the wind to pick up, slightly lower pressure in the tyres, a bit of brake bind...

if you are driving to achieve economy like that, ie very gently and not too fast, the smallest things could have a noticeable impact.

I'd say check tyre pressure and tracking. If OK then still dont panic!

48 mpg is still very good for this size of car

ATB

Trev.

Yes it is......but not good when it suddenly drops from 52/54 to 47/48, and the only obvious thing is the tyre change....I check my mileage all the time, run with my OBD on the mpg window, so Ive learnt the moves that have a noticeable impact on the mpg.........and Ive done none of them.....except change the tyres....which Ive done a few times previously and not lost mpg.

[VMax1000]

Originally Posted by bassman

Yes it is......but not good when it suddenly drops from 52/54 to 47/48, and the only obvious thing is the tyre change....I check my mileage all the time, run with my OBD on the mpg window, so Ive learnt the moves that have a noticeable impact on the mpg.........and Ive done none of them.....except change the tyres....which Ive done a few times previously and not lost mpg.

Remoulds may not be accurate on diameter from set to set. May affect the the accuracy of the mpg reading.
Rolling resistance, as mentioned before, may impact as well (rolling resistance = compare pushing a smooth piece of paper over a piece of wood vs. sand-paper over wood). More power needed = more fuel.

If I may ask, what's the obsession with mpg ?

47mpg is roughly 13p a mile, 52 about 11.8p a mile @1.36 a liter

With 10k a year thats about £8 - 10 a month difference

[bassman]

Originally Posted by VMax1000

If I may ask, what's the obsession with mpg ?

47mpg is roughly 13p a mile, 52 about 11.8p a mile @1.36 a liter

With 10k a year thats about £8 - 10 a month difference

Been driving 45 years, and just discovered that its more enjoyable, less stressful. not having to rush around in the car, at the same time watching my mpg rise....Why waste £10 a month, when its more enjoyable to drive sensibly......Long gone are my Escort Mexico(with 2 twin Webers) days.