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Discussion Starter · #1 · (Edited)
As the outside temperature begins to drop (it’s 8 degrees here in Scotland today) I’ve noticed a step change in the range (actual not GOM). I usually get over 4 m/kw in the warmer weather (approx 160 mile range) but yesterday in the rain and low ambient temperature and wet conditions I noticed it dropped to less than 3 m/kw (approx 120 mile range) - in part this is as I also had the heater on 🥶. I know this is to be expected as cold temp = reduced range.

However one thing I have noticed is that in the warm weather the tyre pressure at driving temperature is 2.4 bar however in the cold weather it’s 2.2 bar. I expect this will contribute to the range degradation so plan to increase winter pressure to at least 2.4 bar.

Would be interested to know if anyone else has seen this and if the range degradation is reduced by better winter tyre pressure management.
 

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About 30 years ago I noticed my ICE car tyres needed topping up almost every month in autumn, and not at all in spring. Presumably as temps got colder, the pressure got less, and increased as they warmed up. I think it's good practice to check all your tyres weekly as it grows colder.
 

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Kia e-Niro 4 MY20, Zoe Z.E.50 GT Line
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The Zoe complained about tyre pressures this morning, first day it’s been a bit cold. i have to admit to lacking discipline about tyre pressures.
 

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Zoe Devotee
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I've seen a good 4psi drop from a warm day (over 14 degrees) to a cool day 8 degrees. I'd top them up before I go on a long trip, but at the moment there is the odd warmer day where pressure shoots back up.

Today I saw 2.4mpkWh on a wet motorway trip and it was windy. :ROFLMAO: I was doing 70mph and enjoying passing all those toddling along in their diesels trying to max their mpg. It did go up to 3.1mpkWh when I got back onto rural roads.

Looking forward to a cold trip to Filey in a couple of weeks. Be interesting to see how I manage, only plan to stop once.
 

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Tyre pressure has next to no effect on efficiency. Just make sure they're at least at manufacturer spec when cold (pressure goes up 4-5psi once the tyres warm up so never try to set the pressures on warm tyres!)

The speed you drive at does have a huge effect, as does the weather (which you can do bugger all about).

Seeing 2.4 @ 70mph is very normal for cold days.
 

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Zoe Devotee
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Tyre pressure has next to no effect on efficiency. Just make sure they're at least at manufacturer spec when cold (pressure goes up 4-5psi once the tyres warm up so never try to set the pressures on warm tyres!)

The speed you drive at does have a huge effect, as does the weather (which you can do bugger all about).

Seeing 2.4 @ 70mph is very normal for cold days.
It sure is with pressure showing under 40psi when warm. ;) 4 degrees warmer and the tyres are back just over 40psi after a run and the range is much higher.
 

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Tyre pressures have a small effect on efficiency unless the tyre is very underinflated. Wet roads especially standing surface water which has to be expelled to the sides of the tyres by the tread pattern dramatically increases rolling resistance.

My Leaf dropped from 3.8 miles/kWh average this time of year on my daily commute to a pitiful 2.9 miles/kWh for one day last week - the temperature was about the same, the only difference was heavy rain and a lot of standing water on the road especially at the sides of the road.

The next day was just light drizzle and the miles/kWh was back up to normal again. So my money is on wet roads being the main factor.
 
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