Driving at 88.5 KMPH for maximum fuel efficiency.

callybags said:
It was indeed reduced to 55 mph. Think it was the mid to late seventies. There was fuel rationing as well. I recall there being a limit of 3 gallons per car at one stage, and queues back down the road from garages.
Click to expand...

Thanks for that! (The other good thing about owning a Honda 90 in those days was that I could skip the queue and fill my tank while the owner of the car parked at the pump was paying for their petrol!)
 
Steven Barrett said:
Ever drive on the M50? Lots of drivers in the middle and outside lane driving at that speed, oblivious to the cars behind them as well as the rules of the road. :mad:
Click to expand...

Agreed. I have also sometimes been undertaken when driving at 100 kph (the speed limit) in the fast lane! Maybe one of them was you!
 
Purple said:
If all or most of the cars in the lane behind you are changing lanes to pass you, while still staying within the speed limit, then you are driving dangerously.
Click to expand...
So all heavy vehicles or vehicles towing that must adhere to lower limits are driving dangerously?

If a driver can't change lanes safely when they come across a slower (but not slow) driver then they are the problem and not the slower driver.
 
PGF2016 said:
If a driver can't change lanes safely when they come across a slower (but not slow) driver then they are the problem and not the slower driver.
Click to expand...
I agree. If a car is driving 30Kmph slower than the other cars on the road then they are slow (not slower) and and causing other cars to change lanes. That's dangerous.
 
Purple said:
That's the thing though, there is no fast lane. You drive on the left unless you are overtaking slower moving traffic. When the left hand lane is clear you move back into it.
Click to expand...

On the M50, the two left hand lanes are often clogged due to drivers queing for an exit - capice?

So I'll drive my way and I'll allow you to drive yours. OK?
 
Last edited:
Shirazman said:
On the M50, the two left hand lanes are often clogged due to drivers queing for an exit - capice?

So I'll drive my way and I'll allow you to drive yours. OK?
Click to expand...
If they are clogged they are moving more slowly than you so you’re overtaking them. No problem.
If they are driving faster than you then you are in the wrong lane and are driving dangerously.
I don’t particularly care but them’s the rules of the road.
 
When I commuted on the the South Link and motorway, I always drove at 90-100 km which usually just meant pulling in behind a lorry. I am a poor student and going 120kmph was 5.3 litres per 100 km while going 100kmph was 4.5 litres. An extra 10 minutes in commute everyday saved me a tank of diesel a month. Never had any issue with being perceived as a reckless driver, or had any issue as people could overtake me doing 110 km.

In regards to everyone else on the road. The speed limit is the limit not the target. No court is going to convict someone for negligent driving when their rear ended while going at 75% the maximum speed. If the government felt that safety demanded a minimum speed it would be prescribed. God knows the RSA are quick to lobby for everything else....
 
T McGibney said:
The ironic thing here is that if your speedometer is telling you that you're travelling at 88kph, you're probably actually moving at 4-5kph slower than that.
Click to expand...
By law, car manufacturers are actually obliged to ensure that the speedometer displays at least 5% in excess of the actual speed. So real speed of say 83kph will indeed be recorded as about 88+kph. You can see this very clearly if you use Google Maps as your (handsfree of course) GPS, with Google giving you an accurate speed reading.

BTW, I've often wondered if this enforced error feeds through into odometer readings as well?
 
Last December the week before Christmas while driving from Wexford on the M11 a driver came towards me on my side of the motorway on the outside lane. He caused two accidents. This is apparently quite common. Always drive on the inside lanes.
 
VonHohenzollern said:
In regards to everyone else on the road. The speed limit is the limit not the target. No court is going to convict someone for negligent driving when their rear ended while going at 75% the maximum speed. If the government felt that safety demanded a minimum speed it would be prescribed. God knows the RSA are quick to lobby for everything else....
Click to expand...
I didn't know this until about five years ago that there is actually a recommended and a mandatory minimum speed on roads in Europe so I presume it's the same here
These are the blue round and square speed signs and as far as I can remember round is mandatory and square is the recommended
 
Optimal+Speed+For+Minimum+Fuel+Consumption.jpg
 
Shirazman said:
On the M50, the two left hand lanes are often clogged due to drivers queing for an exit - capice?

So I'll drive my way and I'll allow you to drive yours. OK?
Click to expand...
The outside lane is the overtaking lane. It is not for people to cruise along. Likewise, it is not up to a driver going 100km to decide that other drivers should go that speed too in the overtaking lane. On busy motorways like the M50, there will be a lot more cars in the outside lane, but you need to always ensure that you are not holding up traffic behind you.

If you drove on the speed limit in the overtaking lane on the continent, you'd be run off the road, especially on the autoban in Germany.


www.theaa.ie

Motorway Rules in Ireland

Motorway driving is a mystery to many new drivers and even sometimes experienced ones. AA Road watch’s Chris Jones shares the motorway rules in Ireland.
www.theaa.ie www.theaa.ie
 
You must log in or register to reply here.
Back
Top