ALT-4 What Reduces Fuel Economy
In the forty years which have passed since I got my driver's licence, I have owned seventeen cars, ten motorcycles and one scooter. Having worked mainly in small, undercapitalised businesses or larger parsimonious ones, I have been keenly aware of running costs, particularly fuel, and I have learnt a lot about the things that affect it.
The first and most obvious factor is the vehicle itself. In 1979 I bought a 1953 Humber Super Snipe, a large, handsome and deceptively fast and agile car. I discovered that being a purist and insisting on fitting cross(bias)-ply tyres was extravagant because the front pair lasted barely 4000 miles. Radials lasted much longer and transformed the handling. Alas, it was not possible to transform the car's fuel consumption so easily, or at all. I was told, most earnestly, that I could get twenty miles per gallon if I never went over forty miles per hour, to which I replied that if I were that keen to save fuel I wouldn't have bought a big heavy accelerative car in the first place. Big cars with enough power consume a lot of fuel. So do big underpowered cars because the inadequate engine is likely to suffer from chronic overwork. So my Humber was thirsty, as was a Vauxhall Velox (which failed to live up to its boastful name) which suffered from mechanical senility and a first-generation automatic transmission. In contrast my 1974 Audi 100GL was fast and economical (28-31 mpg) because it was light and had a very efficient engine with very well-chosen gear ratios. So was my Renault 17TS until rust ate it.
After the choice of vehicle, the two most important reducers of fuel economy are bad maintenance and bad driving.
Underinflated tyres waste fuel through increased rolling resistance, and they soften steering response as well. Modern engine management systems tend to be neglected, and when injectors and butterfly valves and linkages get dirty, more fuel is wasted. If black smoke follows you around, you're not only wasting fuel; you're also shortening your engine's life.
Misaligned front wheels increase fuel consumption and wear out tyres prematurely. They also spoil steering and handling response.
Tailgating is an effective fuel waster. Driving too close to the vehicle in front of you ties you to that driver's style, and if it's me you're bullying in this way you'll find yourself leaving all your braking to the last moment, and you'll be taking curves at the safe limit of my car's roadholding (which may be beyond your limits). In any case, removing your reaction space by tailgating eliminates any real chance of driving smoothly and efficiently.
Stamping on the accelerator, stamping on the brake, failing to change gear in time so that your engine has to work outside its comfortable speed range, all reduce economy. Using your car to store heavy things is another waster.
You may have noticed me hinting in places that economical driving habits are also safe ones.
Being in a hurry in peak traffic is wasteful. You've surely seen impatient fools weaving through heavy traffic, pushing into another lane, weaving around other cars, all to get to the same destination as you but thirty seconds earlier....I hope they've got something interesting to do with those seconds saved at such cost.
Finally, if you're drawn to motorcycles but you want to increase your fuel consumption, be encouraged. Many performance bikes in the 900cc - 1400cc range, and some cruisers as well, can return as little as 30mpg when ridden briskly. I suppose that's why the world in which I ride is dominated by more softly tuned 650cc bikes.
So, if you want to increase your fuel consumption on four wheels, buy something heavy with a generous frontal area, a high drag coefficient, and the largest available engine. Fit it with the widest tyres you can get, and drive it as aggressively as you can. Organise yourself so that you always forget a few grocery items, and try to leave a bit late for important appointments.
On two wheels, buy something that suggests road-racer or supermoto, and ride it as if tyres and brake pads are issued free of charge.
