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A PHYSICIST WRITES . . .
(April 2013)
Since last month I’ve thought of more features that I shall want to look out for when I choose a new(ish) car soon. Forgive me for using these columns as my aide memoire, but I don’t want to have to write everything down elsewhere at this stage and risk losing the list!
Item: headroom. My Toyota Corolla gives me just half an inch of clearance in the driving seat – and a negative amount in the back, not that I ever need to sit there. But other people do sometimes, and I feel that if I apologize to them for the lack of vertical space, I am drawing attention to their height (and if I don’t apologize, maybe I’m pointing to their lack of it). There’s no reason, surely, why an otherwise well-equipped car can’t be made to accommodate a six-footer, front and back.
Item: a proper handbrake (ie, the lever with the button on the end). Some cars now have a lever or a button that applies the rear brakes electrically. Whether or not this is a good thing, it’s worrying that the systems differ between manufacturers. For example, the button or lever can be in various places. And you may have to push it to apply the brakes and pull to release, or else the other way round (I’ve read that you might even have to use the left foot to apply them, and then the right hand for release). The system may or may not operate automatically when you turn off the ignition. It may even be programmed so that the brakes are applied (and the ignition cut) when all you are trying to do is open the door, lean out and see exactly what you are reversing into.
It does seem that most electrical systems release the brakes automatically at just the right moment to allow you to move off smoothly, even uphill (with a bit of practice) – which you might expect to be a difficult operation to program in. And at least this would mean an end to my occasional experiences of driving off and feeling that the car isn’t quite pulling as it should do (until I notice the warning light)! But really, to me an electric ‘handbrake’ is simply an unnecessary extra bit of technology that could go wrong. Not to mention being likely to get you out of the habit of using an ordinary handbrake in other cars.
Item: old tyres. What I mean is that I want my next car to have worn-down tyres, so I’m not tempted to keep them. After all, they might easily have been damaged internally by being driven up on to kerbs, down into potholes, or when under-inflated. Far better, it seems to me, to replace the tyres immediately you acquire a used car.
But what a minefield I shall have to tread (sorry)! There’s a new EU label on all tyres which gives the manufacturer’s rating for fuel economy (ie, low rolling resistance), braking grip in the wet, and external noise. But what about how loud they sound from the driving-seat? Their handling in the dry, and on bends? Their likely lifetime in terms of miles? And how quickly the performance falls off as they wear?
Even Which? magazine, which prides itself on its thorough testing of tyres, doesn’t distinguish between them on this last count, merely warning that road grip will reduce “well before the tread depth reaches the legal limit of 1.6 mm.” (As will the ability to channel water away from where the tyre is in contact with the road, surely.) And yet Which? then compares all the tyres on test for their estimated lifetime mileage right down to this tiny depth, as if encouraging you to go for it: how perverse is that?
Not that I shall be selecting (and spending extra on) my new tyres to get the maximum mileage – where’s the advantage in this, when I might suffer a puncture at any time and then feel that my investment is forcing me to have it repaired, when I would be safer with a replacement tyre? The other aspect is that all tyres start to deteriorate after a while, and should be replaced before they are ten years old. Hence if your annual mileage is low, long-wearing tyres are no benefit for you.
And curiously, they deteriorate faster when not in use (especially if being exposed to the elements). The reason is that the rubber contains preservative chemicals that only get released to do their stuff while the tyre is being flexed. Because of this, the maximum age you should allow a spare tyre to reach (if it’s not been used at all) is six years. So do you know how to find and read a tyre’s production date? Look for the word DOT on the sidewall and then, to the right of it, four digits (possibly in an oval). For example, 4506 means Week 45 of 2006: if it’s your spare tyre, scrap it now! But I must finish off my wants-list...
Item: if my next car comes fitted with an audible warning of the distance to an obstacle behind when I’m reversing, I would like this feature to work not in reverse gear when required. After all, I could be facing uphill and aiming to roll gently back on the brakes into a tight parking position, in neutral. I wouldn’t want to have to select reverse and risk a sudden lurch, just to get the warning signal.
If all these wishes of mine are met, I shall be well pleased. You may recall from last month that a particular requirement is auto-gears, so ought I also consider the option of an electric car – the ultimate no-gear-change vehicle? The trouble is, every other month I seem to see alternating good and bad news about the future prospects of this catagory, and the good doesn’t cancel out the bad in my mind: I experience ‘range anxiety’ just thinking about electric cars, so I don’t know how their owners cope with it! And like most drivers, I sometimes have to make journeys that are well over the nominal 100 mile range. So electric is out.
Now, did you notice a linguistic error near the start of this column? I left it there (as a talking-point) instead of going back and correcting it after I looked it up out of curiosity. I’m referring to the first “Item:”. I always thought that when used like this, it was short for “Here’s an item in my list.” But in fact it’s the Latin word item, meaning “also” (which I suppose I ought to have remembered from school Latin classes 55 years ago). Hence it should only be used in a list against the second and subsequent, er, items. My mistake was to use it for the first one.
Over time, “item” also became an English noun of course, meaning first anything that was in a list and then, well, anything at all really. It’s hard to think of another word (except perhaps “thing”) that does this job so well ... just as I can’t yet imagine another car suiting me and my driving as well as my Corolla has done for twelve years!
Peter Soul
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