Sunday, 4 February 2007

Don’t believe everything you read.

I am going to assume that you know what, in the context of motor vehicles, I mean by a differential. If you do not, it might be helpful to read this article from

How a differential works.

As far as I am aware the only front-wheel-drive car without a differential was a racing car built by Walter Christie. This monster from 1907 had a 19 litre V4 engine set transversely driving the front wheels directly from the ends of the crankshaft. As you might imagine it did not enjoy any racing success and it was a long time before the idea of a transverse engine, driving the front wheels enjoyed commercial or sporting success.

Why does it matter? Because in the Sunday Times today I read Jeremy Clarkson’s review of the Renault Mégane Renaultsport 230 F1 Team R26 . Putting lots of power (the Renault has 230bhp) through the front wheels can cause problems, such as going straight on when going round a corner would be more useful. Clarkson explained that the way to overcome the difficulties of lots of power in a front-wheel-drive car is to fit a front differential. I would hope that most people would see that for the nonsense that it is and realise that any fwd car would be nigh-on impossible to drive without a differential (which must be a front differential in a fwd car). What he probably meant to say “limited-slip differential”, which has been used to mollify the behaviour of some powerful fwd cars and it may be that a sub-editor, ignorant of the technicalities of the matter, simply snipped the limited slip bit in order to save space.

If the error had been made in a specialist publication with a knowledgeable readership it would not matter as much but newspaper motoring sections attract a wider selection of readers, some might end up misinformed as a result of what they read. It is not serious in the great scheme of things if a few Sunday Times readers believe that the way to tame a powerful front-wheel-drive car is with a front differential and then make the logical jump that low-powered fwd cars do not have front differentials. It does however go against the grain, to my mind newspapers have a duty to educate and inform their readers which implies that facts will be reported accurately and truthfully. With Jeremy Clarkson entertainment is a key element of the writing. If the truth had been distorted for comic effect I could see a purpose to it. Unless the idea is to wind up people like me, who care about technical accuracy, I think I’ve missed the joke. If something like this can slip through the net then what other errors have been made in the past? What if a greater error is printed in the future?

The only remedy is to look carefully at what you read; does it fit in with what you already know? Does it make sense if you try to reason it from first principles? Are there other sources that corroborate it and what about any sources that contradict it? Above all, use your brain and don’t automatically believe everything you read.

Thursday, 1 February 2007

A Helping Hand

Have you ever wondered what it is like to use one of the orange SOS telephones? You know the ones, situated at 1-mile intervals along the motorway network as well as along many A-roads. It wasn’t something I ever intended to find out, although I was always curious, but the other day I had no choice.

I was driving down a dual carriageway on my way home from work. The accelerator pedal on my Citroën BX felt unusually stiff and erratic in its action and then, with a sad “ping” the accelerator pedal sunk to the floor. At the same time the car started slowing down, not what you want in the rush hour on a dual carriageway with no hard shoulder. At that point I spotted the lay-by ahead with its SOS telephone and I was able to cruise to a stop (my BX is an automatic so coasting really wasn’t an option; there are dire warnings in the handbook about freewheeling in neutral).

At first I tried using my mobile phone to contact the AA but all I got was a robotic female voice that I could not hear over the sound of the traffic. Realising that my mobile was of limited use I walked over to the box containing the telephone, opened the metal door, read the instructions and picked up the receiver. There is no dial nor any buttons to press, as soon as you lift the receiver the phone rings through to a control room somewhere. It seems that it is The Highways Agency who man the phones, I spoke to a chap named Steve who took my details including my AA membership as well as making sure that my car was off the main carriageway and did not pose a danger to traffic.

After giving my details Steve said that he would call back to tell me when the AA could get to me. He tried calling my mobile but I did not hear it ring, so he called me back on the SOS phone (it takes a while to realise that the phone is ringing when you don’t expect it). The news was not great, I was going to be waiting at least half an hour for a patrolman. The news got even worse when an AA patrolman called me on my mobile, from what I could hear he was in Cannock, in Staffordshire, a long way from Warwick where I was. Thankfully there was another patrol in my area but there was a slight mix up with my location, nothing serious although every minute standing around outside in the cold is a minute I would rather have spent at home.

Eventually the patrol arrived and after explaining the problem the patrol man set about examining my car. He quickly identified that the cable had snapped where it met the accelerator pedal and set about effecting a temporary repair. In a few minutes he had the cable attached so that I could drive the car but made it clear that it was a temporary repair that I should get fixed properly as soon as possible. I was actually way ahead of him; before even speaking to the Highways Agency or trying the AA I had contacted my local mechanic and told him my plight.

The patrol man followed me for a few miles to make sure I was able to drive without serious problems. The repair was good enough to get me home but it did leave the acceleration with an even more lumpy action.

This is not how I planned to open my blog, but I thought it was better to start with a story rather than a potentially tedious introduction to me and my life. I also wanted to thank the AA patrolman and Steve at the Highways agency. The garage fitted a new cable and also rebuilt the carburettor so my BX is now much better than it was before it went wrong. Thanks guys.