IT was reported that a roadside trader was killed by a runaway lorry tyre that came off a lorry at KM43 of Jalan Pantai near Bandar Permaisuri in Terengganu at about 5pm last Tuesday.
As it turned out, it was not just a tyre but double rear wheels.
Over the years, I have read countless reports of runaway tyres that caused grievous injuries or damage to other vehicles and properties.
If a tyre alone were to fall off from a vehicle at whatever speed, it would just fall flat and lay motionless on the road, or at the most roll and meander over a short distance.
But if a tyre were to be fixed to a rim and
fully inflated with air, the weight will
increase severalfold.
And if such a wheel were to be dislodged from a speeding vehicle, it would be extremely dangerous and uncontrollable.
Unlike lorries with brake failure that could easily be stopped by loose gravel or sand such as those placed in runaway truck ramps or brought to a halt by obstacles in their paths, a runaway wheel could easily bounce and roll over a great distance.
While conducting training for 1,000 Teksi 1Malaysia drivers in 2014, I put up my hand before telling participants to put up theirs if they do not know how to change a tyre after experiencing a puncture while on the road.
None of them did while my hand remained in the air, and I confessed that I could not change a tyre and then explained the difference between a tyre and a wheel.
As I ensured the spare tyre was always inflated, I have always been successful in using the spare wheel after a puncture.
Also, it is a good practice to inflate the road tyres every two or three weeks or at the very least monthly, and always before driving long distances. While a tube can puncture and deflate completely, tubeless tyres usually leak very slowly and may not be noticed until too late.
It is better to overinflate a little than underinflate. Although the result is a little bumpier, fuel consumption will decrease with less resistance, whereas the vehicle is difficult to control with soft underinflated tyres, especially when taking a sharp bend at a higher speed.
Worse, constant flexing of the side walls will heat up the tyre to such an extent that it could explode.
This often happened when vans operated by government departments were used for running outstation, driven by drivers lacking duty of care.
YS Chan
Kuala Lumpur
