Articles from Renkaankierrätys magazine
Weights balance tyres
When the steering wheel starts shuddering, it’s time to head to a tyre store. The steering wheel vibrates and seat trembles. A familiar feeling at 80- to 100-kilometre speeds for many drivers. As per usual with symptoms, you should not put up with them for too long; quick response to the problem spares the car and the driver.
“The problem lies with changes to the tyre balance. It is not only a safety issue, but also a factor that affects the durability of the car’s joints and tyres,”
explains Jukka Hölttä at Euromaster’s Kouvola branch. He highlights that when a driver notices anything unusual with the way the car handles, there is always a reason to suspect the tyres first. But what makes the correctly adjusted tyre balance change?
“Tyres wear unevenly and their surface changes. Rims may have come into contact with a curb or suffered from hitting a pot hole. Wet snow leaves the rims dirty. Those are the most common reasons.
Tyre balancing is not a new idea; it’s been done for years.” Hölttä stresses that weights are almost always needed. The rims alone cause imbalance due to their cast structure. Just like rims, tyres are unique too.
“Even when we take four tyres of the same make, from the same series, each of them will normally require a different number of weights.
The wheel balancer carefully defines the correct place and size for the weights based on the tyre and rim measurements. Clip-on weights are still used for steel rims, whilst adhesive weights are used for the increasingly popular aluminium rims allowing for the entire extensive surface area to be used.
The balancing is always done for the rim and the tyre together. In addition to the machine, the mechanic’s professional skills are invaluable.
“ The mechanic always checks that the tyre rotates properly, because even the machine does not always tell the whole story. The balancing is only finalized once the mechanic has checked the wheels.”
The need to balance tyres became more common as the front-wheel drive cars started to take over the market. With developing technology, new cars have become more sensitive and even the slightest changes are evident in the car’s performance.
“Tyre sizes have increased and low-profile tyres have become more popular. The importance of balancing is highlighted by low-profile tyres, and the weight quantity can be high.”
According to Hölttä, it is highly possible for the original balancing to stay correct for the entire lifespan of the tyre. He also stresses that the tyres must always rotate in the right direction.
“When a new tyre or rim is installed, the balancing must always be done again.
Renkaankierrätys 1/2015
Text: Vesa Vainio