The long deadlines and the attempt to save money. Two reasons why motorists decide to independently replace summer tires with winter ones. Assembling bicycles at home is not a science, but some things need to be solved.
In the courtyard in front of the Auto Houser tire service in Roztoky near Prague, his manager Lumír Novotný is facing a complaint. On a red Toyota RAV 4, after changing the tires, the air pressure sensors did not pair with the ECU and the on-board computer reports an error. For a moment it seems that he does not know how to deal with the situation, when the owner of the car reveals to him that he has used wheels from another car. In this case, however, the entire pairing process must be done from the beginning. “Sometimes there are problems with the pressure sensors, each machine is a little different,” Mr. Novotný says dryly and hurries to serve the customers waiting at the checkout.
At the end of October, the tire repair shops are busy. Despite the warm weather, many motorists honor the date of November 1, when the obligation to wear winter tires begins. And the waiting times correspond to that. A week has passed here in Roztoky, in nearby Velké Přílepe, the Pneuservis u Milana family has offered us an appointment in ten days. The Mratín car service is closed for up to 14 days, as its owner Vladimír Trendl explains, saying he offers tire replacement as an additional service.
Even if a hever is no longer an obvious part of a car, one can always be found nearby. And every driver should remember the theoretical knowledge of how to change a wheel from driving school. So why not try it on the patch in front of the house?
At this point it should be noted that even in the case of changing wheels, the well-known adage does not apply.What you learn in your youth … Just as today we do not kill aphids with DDT in the garden, we too should not change without thinking about the wheels in a so-called cross, which was the recommended method to ensure uniform driving of all tires. Modern winter tires tend to have an arrow-shaped directional pattern, which has excellent properties on a snowy road. However, it may only be on the side of the car it was originally mounted on. These tires are recognizable by the arrow on the side, which must always point in the direction of travel.
In this case, the wheels can be swapped between the front and rear axles, but not from left to right and vice versa. “When amateurs change tires, this is one of the most common mistakes,” warns Lumír Novotný, who would advise not to change wheels at home. “It often happens that the shock absorbers on the front axle of the car do not work 100 percent and punctures form on the tire. When such a tire reaches the rear axle, it tends to be extremely noisy.”
The screws on the wheels are often stiff after six months of use, and an untrained motorist tends to lubricate them with something so that next time they are easier to loosen. Technical petroleum jelly is often such a lubricant. Although it is suitable for lubricating bearings, it can be dangerous in the case of wheels. Anyone who treats vines in this way shouldn’t be surprised if they gradually loosen during the season. “Reinforced screws can be sprayed with, for example, the WD spray, but I would only recommend copper paste for the treatment,” advises the head of tire service from Roztoč.
Perhaps the most compelling argument for changing wheels in a professional rather than on the street is the need to balance them. According to Lumír Novotný, this is necessary at least once a year, especially if the car has driven tens of thousands of kilometers during that time. “My experience is that after a season on the bike, usually something between five and twenty grams of weight is missing,” he says.
When it comes to smooth wheel balancing, Vladimír Trendl wouldn’t be so strict. “Many of our customers drive something like five thousand kilometers during the winter season. In these cases, I wouldn’t be afraid to skip the balance for once.” However, even a small amount of travel can be a problem for the bike if the car is driving on potholed roads or if the weight accidentally falls off the bike.
Amateur repairers should also invest a few hundred crowns in a torque wrench which will ensure that the screws are tightened with the correct force. To make things not so simple, each car manufacturer prescribes a different tightening torque, but it is usually around 120 Nm.
The optimal tightening of the screws should not be underestimated: if we tighten them too little, they can loosen during operation. In case of force majeure, there is a risk of tearing the thread.
