Reasons why motorcycles can spontaneously catch fire.

The fire at the Carina apartment building in Ho Chi Minh City caused significant loss of life and property. The initial cause has been identified as sparks from a SYM Attila scooter. The reason for the scooter spontaneously catching fire remains unknown, with no conclusion yet reached by authorities. According to motorcycle experts, it is very rare for parked vehicles to spontaneously combust, but such rare cases do occur.

According to Mr. Le Hoai Sam, chief technician at a Piaggio dealership, the fact that the vehicle caught fire without starting is most likely due to an electrical short circuit. A short circuit occurs when the positive and negative terminals of an electrical source come into direct contact with each other without passing through a power-consuming component (resistor). The positive wire of the battery coming into contact with the vehicle frame heats the wire and contacts, leading to the burning of the wire insulation, which then spreads to the plastic parts.

The initial investigation into the fire at the Carina apartment building has determined that it was caused by sparks from an Attila motorbike.

This phenomenon often occurs in older vehicles where repairs are not done carefully, leading to exposed wires. Alternatively, the wire insulation may degrade or become brittle after prolonged use, easily coming into contact with the vehicle frame, causing short circuits and fires. The first part to burn is the wire, and it takes a considerable amount of time for the insulation to burn.

Specifically, during repairs, the vehicle may need fuse replacement, but these may not be of the correct specifications or function properly in the event of a short circuit, leading to a fire hazard. Newer vehicles have a better fuse system, as it's divided into multiple points. In the event of a short circuit, the fuse in that area will immediately trip, minimizing the spread to adjacent areas and reducing the risk of fire.

Mr. Do Manh Hung, a technical expert at Honda Vietnam, shares a similar view. “Normally, when the ignition is turned off, the battery and the wires to the ignition still have power, but it goes through the fuse. If there’s a short circuit, the fuse will blow. However, if the fuse is replaced incorrectly or additional equipment is installed improperly, fire and explosions can still occur,” the expert stated.

Fuel injection technology also affects the likelihood of spontaneous combustion, depending on whether the vehicle uses a carburetor or electronic fuel injection. According to a motorcycle expert, if it's a very old vehicle using a conventional carburetor, the risk of ignition from a spark is higher and more dangerous. Newer vehicles using electronic fuel injection are less likely to experience fuel leaks.

Experts also shared that vehicles equipped with accessories such as anti-theft devices can also catch fire. Often, incidents occur due to careless installation by technicians at connections and wire windings, causing contact with the ground wire, leading to a sudden short circuit and the risk of fire.

Vehicle owners should have their cars serviced at reputable, authorized dealerships. Large dealerships have stricter controls over repair and maintenance processes, ensuring higher safety standards. However, even in engineering, unforeseen accidents can occur, such as rodents gnawing on wires or the deterioration of electrical insulation over time, leading to contact with the vehicle frame and short circuits.

In the past, there have been quite a few cases of motorcycles spontaneously catching fire, all while in motion on the road. The SYM Attila model itself has also been reported to have experienced incidents where the connection between the battery, charger, and trunk light was damaged by a motor, causing the plastic and rubber-coated connector to burn and the entire wiring system on the right side to melt.