Understanding Car and Bike Starters: The Role of Gubbins and Engagement Mechanisms
The internal components of car starters may seem like a zoo of moving parts, but each component serves a specific purpose. In this article, we will explore the intricate systems found in car starters and why bike starters may differ. We'll uncover the role of solenoids, planetary gears, one-way clutches, and other mechanisms that ensure efficient and reliable operation.
Car Starters: A Closer Look
Car starters are known as pre-engaged machines. This means they have a system that moves the drive cog onto the pinion as the engine is started. This process is not just about engagement; it also involves switching the current required to start the engine and converting it into mechanical energy to turn the motor.
Each component within the starter plays a crucial role:
Solenoids
The solenoid is a key component in the starting process. It is responsible for generating a powerful magnetic field when activated. This magnetic field pulls the starter drive mechanism onto the flywheel, ensuring a firm engagement. Once the engine is running, the solenoid releases the drive, returning to its initial position.
Planetary Gears and One-Way Clutches
The planetary gears and one-way clutches work together to manage the meshing of the starter drive and the flywheel. The planetary gears ensure a smooth and synchronized engagement, while the one-way clutches prevent reverse rotation and free-wheeling.
Helical Things and Disengage Pins
The helical thing referred to in the original text is likely a helical gear, which helps in the transmission of rotational motion from the starter to the flywheel. The disengage pin is a mechanism that ensures the starter’s drive can be disengaged once the engine starts.
Bike Starters: A Different Kind of Engagement
Bike starters can be more varied in their design, with some emulating car starters and others featuring unique mechanisms. For example, the author mentions that his old air-cooled BMW and Moto Guzzis had car-type pre-engaged starters, similar to those in cars.
However, most bike starters are designed differently. Rather than pre-engaging the drive cog onto the pinion, they may use a freewheel system. This system allows the starter’s drive cog to turn the motor. Once the engine starts, the starter’s cog is forced to turn faster than the starter, resulting in the starter motor spinning freely and no longer turning the engine.
Freewheel Systems
In freewheel systems, the starter’s drive cog is allowed to rotate without driving the engine. The freewheel mechanism ensures that the starter cannot drag the engine, which would otherwise stop the starter motor from turning. Once the engine starts, the starter’s cog is spun faster than the starter due to the resistance from the running engine, causing it to spin freely.
Historical Innovations and Their Limitations
Some older systems utilized the dynamo as an electric starter. This was an elegant solution, as it combined power generation and starting functions. However, dynamos were not as powerful as alternators and did not produce strong starter motors. They were suitable for low-compression two-stroke engines like the 1970s Yamaha 200 but could not reliably start four-stroke engines.
Modern bike starters are more reliable and efficient, often using high-power electric motors that can handle the demands of four-stroke engines. As technology advances, bike starters continue to evolve, incorporating advanced electronics and materials to improve performance and reliability.
Conclusion
The inner workings of car and bike starters are complex but fascinating. From solenoids and planetary gears to freewheel systems and one-way clutches, each component plays a vital role in ensuring that these essential machines start reliably. Whether you're a beginner or an experienced mechanic, understanding these mechanisms will enhance your appreciation of the engineering that keeps our vehicles running.