Motorcycle riders do not necessarily need to rev up their engines while idle. However, some riders may choose to rev the engine occasionally for various reasons.
One reason is to warm up the engine, especially in colder weather conditions. Revving the engine for a short period of time can help raise the engine's temperature and improve its performance before riding. However, modern motorcycles are designed with advanced fuel injection systems that can automatically adjust the engine's parameters for optimal performance, so extensive revving is not required.
Another reason riders may rev their engines while idle is for attention or to signal their presence. The sound of a revving engine can be attention-grabbing and may help alert other drivers or pedestrians to the motorcycle's presence. However, it's important to note that excessive or unnecessary revving can be considered a nuisance and may be subject to local noise regulations or even legal consequences.
In general, it's best to avoid unnecessary revving of the engine while idle to minimize noise pollution and reduce unnecessary wear on the engine components. Motorcycles are designed to operate efficiently and reliably without constant revving, so it's generally recommended to allow the engine to idle smoothly without excessive revving unless specific circumstances call for it.