The points made by Mr Ramamurthy Mahesh Kumar in his letter suggest he may not be aware of regulations governing motorcycles (Racing in HDB estates adds to noise from motorcycles, Dec 28, 2019).
The two-stroke motorcycle is now uncommon. The most common motorcycles heard at night are four-stroke motorcycles, usually ridden by food delivery riders. Racing on Singapore's tight, heavily policed streets is highly unlikely.
Strict European regulations, which Singapore has adopted, are applied to both cars and motorcycles. These regulations govern sound levels from the factory floor.
Once they arrive in Singapore, they are again subjected to standards certification and annual inspections which deter any form of illegal modification.
Vehicle owners caught flouting the law are required to turn up for more frequent inspections to ensure they comply.
Aftermarket exhaust systems for cars and motorcycles are approved only if they comply with noise regulations. Even sports car exhausts are designed within decibel limits.
Where these regulations are more difficult to apply are on Malaysian vehicles. A number of them ply Singapore roads late into the night as many of their owners work in food and beverage establishments or on shifts. These are likely the cause of Mr Kumar's grievances.