There could be several reasons why your Pulsar 150's mileage has decreased drastically after repairing half the engine. Here are a few possible factors to consider:
Mechanical Issues: It's possible that there are lingering mechanical issues that haven't been fully resolved during the engine repair. This could include problems with the fuel system, air filter, ignition system, or improper tuning of the engine. These issues can negatively affect fuel efficiency.
Incorrect Assembly: If the engine repair wasn't performed properly or some components were not reassembled correctly, it could result in decreased fuel efficiency. For example, if there are leaks in the fuel system or air intake, it can cause fuel to be wasted or an imbalance in the air-fuel mixture.
Riding Style: Sometimes, changes in riding style can affect fuel efficiency. If you've started riding more aggressively after the engine repair, such as rapid acceleration, higher speeds, or frequent braking, it can lead to increased fuel consumption and lower mileage.
Incorrect Fuel Grade: Ensure that you are using the recommended fuel grade for your motorcycle. Using a lower octane fuel than recommended can impact engine performance and fuel efficiency.
Tires and Tire Pressure: Check your tire condition and ensure they are properly inflated. Improper tire pressure or worn-out tires can increase rolling resistance, which negatively affects fuel efficiency.
Environmental Factors: Changes in weather, road conditions, or traffic patterns in your area can also impact fuel efficiency. If you've been riding in heavier traffic or encountering more stop-and-go situations, it can lead to decreased mileage.
It's best to consult with a qualified mechanic or authorized service center to diagnose the specific cause of the decreased mileage. They can perform a thorough inspection, evaluate the engine repair work, and identify any underlying issues that may be contributing to the problem.