How do I De-Restrict a PW80 Yamaha?
- 1). Move the motorcycle to a hard level surface, such as a concrete slab or driveway.
- 2). Secure the motorcycle upright, using the center-stand or kickstand. Allow the engine to sufficiently cool before making modifications to the motor.
- 3). Disconnect the black spark plug wire from the engine's spark plug, located on top of the cylinder head, directly behind the front wheel.
- 4). Remove the two bolts securing the exhaust pipe flange to the bottom front portion of the engine.
- 5). Lower the exhaust pipe down slightly, to expose the circular restriction ring located within the inside portion of the exhaust pipe flange.
- 6). Remove the large gasket ring from the exhaust flange, followed by the circular restriction ring.
- 7). Insert the gasket ring into the exhaust pipe flange. Line-up the exhaust pipe flange with the engine's exhaust port, replace the two bolts and reconnect the spark plug wire to finish the process. Be careful not over-tighten and strip the exhaust flange bolts when securing the exhaust system to the motor.
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