I posted this issue many months back. Motor would not exceed 4200 RPMs. Over time I replaced the control module, voltage regulators, shift sensor, and oil reservoir cap and battery. Carbs had been rebuilt and the fuel pump was rebuilt. Temp sensors ohm'd correctly. None of these corrected the issue. What was confusing was I could unplug the sensor plug from the control module and the motor ran perfectly to 5300 rpm. But when unplugged I had no sensors, so I installed a pressure gauge and a temperature gauge to make sure I knew what was going on. I tested the voltage at both idle and 2500 rpm and noticed that it exceeded 16V with is the limit for this motor. These were CDI voltage regulators. I also replaced the control module with a CDI module. No change. Ended up replacing the control module with OEM module and voltage regulators with OEM.
No of these fixed my issue. In the end what was it that fixed my motor? Can you guess? I only post this because I have noticed many time people post their problem, but then we never know if they got their issue resolved.
No of these fixed my issue. In the end what was it that fixed my motor? Can you guess? I only post this because I have noticed many time people post their problem, but then we never know if they got their issue resolved.