Re: motorized bike only starts with starter fluid
Try using the choke and if you have the NT carburetor you can try a three second shot with the tickler button. That button simply sinks the float and overfills the carb for a rich condition that can make cold starts easier.
Pedal up to about 10 MPH, release the clutch lever and keep pedaling until the engine starts. Disengage the clutch and let the engine run a few seconds, giving it a little throttle then open the choke. If you have good ignition the engine should start and run properly using this method.
If it starts using starter fluid you just need to find that 'sweet spot' where the engine starts easily. It might take some experimentation but eventually you'll discover what your engine wants/needs to start without using any outside aids.
What spark plug gap are you using? .024 to .028 is a good starting point with a stock engine and most plugs. You can play with the gap later to see what works best.
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