Re: Motorized bike clutch slipping
You didn't tell us what engine you have but we are assuming it is a Chinese 2 stroke, in-frame style with a manual clutch.
Noises are common and hard to diagnose from a description. If the clutch is slipping you should be able to feel it. The engine will increase in RPM but the bike doesn't move any faster. Starting would be a problem too if the clutch slips.
These little engines are famous for their sounds. Screeching is one but grinding could be a sign of something that needs attention.
Did you lubricate the gears on the right side and the clutch actuating parts on the left? The cam, bucking bar and ball bearing inside the left side sprocket cover (clutch actuator) need lubrication with a good grade of bearing grease. The gears too need grease but only a small dab smeared into the gear teeth. Too much grease and then your clutch will slip.
Hope this helps and...welcome to the forum. Glad you've joined us and hope we can help.
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