Remove the cover, four nuts on the sprocket and remove the metal retainer on the axle against the sprocket (split washer).
Adjust the sprocket of the chain
120 chain link
Sprocket and chain and what?
with a standard 17t front sprocket and a 42t rear sprocket the standard chain size is a 525 ( x-ring or O-ring) 124 link.
Take off the chain and then there should be 2 little bolts holding on the sprocket. Remove those and then rotate the sprocket slightly so its teeth line up with the teeth on the output shaft and it will slide right off.
Pull the head and remove cover on clutch side of motor loosen and rotate mortar pull chain out threw bottom with sprocket
take the timing chain cover off and with a wire hanger pull it from the bottom to the top sprocket so it doesn't fall.
A chain breaker tool is the best tool to use for removing a stubborn drive sprocket from a motorcycle chain. It is specifically designed to break and remove chain links, making it easier to take off the sprocket.
The chainring by the pedals and the sprocket(s) by the rear wheel.
A minimum plain bore sprocket is a roller chain sprocket with a hole drilled through the center. A finished bore sprocket is a roller chain sprocket with a hole drilled through the center augmented by either a keyway or set screws.
Normally that indicates a worn out sprocket. Replace and you should be OK.
Both, cranshaft to camshaft sprocket, belt, camshaft sprocket to cams, chain.