Here's a picture that may help. The star shaped piece in the upper part of the photo is attached to shift drum. It has an arm that ratchets back and forth to change gears. Sometimes the phillips screw holding the star wheel on comes loose and lets the arm come off track, causing you to be unable to put the bike in gear. Attached is the link to the post I got the picture from, it also has a video of it shifting. Also don't forget to FIRST confirm the drive chain has not come apart and is lying bunched up in the chain cover. If none of this makes sense to you I'm sorry, but you need to take it to an experienced mechanic.
My son & finished his complete restoration and is was pretty complete. I've got a post in the project logs that was almost compete when we ran into a probelm. A couple of rides past the shake down and it came home ok but after we parked it - it won't go past Neutral. Now we did have an issue on...
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