I need some help from the pros...

So I'm riding along on my motorized bicycle around mile 50 from new with no problems so far. All of a sudden the motor dies and rear wheel locks solid. I lock cluck and peddled home. Upon removal of head and cylinder I say some scoring but nothing that said "hay I just locked your bike up". I removed the clutch cover and found debris in the cover. So I belive something jammed the clutch\crank gears but what. I haven't remover the clutch gear drive shaft yet. I'm running 93 octain 16 to 1 semi synthetic marine oil. I extensively cleaned and gasket matched the top end. Any suggestions would be great.
 
Re: W.t.f. I need some help from the pros...

So you pulled the right side cover and found...? You said some debris, but did you see what was causing it to lock up?

Did you put a dab of grease on the gear teeth before running it? Did you clean out the fibers from the clutch? Mine was chock full of clutch fuzz after a few minutes of operating. I blew it out with compressed air and some brake cleaner, then reapplied new grease to the gears.

Can you turn the engine over with a socket and ratchet with the clutch disengaged?
 
Re: W.t.f. I need some help from the pros...

So you can see that something got between the back of the clutch plate and the engine block. I belive the debris from this jammed the crank and drive gears and locked her up. Now when I got it back home I cycled it backwards and when i went forward it "seemed" to free it up. I just can't resemble it with out knowing for sure what caused this. All screws in the clutch housing are tight and with out scaring. Also is it normal for the wrist pin bearing to float outside of the connecting rod top end. No obvious damage is found but I thought it to be funny while removing the piston that the bearing didn't stay centered in the con-rod.
Thanks for any and all input. I'm actually happy about this for I will really know these little motors even better.
 

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there is discussion here somewhere from a couple years ago about wrist pin bearings that were a bit short to stay where one expected them to stay

looking at marks on case, I'd guess that the clutch hub was forced a bit crooked on the shaft taper (maybe key was stuck) - if metal debris got into hub bearing, then that may become a problem soon - I'd either replace it or wash it well in solvent & keep an eye on it
 
Thanks for the info man. I do believe it was just some piece of foreign metal in with the clutch assembly that ultimately. In between the clutch and crank gears and jammed them. There was actually a little bit of metal crushed into the gears. When the gears jammed up when I was going down the street I'm willing to bet that probably cause the flight out of alignment of the clutch does rubbing on the crankcase. I'm going to clean up real good put it back together and run it till it blows.
 
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