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I grenaded the piston on my wheelie boy rescue YZ250 (2013). The piston pieces went all down in the crankcase and the rest is history. I replaced the main bearings, main seals and crank with all OEM parts. I had the cylinder punched out and ported and started the reassembly process. It has been a long one to say the least.
The first time I put it back together, I didn't have the shift drum rotated far enough back to help the main shaft fall in and resulted in a little binding. I split the cases again and fixed the issue. The second time around I could not get it to shift. The transmission moved great but the shifter would barely move. Tore it down and realized my buddy had let a gear fall off the main drive shaft and put it on backwards. Flipped that gear around and everything dropped in just fine. The shift drum moved and the gears moved just fine before I put the cases back together. Now the shifter moves like it should and there is no binding but it will not shift up and down gears. If I turn the clutch, the crank and transmission spin but if I turn the countershaft, the crank does not spin. Spinning the crankshaft does not spin the transmission either. I am pretty mechanically fit but this has me getting really frustrated. Any help?