Hi everyone! Here’s my issue. I bought a 94 bayou 400 4x4 non running. I recently took everything apart because after putting a carb on it I was having issues with unusual sounds inside the engine. So I pulled the engine out, completely disassembled and found a lot of damage to the transmission gears and shift forks.

obviously I can’t buy new parts anymore, so I bought a complete used gear set that was in surprisingly good shape. Carefully reassembled everything with new gaskets seals bearings. Got the engine back in and it starts and runs so great. The issue I have is I have a random grinding noise that seems like it appears at the 4th shift so third gear.. it’s very intermittent, does not happen every time under the same conditions. I pulled the front drive shaft and no change to the noise.

about the only thing I really didn’t do much with was the gearbox on the left side that drives the front and rear prop shafts. Does anyone have any common issues with these bikes that I can look for a problem? This one has me stumped! I added a quick video of when we were able to capture the sound.

thanks in advance!