Quite common...no bulletin, but polaris recommends drilling and retapping the shaft for larger 3/8" bolt.
The problem is that when the bolt is tightened it squeezes together the shaft, bearing, and gear. When the parts get hot during use they expand making them a larger size and push outwards on the bolt with more force. End result is a broken bolt. A larger bolt will be stronger but the problem is getting the shaft redone. A viable solution is to use a longer bolt and not torque it hard tight....just enough to lightly compress the domed washer. Very important is to have clean threads and permanent Loctite applied. The longer bolt will give more threads for the thread-locker to work on while leaving it "loose" will give room for expansion as the parts heat up...the domed washer will act as a spring.
The problem is that when the bolt is tightened it squeezes together the shaft, bearing, and gear. When the parts get hot during use they expand making them a larger size and push outwards on the bolt with more force. End result is a broken bolt. A larger bolt will be stronger but the problem is getting the shaft redone. A viable solution is to use a longer bolt and not torque it hard tight....just enough to lightly compress the domed washer. Very important is to have clean threads and permanent Loctite applied. The longer bolt will give more threads for the thread-locker to work on while leaving it "loose" will give room for expansion as the parts heat up...the domed washer will act as a spring.