i replaced the head on my 03’ sportsman 500 HO. It ran great in the garage and around the yard. Then I take it on the trail, i heard a metal snap and it stopped. I turned the key to start it again and nothing.

I opened it up at home and found the two bolts located on the cam shaft sprockets were broken. One was out and in one piece.

When I put the chain on the sprocket and I tightened the three bolts to Manufacture specs.

Now i have a cam with two broken bolts stuck in there and i have no idea how this (broken bolts and one loose bolt) happened.

Any thoughts or ideas would be greatly appreciated.