800 engine dropped valve
A few days ago my Bombardier 800 Outlander's engine blew.
First indication was a substantial loss of power, and then a short time later, a horrific noise and the engine stopped. On disassembly I found both intake valves on the rear cylinder destroyed, one bent and the other broken off where the stem emerges from the guide. The loose valve head caused considerable mayhem within the rear cylinder.
The most likely scenario is that the timing chain to the rear camshaft jumped a sprocket-tooth or two which set the timing out and reduced power from the rear cylinder, and then jumped one or more extra teeth to put the inlet valves in the path of the rear piston.
Strangely, the only other Outlander owner that I know tells me he had exactly the same problem a few years ago. This coincidence makes it unlikely that we are the only two guys on the planet that this has happened to. We are both pretty fastidious about having our quads serviced by accredited agents - in fact mine was so serviced just a few running hours before the engine failure. My machine has 480 hours on the clock and my friends had about 260 at the time of his incident.
If anyone else has had a similar experience, or knows of one, I'd really like to hear from you.