Well, i'll try to keep this a bit short. I have in my shop a 2015 Cforce 500HO EPS that a friend has been working on for another friend. It all started with a very noisy clutch (failed basket hex)
He managed to get a new clutch installed, went to fire it off and it was a crank/no start unless you supplied fuel. He has spent several weeks chasing this problem in his spare time and I suggested he bring it to my shop.

We got it running (couple of corroded connections were the cause) But as soon as it started I heard a noise in the engine that deeply concerned me. So I break out my stethoscope and in a few seconds determined the noise was in the top of the engine.

We removed the cam cover and discovered the intake rocker shaft support on the left was broken. No pieces found in the engine and we suspect it was broken a long time ago. (He states, the clutch was so noisy that it was scary hence why it got replaced)

So now we are on a mission to find a replacement head. I can say that from where it broke that it is definitely a design flaw.

[2015 Z Force 800 53/Trail EPS]

There has been more then a few of those. I think they updated that head though.