I don't think anyone makes a case saver for production, do they? I have photos of ones I have seen that guys have made up, but not that anyone has ever made just to sell.

Chain tensioner seems to be a good idea.

SnowDrift

 

maier plastic makes metal ones for lt/kfx 400's

 

I'm not sure if a case saver would help. If you have ever replaced the chain on one of these you might understand. As you or in this case the drive sprocket feeds the chain through it piles up on the case guide or even the plastic case saver. As more and more is fed it pushes through the case. I've seen two that have split right in half by the sprocket as it pushes more through. I put a tensioner on hoping to prevent this a little, but when you lose a master link that is just SOL.

 

Ouch!!