I'll say it would be great for YS to come out with a 200 CDI. They could probably take the example of saito with it's FG36. Also even if the YS happens to be a coulple oz more (about 5 oz max) flyers could use smaller fuel tanks (making fuel tank placement easier ). All they need to do is increase the bore of the 170, add a walbro carburator and there you have it.