Setting timing on a 225??

Now I'm just curious. I don't know a lot about timing, but 14-18 degree's BTDC is firing the plug a little soon isn't it?

Advance the timing to the ping at WOT and then back it off 2 degrees and see what you think of it.
Of course you will have to set your idle down when you do it because it will speed up when you bring up the timing.