You can "fix" that poorly made single points cam. It takes an afternoon of filing and wet stoning the approach ramp on the lobe that fires first to pull it into sync with the other one. But, it's all rather pointless. What you will discover is the XS650 points set wasn't designed to do double duty like this and wears quickly.
So, I did just this with my dual lobe cam. It helped a lot, and I think I need to cut it in a bit more is all. I think I'll try this before I move on to anything else. I like the minimal hardware design of it. I'm just tired of the slight out of time lobe in the cam and thought a TCI of some sort would be easier and more reliable. Thanks for the reminder, i think you've got the best idea in just fine tuning this set up!