Question One: What pre-mix ratio do you run and why? I have been getting different feedback from the Suzuki shop and other's saying 20:1 is not necessary due to advances in oil compared to when the bike was new and 32:1 is sufficient. Also, does anyone use a full synthetic or semi-synthetic pre-mix oil or just castor types?

Question Two: I'm looking for input on a break in procedure. I've done some research and found that most say a heat cycle type break in is best with progressive throttling & load on each cycle (http://www.off-road.com/atv/tech/two-stroke-engine-break-in-19350.html - http://www.duncanracing.com/TechCenter/2stkenginebreakin.pdf). I understand there are several ways to do this so I am simply asking for ideas with reasons, references and/or experience included please.

NEVER change premix ratio for break in. If you go from 32 to 20:1 you are taking fuel away and leaning the AF ratio. If you want to you can turn the pilot in so it won't idle and spits oil out the tail pipe, but you will need to repack the silencer after that mess. If you were jetted correctly, richen the air screw So it will just idle a d let it run until you feel heat in the cylinder. Do this 2-3 times progressively warmer. Then do a couple times blipping the throttle and get the engine up to operating temp. After that ride it constantly varying the throttle  a couple times. What your doing is lapping the rings for a good seal on the first couple cycles, excessive oil will not help. You need enough to lubricate. The next set of heat cycles is expanding and contracting the piston, it will shrink slightly after its been run long enough.  Too hard too fast will cause excessive wear on the piston and could give a poor ring seal if there is any blow by before the rings fully seat.
The harder you push your engine and the longer you tend to hold it at WOT determines the amount of oil you should be premixing. 500s 20-32:1 and 250s usually 32-40:1 with castor oils. I like 24 in the 500 and 32 in the 250.

is the theory that is best to  break-in with mineral oil tested ?

i run 927 and c-12 32:1 mixture in ALMOST everything. CR, LT Blaster

Does anybody have any experience with Bel-Ray synthetic oil? I'm using the MC-1, or the H1-R, whichever one is available locally. And since mine is an 86' with NO power valve, should I switch to the maxima 927 ?  I was mixing at 50:1 but now I'm going to try it at 35:1.

MC-1 is a name from the past just like Blendzall.

blendzall is made like 10 min from where i live. great product