Re: 100:1 Mix
ckangaroo has hit the nail precisely on the head. Unless you know how to tune for a lighter oil/fuel ratio (don't run lean) you should be extremely careful going from the standard 32:1 2 stroke mix to the 100:1 Opti-2 oil.
Here's how I would suggest to make the change:
Mix your fuel at the Opti-2 recommended ratio and run your bike but keep a close watch on your plug and engine heat. I might even suggest that you richen your fuel to air ratio (lower your 'C' clip) at first and do a few plug chops to see where you're at. A word here about spark plug color. It has been my experience, and a few other Opti users, that the plug might take on a grey color as opposed to the normal tan to dark brown most are used to seeing with other oils. If this is the case then disregard what you've read about a chocolate brown being the best and look for a darker shade of grey. Very light grey, almost white means you're heading for trouble. Keep it rich until you've established a good plug color and you should be good to go.
Now this brings us to a discussion about breaking in from day one on Opti-2. I and many others have done it with great success. I know you've probably read that engine manufacturers warn against using a synthetic for break in saying that the rings will never seat properly. I have to disagree based on experience and yes there's going to be opposing view points on this with people posting quotes from manufacturers and experts but the facts speak for themselves. Properly tuned, an engine can be successfully broken in on synthetic oil. Which takes us to the next topic:
If you go back to the first page or so of this thread you'll find some posts from me about an older engine that for what is still and unknown reason, lost power when it was switched to Opti-2 from a good quality 2 stroke oil. When that oil was used the engine regained it's original power. That engine was my first and had accrued high milage and never performed as well as later engines that I've had. It is retired today and hangs in my garage. It still runs good, starts easy and idles great but does not hold a candle to 3 others I currently have. My contention is the pistin rings never seated properly (the compression is much lower than later engines) and the reduction of oil further compromised the compression. All theory except the compression issue. Remember that engine was broken in on 2 stroke oil @24:1 then 32:1 Stihl 2 stroke oil for air cooled engines.
I ride with other Denver bikers and any of them will attest to the power, speed and smoothness of my Opti-2 engines. Maybe one or two of them will step in and comment.
With all of that said let me AGAIN say that I do not suggest you change your current oil choice. Using Opti-2 at the recommended mix ratio is a personal choice and those who feel uncomfortable with it should stay with what works well for them. Opti works for me and that's all that really matters. Everyone, no matter your opinion should always do/use what you feel works best, for YOU.
Have fun, ride safe.
Age and Treachery Will Always Triumph
Over Youth and Skill & "Charlie Don't Ride"