Mike Cecchini wrote: ........othewise I use 95--110 leaded track gas that lasts for years with no harm at all.
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That's a controversial subject. I have some not so fond memories of another place where someone told everybody to use race gas in every other post he made.
The facts are, that in a lower compression motor (less than 10:1) any high octane fuel has more disadvantages than advantages, besides the cost.
Too high of an octane rating - which race gas or track gas has for a CBX - will result in unburned gasoline after the combustion which goes out through the exhaust but can also wash the cylinder walls and cause a lubrication failure.
The higher amount of ignition inhibitor additives will take some place away from carbon-hydrogen molecules, which are the energy carriers. The combustion in a lower compression motor is slower and colder. This may result in lower performance. We actually proved that in laboratory tests where the fuel with the highest specific density produced the highest horsepower. Race gas is not that fuel.
Finally, there is a theory that too high of an octane rating will also cause excessive carbon deposits.
All that does most likely not apply with different grades of pump gas and there should be no problem running premium in a motor that only needs regular - other than wasting money. But if you go into track/race gas of 100 plus octane, it may be a different story.
If I leave mine sitting for 6 weeks, it takes a carb overhaul to get it going. 
