Tested: Maxima Bio2 Two-Stroke Oil

Good for your two-stroke and better for the environment.

two-stroke engine oil, premix

Poor fuel economy and far too much unburned gas and oil going out the exhaust caused two-strokes to fall out of favor a long time ago, but some of us still love the simplicity, the sound, and, yes, the smell of bikes that put down a power pulse every time the piston descends in the cylinder.

There's not much I can do to reduce the amount of unburned fuel in the fog that streams from the stingers on my two-stroke streetbikes , but I'm doing what I can about the toxicity of that haze by using Maxima's Bio2 two-stroke oil. Bio2 is an ester-based synthetic lubricant that Maxima says is biodegradable and "recommended for use in environmentally sensitive areas." Most of my leisure rides pass along the beach and through various coastal ecological reserves, so running Bio2 in my oil tank makes me feel just a little less guilty. It's like ordering a side salad with my bacon double cheeseburger.

Bio2 is suitable for premix or injector use and contains loads of anti-scuff additives and special ingredients meant to reduce friction and prevent carbon buildup. And thus far it seems to be doing all of that. I inspected the top end on a recently rebuilt engine after breaking it in on Bio2 and the pistons and cylinders look excellent, while there was just a little oil residue inside the exhaust headers and on the spark plugs. Bio2 is said to be clean burning but still contributes to a pretty thick cloud behind me when I ride, and while Bio2 doesn’t smell as wonderful as Castor 927, it makes for a pretty pleasant aroma that any vintage-bike fan will appreciate.


Price: $22 for a 1-liter bottle
Contact: maximausa.com


Verdict: Good for your two-stroke and better for the environment, but a bit pricey and not as sweet smelling as old-school oils.