I've focused my fuel economy efforts on my daily commuter vehicle... my 2005 Suzuki Boulevard C50 motorcycle. It's an 805cc, liquid-cooled, wet clutched V-Twin. I'm currently averaging 51.3MPG.
I've been "running some tests" with fuel additives, specifically StarTron, Sea Foam, and the Lucas Oil stuff.
For my "tests," I've maintained my riding habits. I had an established baseline for additive free riding running E10. I only get my fuel from a WaWa station near my house or from the Shell provided Navy Exchange station near my work. Both provide 87 octane E10.
First "test run" was using StarTron. Duration of this test was 1 bottle of StarTron. I calculated out how much to add, initially, based on my 4 gallon tank. On each successive fill up, I added based on 3 gallons going in as I always fill up at this point (which coincides with my low fuel light coming on). Once the StarTron was gone, I ran for 10 straight E10 fill ups. (This gives me the A-B-A test concept.) Results... No noted increase in efficiency. Cost of the additive outweighs fuel savings.
Second test run was with the Lucas stuff. Same routine, except I was, obviously, adding the Lucas stuff vice StarTron. This test lasted through 2 bottles of the Lucas additive. Results... No noted increase in efficiency. Again, cost of additive outweighs fuel savings.
Third test, same agenda, using SeaFoam. Duration, 1 bottle. Results... Same as first 2 tests.
Now... aside from the gas price variable, can anyone think of anything I might have done wrong that would give me negligible improvement? Based on my "tests," using additives is simply dumping even more money into my tank.
Yeah, additives only help by cleaning things up.
Is the 87 octane the recommended octane? If premium is, you can try running that. Gains should be likely. Not spectacular, but enough to cover the price difference.
Yes, 87 is the recommended fuel. Anything over 87 would be a complete waste since the bike only has a 9.4:1 CR. Minimal chance for pre-det at that low a CR.
Given the fact that I have seen no improvements with any additives, and the fact that fuel doesn't stay in the bike's tank for long, the fuel system is pretty clean.
I think I'm done throwing money at additives.
I would try some Torco GP7 1cc per three gallons and or Acetone 1oz per three gallons.
The Torco lubricates the fuel system and top end and improves combustion.
Acetone absorbs water and improves combustion with better fuel vaporization.
I tried Lucas and StarTron and my engine ran worse.