Buddy and I noticed our bikes seemed to be a little off in performance during a ride from Tucson to Bisbee. My bike was down in power and the MPG was way down. He has a 2010 Limited and had filled up at a Fry's station in Tucson and I had filled up at a QT. On the way back we stopped at a Shell and, for whatever reason, that gas seemed to wake up our bikes. My bike had better power and my MPG got a lot better. We're thinking we got some bad gas but from two different stations? Is Shell gas that good or the other gas that bad? Could we have been victims of a too low octane coming out of the high octane pumps?

 

Shell gas is Top Tier and has additional detergent additives, as compared with Brand X gas.

I won't run anything BUT Top Tier gas in my bikes. Around here that means Exxon, BP, and the (rare) Shell.

 

Yep agree with the Top Tier gas. I used to work with a guy who once said while we were all talking about gas we used for some reason...."I wouldn't put (insert brand X gas name here) gas in my lawnmower".

 

I can still remember when the mid-60's 427/435 Corvettes would only run on white pump Chevron. That really doesn't have anything to do with anything but any time I can remember anything I get excited and want to let everyone know. "Way to go!" to me.

 

Although you and your buddy bought "bad" gas at different stations, it may have come from the same supplier. Bad gas isn't such a big deal for modern engines, but in the old days it really sucked.

 

Maybe you got a load of Pemex from Nogales.

 

There are different levels of quality in different brands of gasoline. Octane ratings for gasoline ( as well as Reid vapor pressure, and many other things) are things that are measured to comply with Gov't regulations.
The one thing that you refer to: more power & better fuel range, are a result of add'l BTu's in the gasoline. This IS the fuel's energy content. You have just discovered that "cheap" gasoline actually costs more because of the substandard fuel range they provide. They don't burn as cleanly either, leaving more deposits on combustion surfaces.
"Top Tier " fuels are preferred for this reason.
So, now you know that buying "cheapo" gas at a Quickymart isn't the bargain that they make it out to be.

 

You guys just went through monsoon season could the off brand stations tanks had some water in them, octane usually doesn't make that much of a noticeable difference dirty fuel will.

 

Hmmm. I've used Mobile 91 in my Fat Boy since buying it. Wonder if Shell is any better. I used to have a pal who was an executive with Mobile and he told me that Mobile was top tier gas. Anyone have opinions on that.

My Fat Boy runs fine on California Mobile 91 gas although I notice that I only get about 35 MPH in city riding (maybe 40 or so on long Freeway runs). I'm imagining that this is due to all the California additives.

 

May not be the quality of gas.

You went from approx. 2400 feet elevation to around 5500 feet. Mostly uphill with thinner air will definitely affect performance and mileage. On the way back, mostly downhill and more oxygen in the air.

We change elevations quickly coming out of Phoenix going north and the effects are noticeable.