Fuel affecting Fuel Economy?

AJ · #1 3 Feb 2003

OK - so I'm no technical guru, but can the QUALITY of fuel significantly affect fuel economy?

Been travelling 2 months now and have ruled out as many factors as I can think of (wind, bike load, gradient, surface type and quality, tyre pressure and wear, riding and throttle style, speed etc) and yet occaisionally I still notice a fairly significant variation in fuel economy.

I'm on a DR250 (and fairly well loaded down) with only a 5.5L fuel tank so fuel economy takes up a significant amount of my daily planning! I've noticed that even under similar conditions on the same day (eg riding across Argentinian plains etc) the fuel economy can vary UP or DOWN with each refuelling (I've had rates of between 19 and 33 Km per L depending on all factors, the fuel factor can affect it by around 5 Km per L up or down).

Now, can the amount of ethanol or dilution be the cause; or could it be old fuel that isn't being sold promptly?

Just curious ....

Thanks,

Alex.

**RichLees** · #2 3 Feb 2003

I always get significantly (10-20%) better fuel consumption in France than in the UK. that's based on tens of thousands of miles on many different bikes. I put it down to fuel.

**harvey** · #3 7 Feb 2003

AJ,

The answer is yes. Low quality fuel (diluted, low octance, etc) will give you poor performance because the engine's not running as efficiently. Petrol does deteriorate after a while, so if it's old your fuel consumption will go up.

In India we were advised by the locals to use fuel stations that were busy because they were the ones with decent fuel. It's not uncommon in some countries, like India, to dilute the fuel with kerosone because it's much cheaper than petrol.

Harvey

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