Gasoline and Octane: Motorcycle Go-Juice
“Gasoline” in America. “Petrol” in Europe. “Benzine” in Scandinavia, Russia, Germany, Israel and Bulgaria. They’re all different terms for that favorite motorcycle go-juice we hose into our tank.
Except for a few electric bikes and any other alternative energy two-wheelers that may be in development, the vast majority of dirt bikes, MX bikes, cruisers, standards, sport bikes, sport tourers, luxury tourers and all other bikes drink up as much as you can give ‘em and then shortly thereafter demand some more. Some may sip the juice lightly, such as a moped. Others, like drag bikes, guzzle the stuff for a few seconds into hyper-oblivion.
So what’s up with this juice?
You probably know it’s refined from crude oil, which is famous in engineering circles for its high-energy density. In addition, because oil is easy to transport, and is relatively abundant on our planet, this combines to make it pretty popular in our little world. In fact, it’s the most vital source of energy since the mid-1950s when it surpassed coal. (How efficient would your bike be running on rocks?)
Because motorcyclists are required to share the various crude oil derivates with cars, trucks, buses, boats, ships, airplanes and planetary industries, some countries even go to war when they get concerned about it.
Our famous go-juice starts out in its crude form slumbering within the earth’s crust for a millennium, dreaming about motorbikes of the future. Just about the time it starts to imagine that every niche permutation of a bike has been developed, the goo then gets drilled out of its long sleep to get cleaned up and put to work. First, it gets boiled and purified at a refinery. Then, a bunch of other chemicals get mixed into the juice to make our bikes happier (performance additives). Finally, it gets transported to gas stations all over the place so that you and I can show up and pump this highly refined concoction into our tanks.
Now what about those pesky “Octane” numbers? Aren’t those supposed to represent the highest price it sells for?
In a word: “Nix.”
Higher octane numbers do correlate to higher prices, but of course, we haven’t seen prices at those octane levels in a long time. Really, octane ratings are simply used to represent the anti-knock performance of our go-juice. In other words, if you hear some audible pinging from your engine, that’s its way of telling you to feed it some higher-octane fuel at the next pit stop. In most cases, all you need is the recommended gas that your manufacturer designates for your bike in your owner’s manual. For most bikes, paying more for premium gas is not money well spent. Some manufacturers do “require” higher-octane gas for certain bikes, in which case you would be wise to ante up at the gas station to keep your baby smiling.
Most riders in North America will be familiar with the following common octane grades.
- 85-87: Regular
- 89-90: Mid-grade
- 91-93: Premium
And if you happen to be in Europe thinking those are some low numbers, realize that although the numbers may be different across the pond, the octane is not. There are different ways to calculate octane, and in Europe a different octane rating calculation is accepted as the standard. Bottomline: Octane ratings in Europe are displayed at the pump about 4.5-5 higher for the same octane level in North America.
Regardless of what octane you use for your bike, one thing you want to be aware of is that gasoline, petrol, go-juice, or whatever you prefer to call it, does not store indefinitely. It deteriorates with age. Lighter parts of the mixture evaporate, leaving heavier parts to form deposits. This will cause gums to build up in the engine cylinders, as well as the fuel lines, which makes it harder to start the engine. Bear this in mind if you don’t ride your bike during the winter or any multi-month period. Petrol could become unusable in a few months or might become unusable after a year.
Hence, if you are planning not to ride for a few months, toss a fuel stabilizer additive into your tank. You can buy this at bike shops and auto stores. Use as directed, and run your engine to circulate the additive before storing your bike.
Perhaps in the future some other form of go-juice will be fueling our throttles. But for now, that gooey stuff slumbering in the earth’s crust is the fundamental power elixir for motorbike fun.
Posted: September 14th, 2007 under Riding.
Comments: none















Write a comment