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Five reasons to use motorcycle oil in your bike

You can use Car Motor Oils in your Bike if you Add Two More Wheels.

You wouldn’t want to buy a used bike if motorcycle oil wasn’t used.

Impressive performance happens when you are using the right oil in the right application.

Len Groom | TECHNICAL PRODUCT MANAGER, POWERSPORTS

The results of a study from lubricant additive manufacturer Infineum caught my eye recently. A survey of 1,000 bikers revealed that fewer than 60 percent are using a motorcycle specific oil in their motorcycles. Interestingly, more than three quarters of respondents think they’re using a motorcycle oil. Clearly there’s confusion in the market that requires clarification.

Let’s start with why you should always use motorcycle oil in a motorcycle engine. I’ll boil it down to five key reasons.

1) Motorcycles run hotter

In general, automotive engines are water-cooled. A typical automotive engine can reach 235ºF (113ºC) during operation, which is plenty hot. Motorcycles, however, run even hotter, particularly big, air-cooled V-twins, like your average Harley Davidson. They rely on air flowing across the engine for cooling, which is inherently less efficient at dissipating heat. This configuration poses additional challenges in stop-and-go traffic when there’s little airflow, particularly on hot summer days. In fact, testing of a 2012 Harley Street Bob in our mechanical lab demonstrated an average cylinder head temp of 383ºF (195ºC).

Heat that intense causes some oils to thin and lose viscosity, which reduces wear protection. High heat also hastens chemical breakdown of the oil (called oxidation), which requires you to change oil more often. In extreme cases, the bike’s temperature sensors can shut down the engine if it gets too hot.

2) High rpm destroys lesser oils

Motorcycles tend to operate at engine speeds significantly higher than automobiles. Your average metric sport bike easily eclipses 10,000 rpm. Some have even pushed 20,000 rpm. Your car or truck’s redline doesn’t even come close. The hydrocarbon chains get ripped to shreds.. You can feel the after-effects through the peg and handle bars.

High rpm places additional stress on engine components, increasing the need for wear protection. It subjects oils to higher loading and shear forces, which can rupture the lubricant film and reduce viscosity, both of which increase wear. High rpm also increases the likelihood of foaming, which can reduce an oil’s load carrying ability, further inviting wear.

3) Increased power density = increased stress

Motorcycle engines produce more horsepower per cubic inch than automobiles. They also tend to operate with higher compression ratios. Increased power density and compression lead to higher engine temperatures and increased stress. This places greater demands on motorcycle oil to fight wear, deposits and chemical breakdown.

4) Must also protect transmission – prevent viscosity loss

Many motorcycles have a common sump supplying oil to both the engine and transmission. In such cases, the oil is required to meet the needs of both the engine and the transmission gears. Transmission gears can shear the oil as it’s squeezed between gear teeth repeatedly at elevated rpm, causing some oils to lose viscosity. Many motorcycles also incorporate a wet clutch within the transmission that uses the same oil. Motorcycle wet clutches require a properly formulated lubricant that meets JASO MA or MA2 frictional requirements.

5) Storage invites corrosion

Whereas automobiles are used almost every day, motorcycle use is usually periodic and, in many cases, seasonal. These extended periods of inactivity place additional stress on motorcycle oils. In these circumstances, rust and acid corrosion protection are of critical concern.

While a good passenger car motor oil (PCMO) hits many of these performance areas, it doesn’t get them all.

PCMOs usually contain friction modifiers to help boost fuel economy. Furthermore, PCMOs don’t meet JASO MA or MA2 requirements. If used in a motorcycle, they can interfere with clutch operation and cause slippage. And no rider wants to deal with a slipping clutch. Likewise, motor oils have no natural rust or corrosion resistance. Instead, corrosion inhibitors must be added to the formulation, and typical motor oils don’t contain them.

AMSOIL Synthetic Motorcycle Oil is designed for the unique demands of motorcycles. It’s formulated without friction modifiers for precise, smooth shifts. It also contains a heavy dose of corrosion inhibitors to protect your engine against rust during storage. And it’s designed to resist viscosity loss due to shear despite intense heat and the mechanical action of gears and chains.

Ensure your customers are using AMSOIL synthetic motorcycle oil in their bikes for the best protection this riding season.

And people who use car oil in their bikes probably use the term “drive” when referring to riding.

Why Motor Oil Deteriorates

engine oil sludge can be prevented

Why Motor Oil Deteriorates

 

Like just about everything else, motor oil has a lifespan. Even the best oils eventually require you to change them. Historically, many motorists like the convenience of changing oil with the seasons, visiting the quick lube or pulling the ramps out of their garage each spring and fall.

Motor oil can deteriorate by becoming contaminated, the additives depleting over time or both.

How oil becomes contaminated

Base oils are the backbone of the finished lubricant that ends up in your engine. They can be conventional, synthetic or a combination thereof. They’re responsible for lubricating components, which reduces friction and protects against wear.

Base oils can lose their effectiveness over time due to a few different factors.

Oxidation – The interaction between oxygen molecules and motor oil molecules naturally leads to chemical breakdown. Just as oxygen causes a cut apple to brown or exposed metal to rust, it breaks down base oils and reduces motor oil’s effectiveness. Oxidation can lead to increased oil viscosity, which negatively affects energy efficiency. It also causes the formation of harmful deposits and sludge.

High heat – Today’s engines run hotter than ever before, with temperatures up to 235°F, and even higher if towing or hauling. The rate of oxidation for oil doubles for every 18°F increase in temperature.

Moisture – Your vehicle is also subjected to temperature swings, even when it is parked in the garage. Those temperature swings cause condensation to form inside your engine, leading to water contamination. Leaving a vehicle parked for extended periods or taking short trips that don’t allow the engine to fully warm up allow water to remain in the oil rather than evaporating and exiting through the tailpipe. Water can lead to formation of sludge.

Viscosity loss – A lubricant’s viscosity is its most important property. Viscosity has a direct bearing on wear protection, and your engine is designed to operate best using a motor oil of a specific viscosity (e.g. 5W-30). The intense pressure the oil bears as it’s squeezed between moving parts, like the piston ring/cylinder wall interface, can tear apart, or shear, its molecular structure, leading to viscosity loss. Suddenly, the 5W-30 motor oil your engine was designed to use is now essentially a 5W-20 oil, and wear protection may be compromised.

Fuel dilution – Fuel can wash past the piston rings and contaminate the motor oil, causing it to lose viscosity. Frequent short trips that don’t allow the oil to reach normal operating temperature can be especially problematic because the fuel won’t volatilize and exit through the PCV system. Excessive fuel dilution leads to sludge and varnish, requiring the oil to be changed more often.

Additive are designed to deplete

Additives are added to base oils to reduce destructive processes and enhance beneficial properties. For example, antioxidant additives help slow the rate of oxidation. Detergency additives help prevent deposits and sludge while cleaning pre-existing deposits. Anti-wear additives are added to some lubricants to form a sacrificial barrier on metal components and help prevent wear.

Since they’re sacrificial in nature, additive depletion is one of the primary reasons motor oil loses its effectiveness and must be changed.

Though all motor oils eventually deteriorate, synthetic oils last longer than conventional oils and deliver improved protection against wear and deposits. They’re formulated with base oils that are more resilient to oxidation and heat, while their additives also typically offer improved performance.

In fact, AMSOIL Signature Series Synthetic Motor Oil performs so well you can go up to 25,000 miles/one year between oil changes (15,000 miles/one year in severe service) if you want, saving money.