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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.

How Engine Sludge Forms. And How To Prevent It.

AMSOIL Signature Series virtually prevented engine sludge on this oil pick-up screen.

Engine Sludge Is Easily Avoidable

Engine sludge.

It’s a back gelatinous substance that wreaks havoc in engines. And long before the engine’s demise, engine sludge can foul engine sensors and interfere with performance. Some mechanics call it the “black death.”

How does motor oil, which is fluid, become a semi-solid paste or gel inside an engine?

Here’s what we’ll cover:

  • How engine sludge forms
  • The effects of engine sludge
  • Synthetic oil helps prevent engine sludge
  • High-quality additives fight engine sludge
  • Severe service invites engine sludge

How engine sludge forms

Engine sludge is the result of a series of chemical reactions.

The lubricant degrades as it is exposed to oxygen and elevated temperatures. The higher the temperature, the more rapid the rate of degradation. In fact, every 18°F (10°C) increase in temperature doubles the rate of oxidation.
Many people still believe any oil is fine as long as you change it often but 95% of the brands out there do not address that inch of protection when you really need it!! We’ve all had issues where the engine is overheating or some situation where adequate lubrication isn’t available. AMSOIL offers 75% more protection when you need it and our diesel oils offer 6X more protection than required by industry testing.

The by-products of this reaction form highly reactive compounds that further degrade the lubricant. Their by-products react with other contaminants, forming organic acids and high-molecular-weight polymeric products. These products further react, forming the insoluble product known more commonly as sludge.

What begins as a thin film of lacquer or varnish deposits on hot or cold metal surfaces and bakes into an expensive mess.

The effects of engine sludge

Sludge can block the oil passages and oil-pump pick-up screen, resulting in oil starvation. Often, the negative effects are cumulative rather than sudden.

Many engines with variable valve timing (VVT) use oil-pressure-operated mechanical devices to change valve timing, duration and lift. Sludge can plug the solenoid screen or oil gallies and impact the operation of VVT mechanisms, eventually leading to a costly repair bill. Sludge reduces efficiency and increases time and money spent on maintenance.

Who doesn’t want a cooler engine? Sludge, even the early stages prevents the engine from dispersing heat efficiently. Why would you risk a Group III “synthetic” which does leave deposits adding to or resulting into an engine which struggles to exhaust heat.

Synthetic oil helps prevent engine sludge

Fortunately, sludge and varnish deposits are something oil manufacturers can control. Using thermally stable synthetic base oils reduces the rate of degradation (oxidation). (Yes – and that is “Real 100%” Synthetics – not the ones they currently call “Fully”..

Anti-oxidant additives help reduce the rate of degradation as well. One of the most widely used is zinc dithiophosphate. Not only is it an excellent oxidation inhibitor, it is an outstanding anti-wear additive as well.

High-quality additives fight engine sludge

We can further address many of the issues occurring after the initial oxidation stage.

Additives, such as detergents and dispersants, are commonly part of motor oil formulation. They help promote the suspension of contaminants within the oil and keep them from agglomerating.

Detergents, which are also alkaline in nature, assist in neutralizing acids generated in the sludge-building process. Anti-oxidant, dispersant and detergent additives are consumed during use.

To achieve maximum life expectancy, use an oil with high concentrations of anti-oxidant, dispersant and detergent additives.

AMSOIL Signature Series Synthetic Motor Oil, for example, has 50 percent more detergents* to help keep oil passages clean and promote oil circulation. It provides 90 percent better protection against sludge**.

Signature Series Synthetic Motor Oil was subjected to the Sequence VG test to measure its ability to prevent sludge. Signature Series produced an oil pick-up tube screen virtually free from sludge. Our unique combination of detergents and high-quality base oils control oxidation and sludge to keep engines clean and efficient.

PDF of the test where AMSOIL has this done (Southwest Research)

AMSOIL Signature Series virtually prevented engine sludge on this oil pick-up screen.

Buy Signature Series

Severe service invites engine sludge

Equipment operating conditions also influence the likelihood of sludge or varnish issues.

Stop-and-go driving, frequent/long-term idling and operation in excessively hot or cold weather can increase the likelihood of sludge and varnish, especially if using more volatile conventional oils. If sludge has already formed, you can use an engine flush to clean sludge from your engine.

Interestingly, most auto manufacturers note in their owner’s manual that operation under any of the above conditions is considered severe service and requires more frequent oil changes.

From a mechanical standpoint, things like adding too much oil to the oil sump, antifreeze contamination, excessive soot loading, excessive oil foaming, poor engine-combustion efficiency, excessive blow-by and emission-control-system issues can all lead to the formation of sludge and varnish.

By practicing good maintenance and using properly formulated, premium synthetic lubricants, like AMSOIL synthetic motor oil, your vehicle won’t succumb to the “black death.”

Taking it a step further which many of our customers do – to make sure your vehicle is always running in peak condition one thing is to have your oil analyzed. I do it not so much to see how the oil is doing but to measure what may be going on in the engine to deplete detergents or to test for any out of typical wear levels, fuel in the crankcase, and to see if the viscosity is still on par.  Oil analysis kits are easy to use especially when you have the dipstick extraction pump.

*vs. AMSOIL OE Motor Oil
**Based on independent testing of AMSOIL Signature Series 5W-30 in the ASTM D6593 engine test for oil screen plugging as required by the API SN PLUS specification.

Don’t Let Extreme Heat Sideline Your Motorcycle

Dyno control

An Oil to Resist Thinning from Extreme Heat and Mechanical Activity

Extreme summer heat combined with slow-moving rally or parade traffic can pose big problems for you and your motorcycle.

As heat intensifies, motor oil loses viscosity and becomes thinner. The oil can become so thin that the engine loses oil pressure, causing the oil-pressure gauge to bottom out. You may hear increased valvetrain and gear noise as parts clatter together. A good rider knows not to ride with no oil pressure, so he or she will shut down the bike and sit alongside the highway (or push the bike) until the engine cools enough to restore oil pressure.

Decreased airflow stresses oil

Air-cooled V-twins get plenty hot on their own, but riding in slow moving traffic makes it worse. Crawling along barely above idle doesn’t generate enough airflow to cool the engine. Add to that the blazing sun reflecting off the asphalt, and it’s a recipe for trouble. In extreme dyno testing designed to create heat, we’ve seen cylinder temperatures in a 2012 Harley-Davidson* Street Bob* as high as 383°F (195°C).

It’s up to the motor oil to protect the engine despite the intense heat; however, oil becomes thinner as it heats up. If it becomes too thin, it can fail to form a lubricant film of enough thickness and strength to prevent metal components from contacting during engine operation and wearing out. Once the lubricant film fails, it falls on the anti-wear additives to prevent wear. They form a sacrificial layer on components to keep them from contacting. But additives are designed to deplete with time and use. Once they wear out, your engine isn’t protected in this scenario.

Heat breaks down oil faster

The rate at which oil oxidizes, or chemically breaks down, doubles for every 18°F (10°C) increase in lubricant temperature. Oxidation occurs when oxygen molecules attack oil molecules and result in a chemical reaction that leads to harmful byproducts, like sludge and varnish. The faster the oil oxidizes, the sooner it wears out and requires changing.

Ride Hard. Run Cool.®

AMSOIL Synthetic V-Twin Motorcycle Oil uses high-quality synthetic base oils that naturally resist thinning due to extreme heat and mechanical activity better than conventional base oils. As a result, it forms a thick, strong lubricating film on engine components despite the intense heat. Although any oil will become thinner in extreme heat, riders who use AMSOIL Synthetic V-Twin Motorcycle Oil won’t see their oil-pressure gauges bottom out, providing the confidence they need to keep riding after others have shut down their bikes and started pushing.

Find AMSOIL Products for My Bike

*All trademarked names and images are the property of their respective owners and may be registered marks in some countries. No affiliation or endorsement claim, express or implied, is made by their use. All products advertised here are developed by AMSOIL for use in the applications shown.

Why Does Motor Oil Turn Black?

Why Does Motor Oil Turn Black?

Motor Oil Turning Black Isn’t an Indicator of Bad Oil

What causes black motor oil? And when your oil darkens does it mean it’s time to change it? Well, there are a couple of factors that can cause the former. Let’s dig in.

Factors causing black motor oil

Heat cycles naturally darken motor oil

During your drive to work in the morning, your engine reaches normal operating temperature (typically 195ºF-220ºF), heating the motor oil. Then the oil cools while your car sits in the parking lot. During lunch, the oil again is exposed to heat during your drive to Walmart for butter and shoe laces. The process repeats on the way home. And the next day. And the next.

That’s what’s meant by “heat cycles.” The continual exposure to periods of high heat naturally darkens motor oil.

Some additives in motor oil are more susceptible to darkening in the presence of heat than others. In addition, normal oxidation can darken oil, too. Oxidation occurs when oxygen molecules interact with oil molecules and cause chemical breakdown, just like how oxygen causes a cut apple to brown or iron to rust. High heat accelerates oxidation.

Soot causes oil to turn black

While heat cycles cause oil to darken, soot causes oil to turn black. Most people associate soot with diesel engines, but gasoline engines can produce soot as well, particularly modern gasoline-direct-injection engines.

Soot is a byproduct of incomplete combustion. Since soot particles are less than one micron in size, they typically don’t cause engine wear. For comparison, a human hair is roughly 70 microns in diameter.


If soot particles agglomerate into larger wear-causing contaminants, the oil filter will catch them. Sometimes people who use bypass filtration systems, which can filter contaminants down to two microns, express surprise that the motor oil is still black. Soot, however, can still elude filtration down to two microns. Any finer filtration and the filter could catch dissolved additives in the motor oil.

Oil Myth: The color of the oil indicates when it’s time for an oil change

It’s common to assume that black motor oil has worn out or become too saturated with contaminants to protect your engine and requires changing. Not necessarily. As we saw, discoloration is a natural byproduct of heat and soot particles, which are too small to wear out your engine.

The only surefire way to determine if the oil has reached the end of its service life is to perform oil analysis. Chemically analyzing an oil sample reveals the condition of the oil, the presence of contaminants, fuel dilution and so on. Several companies offer oil analysis services, including Oil Analyzers INCWe keep the kits here in Sioux Falls

Absent oil analysis, it’s best to follow the oil-change recommendation given in your vehicle owner’s manual or by the motor oil manufacturer. The recommended service intervals for AMSOIL products, for example, are based on thousands of data points spanning years of use.

It’s best to trust the data, not your eye, in this case. Otherwise, changing the oil could amount to throwing away good oil.

Time for an oil change? Find AMSOIL product for your vehicle here.

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.