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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.

AMSOIL vs. Mobil 1: How We Perform

AMSOIL vs. Mobil 1: How We Perform

AMSOIL & Mobil 1 – Compared

Most lists of top-10 performance mods include a turbocharger, supercharger, nitrous oxide or updated engine tune. Increasing the engine’s oxygen intake also increases fuel, which boosts power.

“If you love Mobil 1 you should  use Dollar General motor oil. It’s real good too” lol…

While all that extra power is great, it puts additional demands on your engine oil.

(See our 5 Ways to Boost Horsepower for Under $500.)

Horsepower riding on a sheet of paper

Your main bearings – and, for that matter, the time, money and effort invested in your vehicle – rely on an oil film that’s thinner than a sheet of paper. Adding horsepower increases rpm and engine stress, placing even more stress on the oil. Many enthusiasts make compensatory upgrades to the crank, pistons, cam, etc. to handle the additional pressure.

The shear importance of oil 

In this scenario, upgrading the motor oil is often overlooked. But it’s an important consideration since engine upgrades can increase shearing forces, which result in viscosity loss. And viscosity is the most important property of oil.

Check out this post for details: What Does Viscosity Mean (and How Does it Affect Your Engine)?

Shear results when one layer of fluid moves in a direction different from another layer of the same fluid.

Shear (often called mechanical shear) occurs when one layer of oil moves in the opposite direction of another layer of the same oil. A great example occurs between the piston and cylinder wall. These two oil films move in opposite directions under intense heat and pressure. This is why high-horsepower, high-rpm engines create increased possibility for viscosity loss due to shear.

This scenario can shear, or tear apart, the molecules of viscosity-improver additives, which are used to extend the viscosity range of the base oil. The application and type of base oil determine the type of viscosity improver. Some viscosity improvers resist shear better than others. And some synthetic oils don’t need viscosity improvers at all due to their ability to withstand shear.

A breakdown in protection

If the oil loses viscosity due to shear, it can fail to provide the required level of wear protection. Think of the force transferred through the piston, rod and crank to the thin oil film protecting the bearing. There’s not much room for error.

AMSOIL uses naturally shear-resistant base oils combined with top-tier, shear-stable viscosity improvers. AMSOIL synthetic motor oil withstands extreme heat and shearing forces, exceeding industry standards and outperforming competing brands. In fact, it fights viscosity breakdown 46 percent* better than Mobil 1. It stands up to the devastating effects of high-horsepower, modern engines for maximum protection.

 

FIND AMSOIL FOR MY VEHICLE

*Based upon independent testing of Mobil 1 Annual Protection Full Synthetic and AMSOIL Signature Series 5W-30 in the Kurt Orbahn test, oils purchased on 05/03/18.