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Why You Should Be Wary About Using Break In Oil in Powersports Equipment

Why You Should Be Wary About Using Break In Oil in Powersports Equipment

Marco Navarro asks on our Facebook page about break in oil, with attention paid to powersports engines.  (Break in oil importance, drain interval on it, and applications. To include motorcycles and ATVs since life of engine is shorter and rebuilding occurs more often.)
Thanks for the question, Marco.

Let’s get to it.

Maintaining an engine is a constant fight against wear. Over time, wear not only results in expensive damage, it reduces compression, robbing your engine of power.

That’s why it can be tough to accept that “controlled wear” during a new or rebuilt engine’s break in period is critical to maximizing its power and longevity.

Take a seat

One of the primary reasons to break in an engine is to seat the piston rings, and that means allowing the rings and piston skirt to carefully wear down the peaks (called asperities) on the cylinder wall.

The images show what we mean.

Although a new or freshly honed cylinder appears smooth to the naked eye, it contains microscopic peaks and valleys. If the valleys are too deep, they collect excess oil, which burns during combustion and leads to oil consumption.

The sharp peaks, meanwhile, provide insufficient area to allow the rings to seat tightly. That means highly pressurized combustion gases can blow past the rings and into the crankcase, contaminating the oil and taking potential horsepower with it.

Breaking in the engine wears the cylinder-wall asperities, providing increased surface area for the rings to seat tightly. The result is maximum compression (i.e. power) and minimum oil consumption.

Getting the shaft

That brings us to the other primary reason to break-in an engine: to season, or harden, the flat-tappet cam. Flat-tappet cams can wear out faster than their roller-cam cousins, especially in engines modified with high-tension valve springs.

And cam wear is bad. Really bad. Worn lobes or tappets affect valve lift and duration, which reduces engine power and efficiency. In extreme cases, increased pressure can remove material from the lobes and deposit it in the oil, where it circulates through the engine and causes damage. Break-in helps harden the metal so it’s more resilient to wear.

That raises a critical question: How do we simultaneously allow controlled wear to the cylinder wall/piston rings while protecting the cam against wear? Those two tasks seem mutually exclusive.

In a word, oil

The solution is to use a properly formulated break in oil that allows controlled wear at the cylinder wall/piston interface, but that also protects the cam lobes and tappets from wear.

How do we accomplish this black magic?

Most break in oils, including AMSOIL Break-In Oil, use conventional base oils. Compared to their higher-quality synthetic counterparts, conventional base oils result in a thinner, less durable protective oil film on engine parts. The thinner fluid film allows controlled wear at the cylinder wall/ring interface.

But what about the cam? Won’t it wear, too?

ZDDP

That’s where anti-wear additives come into play. ZDDP anti-wear additives are heat-activated, meaning they provide wear protection in areas of increased friction. In this case, it’s at the cam lobe/tappet interface. The additives form a sacrificial layer on the surface of parts, which absorbs contact and helps prevent cam and tappet wear.

As a rule of thumb, a good break in oil should be formulated with at least 1,000 ppm ZDDP. At AMSOIL, we take it a few steps further; our Break-In Oil contains 2,200 ppm zinc and 2,000 ppm phosphorus.

How long does break in require?

Another rule of thumb states you should season a flat-tappet cam by running the engine above 2,500 rpm for 15 minutes.

As for seating the rings, our testing has shown it can take as little as seven dyno passes. That time varies depending on the engine, ring tension, cylinder hone and other factors.

If you don’t have access to a dyno, follow the engine builder’s or manufacturer’s recommendations. If none are provided, consult the recommendations on the break in oil label. In general, run the engine under light-to-moderate loads for about 500 miles. Again, that duration is a rule of thumb, but break in shouldn’t exceed 1,000 miles. Then, drain the break-in oil, install the synthetic oil of your choice and commence driving.

An engine dyno provides the best method of determining exactly when the rings are seated. You’ll notice a boost in horsepower as the rings seat. Eventually, horsepower will stabilize once the rings are seated.

Check out 5 Ways to Boost Horsepower for Under $500

You can also perform a leak-down test. Another, albeit more time-consuming, method is to remove the exhaust headers and check for oil residue in the exhaust ports. Presence of oil shows the engine burning oil, meaning the rings aren’t completely seated. Once the oil residue is gone, the rings are seated.

What about powersports engines?

Ask yourself a few questions about your motorcycle, ATV or other powersports application before using a break in oil:

  1. Does it have a wet clutch? If so, the break in oil may not be formulated for wet-clutch compatibility, leading to reduced performance.
  2. Does it use a shared sump with the transmission? Many motorcycles use one oil to lubricate the engine, transmission and primary chaincase. The churning action of transmission gears, especially in high-rpm applications, can tear apart – or shear – the oil if it’s not formulated to handle the stress. Using a break in oil not designed to handle high-shear applications can lead to damage.
  3. Does it have a dry sump? Some motorcycles store motor oil in a tank separate from the engine. Residual break in oil can collect in the system following the break in period and contaminate the service-fill oil. In this case, run the engine long enough to circulate the oil throughout the system and change it a second time to ensure the break in oil is completely removed.

Given the above challenges, we recommend breaking in a rebuilt powersports engine using the motor oil you’ve always used. Run it according to the original equipment manufacturer’s (OEM) new-engine recommendation, then change the oil. In short, treat it like a new engine from the factory.

For new engines, just follow the OEM guidelines. Typically they recommend a shorter interval for the first oil change to remove wear particles and contaminants from the factory. Then, change to the AMSOIL synthetic motor oil that’s recommended for your application and commence riding.

New 20W-40 for Victory & Indian Motorcycles

A premium oil designed for those who demand the absolute best lubrication for their motorcycles. AMSOIL 20W-40

AMSOIL 20W-40 V-Twin Motorcycle oil for Victory & Indian

New AMSOIL 20W-40 Synthetic V-Twin Motorcycle Oil (MVI) is formulated to provide premium protection for Victory and model-year 2013 and newer Indian motorcycles. It is the only full-synthetic 20W-40 motorcycle oil on the market, presenting riders a premium alternative to Indian- and Victory-branded semi-synthetic oils. Indian and Victory motorcycles incorporate a shared sump, and AMSOIL 20W-40 is formulated to provide outstanding protection for engines and transmissions. It is absolutely shear stable, keeping motorcycles well-protected even in extreme heat conditions.

 

AMSOIL 20W-40 Synthetic V-Twin Motorcycle Oil provides Indian and Victory riders with the confidence and security that comes with receiving maximum protection and performance for their bikes. It presents a premium alternative to higher-priced manufacturer-branded semi-synthetic oils.

Expect AMSOIL to always outperform. Seat of the pants tests too!

Expect AMSOIL to always outperform. Seat of the pants tests too!

Reduces Friction, Heat and Wear
AMSOIL 20W-40 Synthetic V-Twin Motorcycle Oil is engineered to protect critical components in high-heat conditions. It exceeds the standard for high-temperature film strength to deliver excellent wear protection (see graph) and contains a heavy treatment of anti-wear additives to reduce wear regardless of operating conditions. AMSOIL 20W-40 is thermally (heat) stable and contains maximum levels of oxidation-inhibitor additives. It is extremely resistant to breakdown and is engineered to prevent damaging sludge and carbon deposits for superior engine cleanliness.

Provides Anti-Wear Protection for Gears and Chains
AMSOIL 20W-40 Synthetic V-Twin Motorcycle Oil is shear stable and resists thinning from mechanical activity. It performs like a gear lube without the negative effects of extreme-pressure additives, such as poor wet-clutch performance.

Delivers Superior Rust Protection
Motorcycles are prone to rust from storage, humidity and short drives. Rust can cause major damage, such as uncontrolled wear, compression loss and blow-by. Good rust protection, however, comes by design and is not natural to motor oils. Unlike many motorcycle oils, AMSOIL 20W-40 Synthetic V-Twin Motorcycle Oil contains special anti-rust agents, providing outstanding protection against rust and corrosion.

Catalytic-Converter Compatible
AMSOIL 20W-40 Synthetic V-Twin Motorcycle Oil meets the requirements for emission-system protection and is designed for use in motorcycles with catalytic converters.

Provides Excellent Wet-Clutch Performance
AMSOIL 20W-40 Synthetic V-Twin Motorcycle Oil delivers the confidence of quiet, smooth shifting and positive clutch engagement. It controls heat and helps prevent slippage and glazing, while its high TBN helps improve clutch life by resisting the acids that can degrade clutch material.

APPLICATIONS
AMSOIL 20W-40 Synthetic V-Twin Motorcycle Oil is recommended for air- or liquid-cooled Indian, Victory and other four-stroke motorcycles calling for a 20W-40 motor oil. It meets API SM, JASO MA and API GL-1 specifications, providing outstanding protection for engines and transmissions.

COMPATIBILITY
AMSOIL 20W-40 Synthetic V-Twin Motorcycle Oil is compatible with other conventional and synthetic motor oils; however, mixing oils may shorten the oil’s life expectancy and reduce its performance benefits. AMSOIL does not support extended drain intervals where oils have been mixed. Aftermarket oil additives are not recommended for use with AMSOIL Synthetic V-Twin Motorcycle Oil.

SERVICE LIFE
For on-road use in engines and transmissions, AMSOIL 20W-40 Synthetic V-Twin Motorcycle Oil and AMSOIL Ea® Motorcycle Oil Filters are capable of providing premium protection for up to 2X the motorcycle manufacturer-recommended change interval or one year, whichever comes first. Change other brand oil filters at standard intervals.

For off-road use in engines and transmissions, change AMSOIL 20W-40 Synthetic V-Twin Motorcycle Oil at the standard motorcycle manufacturer-recommended change interval.

For racing or in engines modified from the original factory design, no change interval recommendation is made; oil changes are at the owner’s discretion.

WARRANTY SECURE™
AMSOIL 20W-40 Synthetic V-Twin Motorcycle Oil is Warranty Secure, keeping your factory warranty intact. AMSOIL 20W-40 Synthetic V-Twin Motorcycle Oil is a high-performance replacement for vehicle manufacturer-branded products and is also backed by the AMSOIL Limited Warranty. For details, visit www.amsoil.com/warrantysecure.