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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.

Z-ROD® Keeps Classic Vehicles Street-Ready

Vintage Car and Cam Wear Problems Solved – Zinc Fortified Motor Oils

After this long Sioux Falls winter, making the transition from storage to the street can be an anxious time for classic car owners. Even after extensive preparations, doubts may linger whether a prized vehicle has been effectively protected during a period of inactivity. Many owners now look to modern technology to keep vintage hot rods and muscle cars performing at a high level on the street and fully protected during storage.

Protecting engines designed decades ago- and engines modified for increased performance- can be challenging. From flat-tappet cams and splash-lubricated components to the toll of periodic storage, unique issues must be addressed.

Amsoil Z-Rod high Zinc oil

Flat-Tappet Cams and ZDDP

The design of flat-tappet cams makes them especially vulnerable to wear. As the name indicates, the tappet- or lifter – is flat. During operation the surface of the cam lobe slides rapidly over the surface of the tappet, producing high friction and temperatures. The camshaft and lifters are responsible for triggering the precisely tuned movements of the valve train. Here, the use of anti-wear additives becomes crucial.

Stop Cam Wear – No Aftermarket Oil Additives Needed

Zinc dialkyldithiophosphate (ZDDP) is a commonly used motor oil additive that provides anti-wear protection and minimizes lubricant breakdown. ZDDP also exhibits mild extreme-pressure protection. As temperatures in an engine rise, ZDDP decomposes, and the resulting chemistry protects critical metal surfaces.

Without the protective film barrier provided by ZDDP, the cams and lifters wear from the force of operation, negatively affecting cam and valve operation. Because most V-8 engines of the muscle car era came standard with flat-tappet cams, the problem is prevalent to classic-car and hot rod owners.

In these applications, modern oils, such as AMSOIL synthetic motor oils, are capable of providing adequate wear protection after the engine has been broken in. But due to variables like severity of service and level of modification, AMSOIL primarily recommends high-ZDDP oils in these applications, such as Z-ROD® Synthetic Motor Oil. When breaking in a rebuilt or high-performance engine, AMSOIL recommends AMSOIL Break-In Oil, which contains high levels of ZDDP for added protection.

Rust and Corrosion

Moisture can be as devastating an engine contaminant as dirt or sludge. Vehicles subjected to long-term storage are especially vulnerable to humidity-driven rust and corrosion. AMSOIL Z-ROD® Synthetic Motor Oil is formulated with a unique blend of rust and corrosion inhibitors to ensure maximum protection during storage.

AMSOIL Z-ROD® Synthetic Motor Oil (ZRTZRF)

  • 10W-30 and 20W-50
  • Protects flat-tappet cams
  • Long-term rust and corrosion protection

AMSOIL Break-In Oil (BRK) SAE 30

  • Quickly seats rings
  • Protects vital parts from wear
  • Increased film strength

Other AMSOIL Motor Oils containing substantial Zinc levels for Gas & Diesel engines

Call about any of these oils by calling us at 800-579-0580

Or visiting the Sioux Falls store at 47073 98th St. Also find AMSOIL at Stan Houston’s on 12th St!!