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Don’t Let Extreme Heat Sideline Your Motorcycle

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.

How Oil Consumption Affects Your Turbo Diesel’s Exhaust System

How Oil Consumption Affects Your Turbo Diesel’s Exhaust System

Ever wonder why engines have that long wiry thing with the small plastic handle? A.K.A. the dipstick?

“Come on, Mark, it’s for measuring proper engine oil volume,” you say.

Sure, but here’s the million-dollar question: How often should you pull the dipstick and check your oil level?

Survey the masses and you’ll find that most people only touch the dipstick after they change oil to verify the oil level. Shame on you, masses. Don’t you care about your engine? Continue reading to find out why checking oil frequently is important to protecting your engine.

All engines burn oil

Yes, they do, whether you realize it or not. It’s a natural function of lubricating the piston ring/cylinder liner interface. The rings must seal against the liner for the engine to build compression. Compression builds the horsepower we all love so much. Without that oil film, we’d turn the key, back the truck out of the garage and – BANG! – there goes your engine. Some of the oil film, however, burns with every piston stroke.

Ask yourself again: why do engine’s have a dipstick?

Is it really just to verify the proper oil level after an oil change? Or should we be checking oil more frequently as part of our daily driving routine?

Now that we know all engines burn some oil, we should ask ourselves how long it has been since we lasted checked oil. Pop the hood and pull the dipstick to ensure the engine oil level resides in the safe area on the dipstick. Top-off as needed lest you become that unfortunate person who spills coffee on himself when the engine goes BANG while backing out of the garage.

So, where is the oil going?

Maybe you’re wondering what happens to the oil that burns in the combustion chamber.

If you own a diesel pickup built in or after 2007, listen up.

The oil burns and is pushed into the exhaust stream, just like the byproducts of burned diesel fuel.

All 2007-and-newer trucks are equipped with a diesel particulate filter (DPF). If your truck was built in or after 2010, it has a selective catalytic reduction (SCR) system. These two devices manage the byproducts of diesel combustion and reduce emissions.

How does a DPF work?

The DPF collects and separates the partially burned byproducts of diesel fuel, similar to how an air filter separates and removes airborne dirt particles from the air. These particles collect in the filter until they begin to restrict airflow. At that time the engine reacts and dumps fuel into the exhaust stream to raise the exhaust-gas temperature and help burn the soot byproducts. The system effectively reduces emissions and is built into nearly every diesel application these days.

Example of a diesel particulate filter.

What happens to the burned engine oil as it enters the exhaust stream?

Unfortunately the burned byproducts of engine oil lodge in the DPF and remain there forever. Alternatively, you can remove the DPF for cleaning or replacement.

The problem with oil consumption in diesels is that it can prematurely plug the DPF, rendering it useless.

So, let’s reiterate: all engines burn oil, which can plug the DPF.

That’s the reality with today’s technology. That’s another reason why it’s important to pull the dipstick on a regular basis and track your oil consumption.

The other unfortunate part is that you can do very little to affect how much oil your engine burns. Design tolerances and engine manufacturing affect oil consumption the most.

Your choice of engine oil can make a difference, though

All is not lost, however. Some engine oils offer better protection against oil consumption than others. AMSOIL synthetic diesel oils, for example, have low rates of volatility (burn-off), reducing oil consumption. AMSOIL Signature Series Max-Duty Synthetic Diesel Oil provides up to 76 percent less oil consumption than required by the API CK-4 standard in the Caterpillar-1N oil consumption test. AMSOIL synthetic diesel oils are formulated to protect not only your engine but your exhaust after-treatment system.

So, if you are a diesel burner like myself, your choice of engine oil is important. Choose AMSOIL synthetic diesel oil and start protecting your exhaust system.

At the very least, check your oil on a regular basis to ensure the appropriate level.

FIND AMSOIL SYNTHETIC DIESEL OIL FOR YOUR TRUCK