We sat down with Mike Marcella, Director of Technology at Maxima Oils to answer some of your oil queries

A lot of times we get questions on why we need to top-up on oils between service intervals, types of oil, oil grades, DiYs, etc? To address this growing curiosity among other motorcycle enthusiasts, we are sharing some useful insights.

Oil consumption and vaporisation

Let’s start by discussing what could possible lead to it and is this a normal occurrence?

What is engine oil Vaporisation?

Vaporisation is when the oil goes from the liquid phase to the gas phase.

What is engine oil Consumption?

Consumption is any loss of oil, which can be caused by vaporisation or can be caused by other factors.

Can the oil formulation contribute to the oil consumption?

From a formulation perspective, vaporisation is driven by base oil and viscosity. Higher quality base oils (synthetics) and higher viscosities are more resistant to vaporisation. We at Motousher sell Maxima Oils that use the highest quality mineral base oils (grp II+) and the highest quality synthetics (grp IV PAO and grp V esters). Additionally, Maxima Racing oils are quite resistant to vaporisation.

To address the issue from a lubricant perspective, one can either use a higher viscosity grade or switch to a fully synthetic oil.

If not the oil what else can contribute to consumption?

Hardware also contributes to consumption in several ways. Excessive operating temperatures can cause even highly stable oils to vaporise, resulting in consumption. Poor seal between the combustion chamber and crankcase can also contribute to consumption, as oil gets into the combustion chamber and then is burnt and lost through the exhaust. Lastly, engine leaks also contribute to consumption.

We also need to factor in weather conditions as a factor i.e. warmer temperatures can impact consumption as well as health of the engine.

Oil Grade

We have heard of people moving up oil grades from say a 10w40 to a 10w50, what are the implications of moving down from a 10w50 to 10w40?(question specific to some of the Triumph Motorcycle models)

In general, we always encourage the user to stay within the recommendations of the Owner’s Manual. In this specific case, both viscosity grades are recommended by Triumph for this model, depending on ambient conditions. Therefore, there is little chance of damage from decreasing the viscosity.

However, additional vibrations are certainly possible and perhaps even likely, depending on how large the viscosity discrepancy is between the 10W-50 and 10W-40. Hardware continues to wear down to a small degree over time. At the moment the hardware has been wearing for some time on the 10W-50, increasing the tolerances between moving parts and becoming more acclimated to the film thickness delivered by a 10W-50. As such, while protection should still be perfectly sufficient using a 10W-40, some vibrations may be expected and the chances of blowby also increase.

Ultimately, it’s up to the customer’s preference. They can try the 10W-40 and if they experience any vibrations or loss of fuel economy due to blowby, then they can always switch back to the 10W-50.

Moving up in viscosity in hot weather is always good but moving down is another question altogether.

On my Triumph Tiger I have been using 10w50 over the past few years, do I need to continue to stay at a 10w50 or can I move down to 10w40?

Moving to a 10W-40 is ok, but vibration and blowby are possible side effects

Are there any advantages of going back to a thinner grade oil

Provided no extra blowby occurs, the thinner oil can allow for improved efficiency, power and slightly reduced operating temperatures

There are forums that talk about how over time gaps between moving parts increase. Will a thinner oil mean an increase in vibrations?

This is a possibility due to the increased clearances between parts created by the thicker oil film of the 10W-50; the larger the viscosity discrepancy between the oils, the higher the chances this will happen

My reason in the first place to move to a 10w50 was taking into consideration the temperature and traffic conditions which meant a lot of heating in stop and go traffic. Is it a good enough reason to still stick to 10w50?

From my perspective, the possible benefits of moving to a 10w-40 do not outweigh the possible detriments; if it were me, I’d stay with the 10w-50

Last question does a 50 or a 40 grade oil have any impact on how much energy the engine has to put to move parts and does it directly impact the heat it has to produce to move those parts?”

To an extent, but it depends on the viscosity discrepancy between the oils and numerous other factors; in general this is true, but all other variables would need to stay constant between the two to see any real world improvements in efficiency or operating temps