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Synthetic Oils
Almost always better than petroleum based

By: James R. Davis

In almost all cases the use of synthetic oil (at least now) is better in your motorcycle than straight petroleum based oil. But not in all cases. Oil additives with Teflon® in them, for example, don't make any sense to me.

I guess some people might not understand that a good part of petroleum based oils are synthetics anyway (virtually all the additives). Thus, we already have some experience with synthetic lubricating fluids in our engines.

The principal drawback to the synthetics is that they are more expensive than straight petroleum based oils. But in exchange for that higher price you usually get your money's worth. Longer life before they have to be changed, more consistent performance regardless of temperature or engine RPM, better lubrication (more slippery), as well as all the functions of better oils with their additives.

But your oil does more than help pieces of metal slide/roll easier. It has the job of loosening and keeping in suspension sludge and varnish. It has the job of absorbing moisture to inhibit rust and to diminish corrosion. It has to have sufficient variability in viscosity to continue to do its job regardless of temperature changes. It has to be able to withstand shear forces as well as heat and pressure. And, not incidentally, they must not destroy seals while they work.

Generally, synthetics are made today that do all of this, and more, as well as or better than petroleum based oils.

Some synthetics were not as well designed in the past as they are today. Mobil-1, for example, used to eat seals, for example, but it no longer does.

Manufacturers recommend against using synthetics during your engine break-in period. This, because these oils are too slippery and normal break-in wear would not take place as quickly as without them.

Many of those manufacturers used to advise against mixing synthetics with regular oils until they found that they were denying themselves of much of their markets by doing so. Now these synthetics are made so that they can be mixed without any trouble (But I would recommend NOT doing so in any event.)

It is simply not very smart to put some brands of synthetic additives into a motorcycle - such as 'Slick 50'. First, because you run a wet clutch and this kind of synthetic could render your clutch quite inefficient and possibly useless, depending on how much of that product you use. (If not, there may well come a time when you elect to no longer use it and you may well find that your clutch has to be rebuilt just to get rid of what was in there.)

Second, because their claim of bonding Teflon® to metal cannot be true, and if the manufacturers of that product need to rely on false claims to sell their products, what else might they be saying that you are relying on?

Third, because Teflon® is a SOLID! Your oil filter is designed to get rid of solids. Teflon® greatly increases in size with high temperatures - so even if the microscopic sized particles will travel thru your filter to start with, there will come a time when you actually ride your bike and it warms up. Then there are all the other oil flow surfaces and oil passageways that will get smaller as a result of being coated with Teflon®. In any event, the next Tip will discuss additives containing Teflon® in detail.

In summary, I agree that virtually all the synthetic oils are better for your motorcycle than are regular petroleum based oils. They are more expensive, but probably worth the added cost. Your shifting will be easier, you can go longer between oil changes, and you should experience slightly less engine wear by using them.

[Not incidentally, you can expect about a 1% increase in engine power if you use synthetics.]

Teflon® is a registered trademark of DuPont.

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(James R. Davis is a recognized expert witness in the fields of Motorcycle Safety/Dynamics.)

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