Originally Posted by Bill G

Hear are some answers from Harley, look at question #5 for the MoCo answer to your qustion.

Ride Safe,
Bill G


Ten Questions and Answers About Motorcycle Oil For Your Harley-Davidson



The Following Information was provide by
Harley- Davidson Service, 3rd Floor.


1. Why should I use Harley-Davidson Motorcycle oil?

This is the only available motorcycle oil specially developed for Harley-Davidson motorcycle engines. It is also the only available oil tested for two years by our engineering staff on engine dynamometer stands in Milwaukee and motorcycle track tests at Talladega. And in other tests, Harley-Davidson has found it to be superior to other oils.

2. Can I use aviation oils in my Harley-Davidson?

We do not recommend this, because these oils do not contain an important additive that provides good wear protection of the Harley-Davidson engine.

3. What viscosity grade should I use in my Harley-Davidson?

The recommended viscosity grade for use in all temperatures is SAE 20W50 Harley-Davidson Oil. The SAE 50 grade is satisfactory in ambient temperatures of 60 deg to 90 deg F, and the SAE 60 grade is appropriate for ambient temperatures above 80 deg to over 100 deg F.




4. At what temperature will Harley-Davidson Motorcycle Oil
break down?

This oil has been designed for use at temperatures up to 300 deg F for extended periods with no significant breakdown.

5. What oil temperature is best for my Harley-Davidson?

A good oil operating temperature range is 200 deg to 240 deg F. Water condensation and acids tend to build up in the oil if the temperature is consistently below 180 deg F, and oil thickness can become marginal at temperatures above 300 deg F.



6. Does Harley-Davidson Motorcycle Oil do anything besides
lubricate engine parts?

Yes. Besides lubricating engine parts and preventing wear, it protects the engine from rust and corrosion, keeps the inside of the engine clean, cools engine parts and "seals in" combustion pressures, prevents foaming, permits easy starting and quick oil circulation, and reduces friction and power loss.

7. Is it true that oil never wears out?

No. All motor oils wear out. During normal use, the oil molecules undergo a chemical reaction with oxygen and begin to break down; additives in the oil become depleted; and contaminants like water, gasoline, soot and dust get mixed in with the oil. Therefore, your motorcycle oil needs to be changed at the interval recommended by Harley-Davidson.

8. Can I go longer between oil changes if I put in a new oil
filter?

No. The filter keeps the oil free of solid matter, but it doesn't remove water, gasoline or acids. Also, it can't pinch-hit for additives that become used up. Follow Harley-Davidson's recommended intervals for oil and oil filter changes, and don't expect a new filter to extend the life of the oil.

9. Is it okay to mix Harley-Davidson Motorcycle Oil with a
different brand?

Harley-Davidson Motorcycle oil is compatible with other petroleum oils. However, mixing with another oil will reduce the superior engine protection of Harley-Davidson oil, so this should be done only when absolutely necessary.

10. Does it help to put in a can of additive with each oil
change?

No. Just as you wouldn't add sugar to a bottle of soda, you shouldn't use additives with Harley-Davidson Motorcycle oil. It already contains the right additives in the correct amounts to last between recommended oil changes. More additives won't help. In Fact, they might upset the oil chemistry and create problems you wouldn't ordinarily have. Use Harley-Davidson Motorcycle Oil and forget the extra can of additive. It's money down the drain.

Originally Posted by UALCapt

I have.

Originally Posted by bobros

This artilce sounds like it was done by the Marketing Department moreso than the Engineering Department.

Originally Posted by Bill G

I would say all the questions and answers are valid except for Harleys standard answer on question #1 and some question #4 validity about HD-360 oils going to or being tested to 300 degrees. We all know there are other brand oils other than Harley oils that work as well and even better. The rest of the answers are basically right on the money no matter who wrote it...

Ride Safe,
Bill G

Originally Posted by iclick

Not #9 that claims that adding another brand of oil to the mix will reduce the "superior" qualities of the HD product. This is false and they can't show evidence for that claim. Other than this one the other claims are cleverly worded to have a double meaning if legally challenged.

Originally Posted by iclick

So if I have Syn3 in my crankcase and need to add a quart of Mobil 1 that I'm reducing the protection? Baloney. They are saying here that every other oil is inferior to HD oil and they cannot and will not provide evidence to support this claim. Further, no independent oil test that I've ever seen bears this out.

Originally Posted by Bill G

I will not argue with you about #9 and HD or the MoCo being right or wrong about it but it is not a good practice in general to mix oils even though it can be done.