Diesel rating?

[RMC_SS_LDO]

OK, stoopid check. I remember from somewhere that the oil used in a bike (TC88) is supposed to be rated for diesel applications.

Why?
What is the difference?
What code or whatever indicates a particular jug of oil is rated for diesel.
Thanks in advance...

Now back to the regular endless debates over the best oil on the planet....


Later,

Allen

[The_Snowman]

Originally Posted by rmc_ss

OK, stoopid check. I remember from somewhere that the oil used in a bike (TC88) is supposed to be rated for diesel applications.
Why?
What is the difference?
What code or whatever indicates a particular jug of oil is rated for diesel.
Thanks in advance...
Now back to the regular endless debates over the best oil on the planet....
Later,
Allen

This page gives reasons why you can run a diesel rated oil in a motorcycle; I've not heard that it is neccessary to be rated as such before you can use it in a motorcycle however......
http://www.rotella.com/qa/answerresult.php?rowid=81
This gives the current ratings for oil
http://api-ep.api.org/filelibrary/Guidechart2002.pdf

[george douglas]

Originally Posted by rmc_ss

OK, stoopid check. I remember from somewhere that the oil used in a bike (TC88) is supposed to be rated for diesel applications.

Why?
What is the difference?
What code or whatever indicates a particular jug of oil is rated for diesel.
Thanks in advance...

Now back to the regular endless debates over the best oil on the planet....


Later,

Allen

The short answer is that it might be hype from harley to make sure you only use their oil. Since most people are not familiar with the diesel ratings and such, they might be inclined to make sure that they only use the OEM oil from Harley. Harley spec's a CD rated diesel oil that is obsolete, but the newer ratings are backward compatable and can be used. If you look at the API ratings on the bottle you will see SL,CF for example. The SL is for gas engines and the CF is for diesel engines. At any rate most ooil are dual qualified and you would be hard pressed to find an oil with only a gas spec and not the diesel spec.

[engine23]

Originally Posted by george douglas

The short answer is that it might be hype from harley to make sure you only use their oil. Since most people are not familiar with the diesel ratings and such, they might be inclined to make sure that they only use the OEM oil from Harley. Harley spec's a CD rated diesel oil that is obsolete, but the newer ratings are backward compatable and can be used. If you look at the API ratings on the bottle you will see SL,CF for example. The SL is for gas engines and the CF is for diesel engines. At any rate most ooil are dual qualified and you would be hard pressed to find an oil with only a gas spec and not the diesel spec.

Why do big diesel engines have their oil sent off to a lab to be checked instead of changing at a regular interval like a car? If its the same oil and it runs well in a truck for 10,000 miles why cant it do the same in a car or bike?

[george douglas]

Originally Posted by engine23

Why do big diesel engines have their oil sent off to a lab to be checked instead of changing at a regular interval like a car? If its the same oil and it runs well in a truck for 10,000 miles why cant it do the same in a car or bike?

The automotive oil and heavy duty diesel oil is not the same. I may have confused you earlier when I said that all gas oils also have a diesel spec, but this generally is for light duty diesel engines in a pickup or car.

Oil in a car or bike can be run much longer than most people feel comfortable with if the oil is designed for longer service life. In a big class 8 truck engines the oil isn't stressed as bad as in a small car engine. One of the reasons is due to the large sump capacity that allows the oil to run cooler. I have several truckers over the years run the Amsoil at 100,000 mile oil change intervals for example and use oil analysis. Another reason that some truckers choose to go longer on oil changes is the cost and downtime of an oil change. Keep in mind that you are talking around 40 quarts per engine. In my motorhome I have a Detroit diesel in it and I change filters once a year and send oil off to a lab. My engine only holds 25 quarts, but it is still a lot of oil. In a diesel they also have to watch that the percentage of soot doesn't get high enough to cause wear.

[honus402]

M/C and Diesel oils have more zinc and phos and less prone to shearing down a few grades. 15W-40 Delo, Delvac and Rotella are great for most scoots.

[george douglas]

Originally Posted by honus402

M/C and Diesel oils have more zinc and phos and less prone to shearing down a few grades. 15W-40 Delo, Delvac and Rotella are great for most scoots.

Harleys Syn3 shears down to a 40 weight fairly soon in service according to tests and oil analysis that I have done. Maybe they should start pushing diesel oils more.

[BlackDevil96]

I used the Rotella dino oil in my bike, and it was ok. Stuck in traffic last week cooking engine and bike ended up smoking some out the exhaust. I am switching to synthetic this weekend due to its higher flash point.