It's a lot of reading, but this is the last word on OIL for Harley Davidson Motorcycles. If you don't want to read the whole report, skip to the conclusions on the last couple pages.
Oil and the Modern Harley-Davidson® Motorcycle
Lee C. Bussy
September 9, 2005
Here is the link to the report pdf file.
Thanks to Lee C. Bussy for his hard work in compiling this report.:hii
Thanks Bigfoot, the report was really good. I posted a question on this forum asking whats wrong with HD oil and like the author stated you get a lot of answers.
Being a Machine Repair all my life I have had to stay in the know of oils in my job and have worked with factory reps and Engs picking out the right and the best oil for the job on hundreds of machines in my time.
Just like the the report stated some of our Engs at work were taken in by that ball bearing test years ago. They thought that someone had reinvented the wheel.
After a lot of money was spent on SYN oils and studied for several years the SYN oils were found to pay off mostly on gearboxes that were in real high heat areas..300* and up. They did last longer, and we keep it in those.
But after the dust settled we returned to what the Manufactor guidelines stated to use in 95% of the jobs, usually gear lube and followed the oil changing times.
Some of the problems we had with SYN was high oil usage caused by seals leaking and not being repaired, the SYN could not be blamed for that, so another reason to go back to gear lube.
You know GM had to save money. This way they saved money on the Oil and repair time...
This was the best report on HD oils that I have found and its a good one.
thanks....
Maybe HD oils are pretty good after all.....