05-01-2016, 12:18 AM
In most of my other bikes I used either Rotella T6 5w40 Synthetic or Valvoline Extreme Blue 5w40 Synthetic. They were all large displacement metric v-twins which ran and shifted well with the diesel oil. Diesel oils have good shear resistance when used with straight-cut gearing. However, they generally have higher ash, phosphorous and sulfur content and can possibly coke-up valve stems on bikes prone to such issues (like early 1700 Road Stars). Also, if you check, you will find that Rotella T6 is technically considered "synthetic" by definition, but is, in fact, mostly highly-refined dino oil.
I tried Motorcycle specific 10w40 synthetic in my CB and it didn't seem to like it as much and there was more bottom end noise. I know that it is harder to find in some places, but lately I have only been using 10w30 metric 4-stroke motorcycle-specific synthetic. You can almost always find someone who deals in Amsoil who can ship this to you.
I tried Motorcycle specific 10w40 synthetic in my CB and it didn't seem to like it as much and there was more bottom end noise. I know that it is harder to find in some places, but lately I have only been using 10w30 metric 4-stroke motorcycle-specific synthetic. You can almost always find someone who deals in Amsoil who can ship this to you.