Sport Rider test motorcycle oils!

[Gary Mintz]

Huhwhye & IslaVistaMan

That may have been true 10 years ago but not now. As IslaVistaMan noted.

 

[Jim 5]

I'll second the rotella t 15w-40 and

M1 15w-50 is said to be an excellent bike oil on most of the motorcycle boards I frequent.

I would stay away from the 5w-40 rotella for a shared sump vehicle. There's no science to this other than my knowledge that gears in shared sump bikes shear oil relatively quickly, and my understanding is that a 15w-40 should be more shear resistant than a 5w-40.

 

[Blake Sobiloff]

Assuming that the USPS hasn't lost my sample, Butler should be sending me the results of my 3,925-mile run on Rotella T 5W-40 in my KLR650 any day now. We'll see how well it held its viscosity.

 

[DNS]

"I would stay away from the 5w-40 rotella for a shared sump vehicle. There's no science to this other than my knowledge that gears in shared sump bikes shear oil relatively quickly, and my understanding is that a 15w-40 should be more shear resistant than a 5w-40."

That would be true if the base oils were the same. However, the Shell 5W40 uses a group III base ("synthetic") that needs little viscosity improver. The 15W40 uses a more conventional base oil. I suspect that in this case, the 5W40 is the more shear stable of the two.