I'm just wondering about using Royal Purple 20w50 for the engine on my HD. I was planning on using Amsoil but a friend gave me 4 qts of the RP motorcycle 20w50. I haven't come across any forum comments or topics on Royal Purple so I was curious as to the quality. Thanks for any and all opinions on this.
2008 GMC Sierra 4.8 4x4 Amsoil OE5w30
2006 Honda Accord 4dr Auto Amsoil SS0w20
2010 Harley Streetglide Amsoil MCV20w50
2011 Kawasaki Kx250f Amsoil MCF