Have a friend that would like to use the Castrol motorcycle oil. It's easy to obtain at Kragen and meets a higher standard than the Mobil 1 according to the specs on the bottles. Anyone know if it's a true synthetic and if is as good as Mobil1? Castrol claims the automotive oil has 8 times the protection as Mobil 1. I still use Redline in all my motors and unable to convince the person wanting to use Castrol. Grey any knowledge????