Is Motorex Fork Oil OK for my Marathon?
Motorex is considered among the very best fork oil for motocross. Very slick stuff. Check out the specs. People talk about Torco, belray and others, but Motorex is great. Pick the weight oil you want and go for it. I only use motorex in my dirtbike.
From another post: Tscheezy recommened that when I buy non-brand specific oil for my Marzocchi Z1 SL that I make sure it is "cartridge rated" otherwise it will swell the seals.
Is Motorex "cartridge rated"? And what does that mean?
Almost every fork made since the late 80s is cartridge style. I don't think you could find a fork oil that is NOT cartridge rated.