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I'm one that likes to play around and find the oils that "give ME the warm fuzzies"
SOOOOOOOOOO
Engine gets a 50/50 mix of Amsoil 60 Valvoline Racing 50 dino and a bottle of STP oil treatment
Primary gets 50/50 mix of Amsoil 60 and Royal Purple 20/50 Max Cycle
Trans gets a 50/50 mix of Redline HSP and Formula +
Then once a month a little fuel injection cleaner in the tank
Why? Because that's the mixture that I came up with that I liked the best.... for ME
Here is the best approach I have found to the fluids.
M1 20w50 V-twin in the engine
HD Formula + in the primary
Redline Heavy Shock Proof in the transmission
Exactly what I do.
But your question was on the good and bad of doing it one way or the other. My friend runs three holes the same with the thought of being on the road he only has to carry one jug of oil in case of emergency. Funny because after thousands of touring miles with this guy I have only seen him once add any fluids to his bike (they are always new).
My thought is that a tranny needs gear oil, it's what it is made for. Plus in my experience it runs quieter and shifts better. Especially with the Redline.
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