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What is the best weight oil to use in the primary?
I run the HD primary oil after draining the syn 3 that came in the bike and I like the hookup on the clutch better with that oil. Otherwise it's 10/30 or 10/40
I use ATF due to the best compatibility with clutch discs. anything will work though. lubrication and cooling of the clutch housing is job of the fluid and most any will do that.
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Everyones opinion is different. I like the HD primary oil in there, I think it gives a bit more lubrication to the chain and sprockets myself. Some clutch packs recommend the atf for their chutches. Depends on what you're running for disks
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