Changing the oil/primary on a bud's 2006 1200c. I've read about the oil capacity issues and so on but was wondering about primary fluid? I use Amsoil 20w50 in my 2010 Dyna but have read on here about using actual gear oil in the primary?
Which should I use. I don't want to turn this into a "oil" thread just looking to understand why gear oil over the synthetic 20w50? or is the Amsoil fine?

 

i just use one bottle of harley transmission fluid and have never had a problem

 

The gear oil is used because it is in the transmission, which has high shear stresses on the oil due to the gear action. Gear oil is better suited for this than engine oil since it has different additives.

 

This is all spelled out in the owners manual.

Formula+.

 

You can use ATF if you want, it's fine for your transmission and better for your clutch

 

Atf is better than the oil designed to be in the primary?

 

No, I suggest using factory fluid.

 

i always use formula + just wanted to hear the logic behind using aft.

 

I stuck with Formula+ too for primary (M1 20W50 for engine).

 

Barnett and some other clutch manufactures recommend ATF for the clutch plates, I've had zero problems using factory fluild with those after market clutch packs.
I see nothing wrong using different brands of fluild, just make sure it's designed for the primary, I had huge problems with ATF. So I went back to factory fluid.

Now every one will chime In With , how much better it shifts with ATF and the old, if it works in a cars tranny, it will work in my bike.