I've got an 05' Fatboy (might sell soon for a 07' RK) and have been using HD-Syn 3 in the engine/primary/tranny and was thinking about going to Amsoil and was wondering if you guys that useAmsoil use the 20w-50 in the engine and primary or if you use the 10w-40 in the primary and if most use the Amsoil 75w-90 Severe Gear in the tranny ???

 

Use 20/50 in the crank and severe gear 75/90 in the tranny. As for the primary you will get many different opinions, some say not to use syn in the primary because it's too slick and will cause slippage, others say malarky. I personally don't bother with syn in the primary and just use Formula + which seems to work well for me.

 

Amsoil MCV 20w50 in the engine and primary, Amsoil SVG (severe gear) 75w90 in the Tranny. Amsoil does not include friction modifiers, the little gremlins that cause wet clutches to slip, to their MCV formula.


nogood o~`o

 

Go to the OIL Related selection, under the "all about oil" thread of thissiteand read. Maybe go to Amsoils site and read theoil test comparision.You probably won't choose Harleyoil again.
I wouldrun90wt gear lube in the tranny.

 

I use Amsoil in everything but the clutch.Barnett says no to synthetics there.Some people do not use it in the motors because they think it is too slippery for the roller bearings.Who knows? I for one have never heard of a case of burned bearings because of synthetics.

 

I read that on J&P's site and decided to ask Barnett directly.
Here is their reply:

Synthetic oil is fine to use with our Scorpion clutches and all of our other clutch plates as well. We do recommend that you use a 'primary specific' oil and NOT automotive oils. We also do not recommend the use of Harley's new Syn3 synthetic oil.
[/align]Other than that, the main thing to remember is not to mix synthetic oil with non-synthetic oil. If your clutch has already been run in one type of oil, do not change oil types until you install new friction plates. If you arebuying a new Scorpion clutch, just soak the plates in whatever oil you choose for about 10 minutes, wipe off the excess oil and install. [/align][/align]We have used many different oilssuch asRedline Racing ATF, HD's standard primary oil, ATF, B&M Trick Shift and Motulwith good results. [/align][/align]Thank you for your interest in our products.[/align][/align]Chris Taylor[/align]Barnett Tool & Eng.[/align][/align]I'm under the impression that the primary does not need high viscosity, in fact, using a thinner oil like Barnett says they use would ideal.[/align]B&M Trick Shift was awesome stuff back in the early 80s during my Drag Racing days, I might give that a try.[/align][/align]

 

Amsoil 20w 50 in all three holes............... Check out their site.

 

use thesevere gearin the transmission, and put the MCV20-50 in the crankand also use it in the primary onlybecause Iusually buy it by the case and its on hand and more convenient than chasing after the harley +stuff. I've not had any problem with it and my clutch seemsto work better finding neutural than the stuff that came stock in the primary when I bought the bike.

 

You never will, as that old yarn is pure baloney. When I first heard this in about 1996 I called Torington, who makes bearings including some for HD, and the engineer I spoke with said he hadn't heard it before but it was false. He said it might be a skating problem in a centrafuge, where there is no friction, but a frictionless environment is not found in internal combustion engines. I ran Royal Purple in my '96 RK for 106k miles, it ran like new when I traded it in last November, and the heads were never off. RP is about as slick as oil gets, and the bearings obviously didn't suffer because of it.