hey guys..time for me to adjust primary chain, clutch, and change primary fluid. I know harley makes a primary oil..is it 10/40, 20/50wt? fossil or synth. scoot is a 06 EGC. my shovelhead doesn`t use oil in primary..any good substitute for harley oil...i use amsoil in crank..gear oil in tranny..

thanx, Rob

 

The amsoil you are using in the crank is what is also recommended in the primary. The 10/40 or 20/50 can be used in the primary.

 

You can use almost any 10W40 motor oil or even ATF in the primary. All you are doing is lubeing the drive chain and cooling the clutch. There's no sense in spending the extra $$$$ for a synthetic there. I use ATF in mine (Dextron) and haven't had any problems. Before dising the ATF, consider the cluth pack makeup. It's almost identical to an auto transmission clutch pack, and the thinner fluid has less drag than a heavier weight lube.

 

I use Castrol GTX 10-40. Using any synthetic is just a waste of $$$$. Harley's Formula+ is dino oil and a good choice for the primary, but is still more expensive than any other dino oil you can use.

 

The primary fluid that HD sold for years is nothing more than hydraulic fluid. That's right, just like you put in a farm tractor. ATF is totally different, but works well, just a bit thinner, may transmit a little more noise and disspates heat quicker.

I haven't seen any the last few times I was in a dealership and I don't know if they even still offer it. All they have here now is 20-50 syn for all 3 holes.