I have an 03 Road King Classic. What is the heaviest lube I can put in the primary. I'm running Lucas at the moment and prior to that formula. I notice that when hot both of those are like water. Can I put something heavier in that wont hurt the clutch? I know basically its a splash set up and really not for lubrication more so to just keep the chain wet. My chain is good, bearing fine, adjusted dead on but when hot its noisey. I know its the nature of the beast but when the bike is not a full operating temp, the primary is rather quiet till the lube thins out due to heat. Just looking for a weight number.

randy

 

That's the only hole I use the Harley brand fluid. Nothings going to keep it quiet, so just run what you want. 130,000+ on mine and it's all original inside except for the stator. Original clutch plates and compensator. Go figure










BOB

 

I run Mobil 1 4t racing 10w40, I've never heard anything from the primary.

 

Oil in the primary is for cooling more then lubing.I think with a heavy lube in there your going to have problems,especially with the clutch.try using a lube specific for the primary,like spectrol,redline,belray and so on.I also run mobil 1 4t racing in the primary,works great.you may also have a worn or loose chain.If your swapping oil maybe you should pop that cover and take a peek in there.check your ajuster shoe for deep wear marks.Ajust chain to spec.

 

it's hotter here than it gets there...

I use the primary+.

here's the big thing- the clutch plates absorb lube.
if you start changing lubes it is possible that you have a lube in the primary which is not compatible with the lube absorbed in the clutch plates- and you get slipping

better for the clutch that whatever you use from the day you buy your plates and soak them in lube, ( whatever brand) that you use the same type

as for primary- I had great luck with the hayden m6 on both of my evos- a smart easy $75 job. mine was related to my worn out shoes ( at about 50k) and the result gave much smoother downshifts and low speed operation.
the 09 has harley's auto tensioner and so far so good


Mike

 

+1 on checking the chain for correct tightness Switching oils isn't the answer , you could be hurting the clutch plates.

 

HD Formula+.

That is all..

 

It truly is fine with Formula. It's 50W. It heavy enough for the huge clutch hub bearing and inner primary roller bearing. No detergent and thin enough for the chain. It's all rollers. Put 200K on my last car running 0W-20.

 

I use primary +. I was told 1 lite or quart was good enough but my service manual calls for 38 Oz. So I add another 4 to 5 Oz. It shifts smoother and feels much better at slower speeds

 

The thicker oils will shift harder. I've tried a bunch and have settled on a mix of amsoil primary & atf(8ounce). I seen the formal plus when I drained a buds bike. I can see why alot like and use it. It has about the same consistenty as my mix.