Primary drive oil

So, which is the best primary drive oil would you reccommend? Or is it not really a big deal?
The Norton book sez SAE 20w-50 7oz.
Could it be that simple?
*Yes I know not to overfill the primary.
Put the oil in via funnel in the filler opening and when when the oil ceases to run out of the level hole then this is the correct 7 oz. I guess?
Oh, which is the best solvent to use to clean the inside of the primary case? (I will be doing some clutch work.)
*Yes I know not to overfill the primary.

Unrelated.
Do you have to use a small magnet to remove the clutch plates or is there another method?

Thanks again forum members!

ATF is the lube of choice for most of us. I put in a measured 7 oz, but will use the inspection plug per the rider's manual if not starting from dry.

My favorite clutch / primary cleaner is carb spray. I always have a big can of it around. Removing clutch plates needs 2 small hooked tools like dental picks or can be made from stiff wire.

Ideally use Ford type F with friction modifiers intended for applications friction plates or bands exposed to it. But anything that flows in/out of chain links enough works just fine. Decades ago racers got triplex chain failures/seizures using thick lube so had to back off to 20 grade maximum. Proper triplex tension cold allows chain bottom to flap some and I found best level to lube and not mess outsides or clutch plate was just enough so static chain sag just touched ATF or lesser grade lube. Never measured but 6-7 oz sounds about right to me. Gear box like ATF too where I use Dextron II if on hand. A bit too thin for my forks which I now like power steering fluid best.

If ya dig into chain and oils you'll find its main function is to flush metal grit out and cool, not really for sliding-rolling interface lube and chains don't really slide and roll much on their interfaces that are so strained ain't no oil in there left.

I don't know who "most of us" is or how this percentage was determined but I have always used engine oil.

I won't say most of us but many of us here in the UK use ATF (auto transmission fluid), it does a good job and is less prone to cause clutch drag than 20/50 or straight 20 grade,

Dave.

batrider said:

I don't know who "most of us" is or how this percentage was determined but I have always used engine oil.

Click to expand...

I don't know that anyone has ever counted but I would suspect that you are among the minority. Popular theory is that ATF keeps the clutch plates working better longer...personally I prefer air. Jim

Maxima MTL 75wgt gear oil extremely light eqivelent to a 20-30wgt engine oil, works for me.
Al

According to Brian Slark, former Norton factory Tech., he wrote in the latest Norton Tech digest, that all of you should have, that it is recomended to use ONLY 5 oz. of oil in the primary case. It's only there to help cool the stator and chain. Not the clutch.........


Tim_S

Throw away the chain and gears and get a belt drive unit. Quieter, lighter, one less (potential) oil leak and never have to worry again.