Primary chaincase oil level and clutch slip

Previously norman_lorton wrote:

I did appreciate the article by James Leadbeater in the current Roadholder RH363. I know that some of us will have heard the comments made before, and he wrote a good review on this Forum a few months ago, but that article neatly pulls together the design failures when the Commando was first put together, and compounded by Norton's advice on chaincase oil level.

The Rotary clutch has many more plates (I forget how many but when you pull them out it is like one of those magician's tricks of never ending hankies) so they probably solved the slipping, but I know that gooing-up and drag were still the same problem.

I fully accept James' view that oil levels at a minimum necessary are the only way to delay the inevitable contamination and slip plus drag. But that leads to a big problem with the Mk3 where you must have enough oil to splash and fill the tensioner, and to fully lubricate the sprag that is shrouded behind the alternator rotor. I think we Mk3 owners are stuck with putting a decent amount of oil in, and taking the plates out for the usual wash once or twice a year.

The 'lowest necessary oil philosophy' is also hard to follow on older Nortons with pressed steel chaincases and the inevitable leaks and low usage. If you put 'just enough' in then after a few months the chain will be without oil.

My solution (and this is inappropriate comment on a Commando thread, but sorry) for an early ES2 is not to put any oil in the chaincase. I use Morris chain spray with an angled set at the end of the spray pipe, and with the bike running, on the stand, put a three second squirt exactly onto the moving chain. With the intermittent use that our older bikes get it only needs doing a couple of times a year. I also build the clutch with a wipe of this same, sticky grease on the rollers. Pity I cannot do the same on the Mk3.

Norm

Hi Norman,When i fill the primary on my MK3 i have the bike on the side stand with a piece of wood under the stand so the bike is just leaning off center and fill with 20/50 until the oil comes out of the level plug.i have done many miles without clutch slip or binding.Thanks Paul

Do not put a motor oil with its additives anti-friction, not well for the clutch especially for 850 MK3 the heaviest and which has most couple of commando