Yet another oil topic

Previously AJ Walker wrote:

Hi, looking at changing out gearbox engine oil.. Then engine and forks.... I've read so much about oils... With so much conflicting info.

The Workshop manual says one thing, Andover Norton website another, internet threads different again...

I wanted to ask the opinions of those who own and use Nortons for advice what is for the best recommended main lubricants throughout?

Thanks.

Have owned three Commandos over the past forty threeyears and always used the following oils : Engine - 20/50 multigrade , Primary Chaincase- 20/50 multigrade , Gearbox- EP90 and Front Forks- 10W20.

If you are paranoid about clutch slip - wouldn't apply to Comando owners then - you could opt for tractor universal 10W-30 for the primary chaincase. It's used (amongst other things) for oil-immersed tractor brakes and is free from friction-reducing additives. Available remarkably cheaply from your local agricultural merchants.

I rate Opie Oils. If you like semi-synthetic, which I use in my 650SS, (after a full engine strip, sludge trap cleaned etc) and with a Commando-type external oil filter, thenhttp://www.opieoils.co.uk/p-3908-silkolene-super-4-20w-50-semi-synthetic-4-stroke-oil.aspx

In my T110, without having stripped the engine, and without a car-type oil filter, I use thishttp://www.opieoils.co.uk/p-841-silkolene-classic-silkolube-20w-50-mineral-engine-oil-for-cars-and-motorbikes.aspx.

I mention all that because 'modern' oils can have detergents which can flush out trapped sludge in your engine, and re-circulate it, without the benefit of a modern filter to trap it.

They also have a good range of 'classic' oils, which can be a bit basic, imo.http://www.opieoils.co.uk/c-1488-bike-classic-oil-range.aspx

If you mention you are in bike club; reel off as many as you can, you should get a 10% club discount.

Or, the NOC could contact them and register for it, if we haven't already, and make it legit.....

Previously AJ Walker wrote:

Thanks for the advice. Looks like using 20W/50 in both primary and engine makes sense to keep oil stock levels simple...

Anyone shop online for their lubes.. any particular brands.. synthetic, mineral etc.... maybe a trip to Halfords is required.

Hello you need Lucas Primary chain oil cooles and Lubricates and Dose not make the Clutch slip infact you find it help to make for a better clutch action , I use it alway now, Yours anna J

Having been thoroughly bamboozled by the foum and the multiplicity of contradictory options, I went with the advice of Nick at FD Motorcycles in Great Dunmow on what he uses in his Commando. Answer is 20/50 Morris Oil. The trick to avoiding clutch slip is to not overfill the primary case.

I have an RGM covenant fork damping arrangement and progressive springs in my forks and have been using 15W forkoil in them for some time. Its a pleasure riding along watching the forks tracking the undulations of our rubbish road surfaces, instead of the usual crashing and banging of the standard set up. Almost feels like riding a BMW !!

Previously james_fanning wrote:

Previously AJ Walker wrote:

Hi, looking at changing out gearbox engine oil.. Then engine and forks.... I've read so much about oils... With so much conflicting info.

The Workshop manual says one thing, Andover Norton website another, internet threads different again...

I wanted to ask the opinions of those who own and use Nortons for advice what is for the best recommended main lubricants throughout?

Thanks.

Have owned three Commandos over the past forty threeyears and always used the following oils : Engine - 20/50 multigrade , Primary Chaincase- 20/50 multigrade , Gearbox- EP90 and Front Forks- 10W20.

It seems no one likes the SAE 50 for the gearbox that is required by the Commando manual and the Dominator manual.

Interesting to note that most modern bikes have a combined engine and gearbox...................therefore having to share the same oil. Which often is a 10/30 or 10/40 or inbetween spec. So how do they get away without bathing their gears in EP 80/90? Also somewhere on one of these threads it mentions that EP 90 is just an SAE 50 oil with certain additives. If you can read it there is an interesting diagram in this month's (June) RH about recommended oils for classic bikes.

It does seem illogical to use 20/50 in a gearbox with old-fashioned clearances which were designed for 50 grade. Since the box does not get as hot as an engine, it's like using 20 grade.Modern gearboxes (like modern engines) are made to much tighter tolerances owing to computer controlled machine tools. This must affect the requirement for the oil.

Previously AJ Walker wrote:

Hi, looking at changing out gearbox engine oil.. Then engine and forks.... I've read so much about oils... With so much conflicting info.

The Workshop manual says one thing, Andover Norton website another, internet threads different again...

I wanted to ask the opinions of those who own and use Nortons for advice what is for the best recommended main lubricants throughout?

Thanks.

I've recently 'returned to the fold' after a 9 year gap without a bike on the road (the usual wife, house and kids syndrome) For about 10 years prior to that I ran a Mk1 750 Roadster as an 'everyday' bike and a Mk3 Interstate as 'Sunday best'. I sold the Roadster but luckily I decided to keep my old Mk3 in mothballs. I looked after her and have just recommisioned her. I mention this only because back then it was pretty much taken as read that everyone ran EP90 in the gearbox and Automatic Transmission Fluid in the primary chaincase (has using ATF - the type without friction reducers - become frowned upon whilst I've been away ?..) - I used it in both bikes (which had their original clutch plates) changed it regularly and never had a problem with clutch slip. Engine oil seemed to be more of a matter of choice, I used a monograde SAE 40 in the summer and a good 20w50 multigrade in the Roadster in the winter (primarily because I felt it got round the engine a little faster on cold mornings) Initially I used 20w50 in the summer too but found that I would get a slight 'weep' from the rev counter drives when the engines were good and hot, someone suggested the thicker SAE40 which seemed to cure the problem so I stuck with it (the lipped seal conversion was still in it's infancy I think.). Again, I changed the oil regularly (while it still looked clean !..) and I had no issues with engine wear and the inside of both engines were so clean you could eat your dinner out of them, but only if you like engine oil on your chips of course.. I think that, along with selecting the most suitable grade, regular changing of all lubricants is key. As for using semi or fully synthetic engine oils, it's a personal decision but I wouldn't use them myself because, as someone else has also pointed out, they were developed for use in modern engines which are CNC machined to a much higher standard than ours with closer tolerances requiring less lubrication. By the same token of course I would never dream of using SAE 40 in a new Norton 961 !..

I am in total agreement with John. Ihave been riding my 99since I was 18, no gaps despite mortgage, kids etc. SAE 40 in summer, 20W-50 in winter. I also use a cheap equivalent of ATF in the primary chaincase (no friction modifiers). Wear problems, negligible. I have never been convinced that thin oils suit older Nortons though that's probably just me being stuck in the 20th century.

At its last AGM, The Worshipful Company of Classic Motorcycle Webmasters narrowly avoided passing a resolution that the subject of oil may not be discussed on message boards.

To try another angle, rather than seek positive recommendations (which are legion), has anybody ever found an oil that has proved quite categorically to be detrimental in its application?

Previously David Cooper wrote:

It does seem illogical to use 20/50 in a gearbox with old-fashioned clearances which were designed for 50 grade.......Modern gearboxes (like modern engines) are made to much tighter tolerances owing to computer controlled machine tools. This must affect the requirement for the oil.

Oil is not a gap filler so I think clearances are irrelevant, especially regarding mating gear teeth. It does provide a film which, under very high pressure, can prevent the bearing surfaces (e.g gear teeth) of well designed components from coming into contact. Tappets on Commando's, and other engines, being an example of bad design. The fact that modern engines and gearboxes use 10w 30, for example, is proof that low viscosity oils can easily withstand the pressure generated in a high performance engine.

As far as I'm aware viscosity is an indication of an oils flow rate, not it's gap filling ability.

After switching to a modern synthetic thinner oil (special offer Halfords!) I find my Mercedes is now leaking through the seals. Imagine how the old Norton seals would cope. Mind you the din from the clattering motor would would put me off riding it..

"has anybody ever found an oil that has proved quite categorically to be detrimental in its application?"

Possibly!Modern oils are for modern engines with roller rockers, over head cams ETC.,ANDcatalytic converterswhich, in part,eliminate the harmfull combustionemissions. Modern oils have a lower zinc concentrate due to zinc having a detremental effect on the efficiency of the converters. Our old push rod engines rely on the zinc to keep the cams and followers alive, therefore only oils with the full zinc additive should be used. Some oil distributors (Valvoline for one) call them 'Classic Oil' for pre 1980 engines. Alternatively,zincoil concentrate is available which can be added to modern oil to be used in older engines which require it.

Previously Paul Knapp wrote:

Modern oils have a lower zinc concentrate due to zinc having a detremental effect on the efficiency of the converters. Our old push rod engines rely on the zinc to keep the cams and followers alive, therefore only oils with the full zinc additive should be used. Some oil distributors (Valvoline for one) call them 'Classic Oil' for pre 1980 engines. Alternatively,zincoil concentrate is available which can be added to modern oil to be used in older engines which require it.

According to an ex-oil industry employee, Mr C Bovington, this is not correct. If you search 'zinc oil' in the top left search facility you'll find it's been discussed before and that modern oils are fine in old bike engines. I only use modern oils and I've had no problems with poor lubrication.

Please remember, Classic oils are a nice little earner for the oil marketers and so sometimes they are economical with the facts. The issue of Zn ( = Zinc Di alkyl Di thio Phosphate) levels is also a red herring. Protection of the cams and followers depends on structure of the ZDDP as well as concentration. Some modern oils have lower levels of ZDDP than previous ones, but they must pass exactly the same fired engine tests as the higher concentration ones. The current European approval test is run under conditions much more severe than any we will encounter, ( I chaired the working group which developed it) . If you look up the specification sheets of many of the classic oils, you will find that not only are they low Zn oils but also low in detergency to keep your pistons clean and to neutralize the harmful acid produced by combustion of the fuel and by oxidation of the base oil, but are low in every other performance area.

A decent modern 20W50 or 15W50 is perfect for all Norton Twins. Use and enjoy!

Previously webmaster wrote:

To try another angle, rather than seek positive recommendations (which are legion), has anybody ever found an oil that has proved quite categorically to be detrimental in its application?

ATF in Mk3 primaries is not a good idea as it rapidly trickles past the automatic tensioner plungers (no seals there) and after a short period, start-up will be accompanied by the characteristic Mk3 flailing chain until enough oil has been thrown around to fill up the reservoir again.

Not wanting to muddy the water further, but an interesting read, though a bit too technical for me!

http://www.penriteoil.com.au/tech_pdfs/0Zinc%20Myths%20&%20Legends%20Nov%202014.pdf