Oil from primary to gearbox

the Norton guys in your part of Australia advocate using 30 weight oil in your air cooled Norton?

because it is thinner it gets to places better

no offense Jed but perhaps you should consider that they are just flat "wrong"?

by their logic why not use ATF in the engine, it will get to places even better than 30 weight

Norton's engineers built the bikes, they know "more" than some guys where you live

they called for either straight 40 or 50 weight oil, and 50 in the hotter climates like yours

most Commando owners nowadays with better multigrades available use 20-50 non synthetic
or similar, and most everyone agrees that a 30 weight is simply too thin and becomes even thinner when it gets hot thereby not lubricating and removing heat as well as heavier weights

Jed said:

This oil is what the Norton guys use and swear by around here. Moves quick and gets where it's needed faster

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If Commando oil galleries were 10 feet long, then I might be inclined to agree.

What about when it's good and hot?

Jed said:

What blend do you think would be more appropriate for a warmer climate?

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SAE40 or 50 Mono. would be the usual recommendation unless riding in 'colder' ambient temperatures (below 0°C).

Jed you need to run 50 grade oil in your motor 30 grade is way to thin, use tranny oll (Brand F) in your primary and only use between 5 - 7 fluid OZ and no more it only needs to splash around to keep your chain lubed, the only way you will get primary oil in your gearbox is by over filling it, I put wheel bearing grease on my clutch rod and have never had any problems you don't need much on it and don't over fill your gearbox, I always messure my fluids and never rely on the over flow system, get a messuring cup that has fluid OZs on it and you never go wrong.

The poeple that told you to use 30 grade motor oil are wrong, maybe if you ride in snow every day, but its wrong, I run 50 grade all year round as well a oil cooler and have done so for 39 years, even moden bikes don't run 30 grade here in Aus, if you don't want to run a straight 50 go a good 20/50 grade, just ride it easy for about 2 ks for the oil to get to working temp, I run a straight 50 grade with STP treatment added for better protection.

Ashley

ashman said:

only use between 5 - 7 fluid OZ and no more it only needs to splash around to keep your chain lubed

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I wouldn't recommend using much less than the standard amount in a MkIII (Jed's) primary chaincase, as there has to be sufficient quantity of oil in there to keep the hydraulic chain tensioner hopper topped up so the tensioner stays primed.

Only need thin oil enough to get started and flow soon enough to surf cam lifers and if kept in cam lifter surf range then 30 grade is ok. I break in on cold 30 grade hi detergent and don't run initial tests to point to really fully heat oil and add that the thinner the oil the faster better heat carried away, such as newly burnishing in components. All references on oil will show the thicker it is the longer lasting oil and engine parts are though may cost some power & mileage to pump it. Please ask the seasoned Nortoneers what the basis of their experience is to suggest 30 grade. Just for technical accuracy there is no such a term as oil "weight" but is merely a carry over of a W added to old sold initially after WWII to denote single grades that had additives that helped flowing on cold Winter start ups. Racers will put in dangerous thin oil for the extra power but they don't let their engines below cam surf rpm very much and expect to use up parts fast like tires to get ahead.

I am only going by what my M11 runs so put what level the M111 needs in the primary.

Hi Steve, my problem isn't a problem worth dealing with at the moment. if it aint broken don't fix it. Id rather ride than fix something unimportant, especially that bloody seal as it is a pain to get at. When I have to remove the primary gear from the crank I will do that seal. Its waiting in my parts box. OIl doesn't leak through while I'm riding so I'm happy.
This problem mentioned above is a bit screwey isn't it. ????????????????????? F I I K
all the best, Dereck
P S let us know what you find. It used to leak oil from my 850 g/box so always overfilled it. Now it doesn't leak, its still over fill. Bugger. no probs that I know of though.

Change the primary engine drive-seal every time the primary is apart. Cheap insurance. MK 111 needs primary oil to proper level and proper grade. Earlier models less and thinner. :| Clutch pushrod seal kit yes.

hobot said:

Only need thin oil enough to get started and flow soon enough to surf cam lifers and if kept in cam lifter surf range then 30 grade is ok. I break in on cold 30 grade hi detergent and don't run initial tests to point to really fully heat oil and add that the thinner the oil the faster better heat carried away, such as newly burnishing in components. All references on oil will show the thicker it is the longer lasting oil and engine parts are though may cost some power & mileage to pump it. Please ask the seasoned Nortoneers what the basis of their experience is to suggest 30 grade. Just for technical accuracy there is no such a term as oil "weight" but is merely a carry over of a W added to old sold initially after WWII to denote single grades that had additives that helped flowing on cold Winter start ups. Racers will put in dangerous thin oil for the extra power but they don't let their engines below cam surf rpm very much and expect to use up parts fast like tires to get ahead.

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OK Ill get the reason for it when the guy is back in town
He's been building these things for about 40 years and has a couple of nice ones including a schmick cafe racer
In this area he has rebuilt 25 engines alone and the only caveat to using the 30 grade was more often changes
So far no burning oil in the system

Jed

Hope you can read this.

According to the lubrication chart in the MkIII workshop and riders manuals: "20w/50 or HD40" is the engine oil recommendation for: "...operating temperatures above 0°C (32°F)" and "HD50" for:"..above 32°C (90°F)". 2
"20W/50" for the primary.

Hi

That Page was taken fron The Norton Commando Riders handbook 750 68/69. And states" maintenance is reasonably simple" and. " well within the capabilities of the average owner". So read the manual follow the guidelines and your bike will start first time ,go like stink never loose a drop of fluid and it's free road tax.
Well the free road tax is true!

It also says that the primary should be filled until oil runs from the level plug hole. So maybe the manuals contain a bit of bollocks also. And maybe the guys who wrote the book were wrong.

Happy days

One theory the guidelines were fairly broad to ensure oils available at the local garage could be used in the day
Tests on 20/50 show the multigrades end up being 20 grade, worse than a straight 30
Oils may no longer be what they used to be but some of the old fellas who could build an old trumpie with their eyes shut or pick minor irregularities in early T'bird or trophy swear by the 30 SAE as well
Their recommendation was good enough for me (and some of the bike these guys have restored are astonishing) but the seed of doubt is well and truly sown and I will find out exactly why it is preferred over a straight 40 or 50 but suspect its to do with providing optimum lubrication
To date I have had no reason to be concerned as the engine runs sweet with minimal rocker clatter and provided correct oil level is maintained don't see why that should change

Jed

Jed said:

Tests on 20/50 show the multigrades end up being 20 grade, worse than a straight 30

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Which is presumably why the factory reverted to recommending monograde oil in preference to multigrade.

SERVICE RELEASE N3/59
All Commando

Worldwide (General Distribution)

Important amendments to all previously issued engine lubricant recommendations have now been confirmed by the Norton Development Department (see also Service Release N3/47 May '73).

H.D. SAE40 Mono-grade oils meeting A.P.I. service SE or SD performance level now form the preferred engine lubricant recommendations for both current and previous 750/850 models.

(SAE 30 equivalents for ambients below 32°F. (0°C.)

(SAE 50 equivalents for ambients above 90°F. (32°C.)

The previously recommended Multi-Grade lubricants continue with full approval for use, but it must be noted that all future recommendation charts in Rider and Workshop Manuals, and other Service publications will indicate H.D. 40 Mono-grade oils (A.P.I. SD or SE service rating) as the prime engine lubricant recommendations."

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" The previously recommended multi-grade lubricants continue with full approval for use". So if it says oil on the tin put it in.

Derek Wilson was going on his hols on an old cafe bike in the early eighties he had two bottles of oil round his neck tied with string when an old dear pulled out into him he was pretty smashed up two broken wrists etc and the oil was everywhere. Now I do believe one of the nurses did say to him he should be using monograde.

Happy days

http://www.penriteoil.com.au/products.php?id_categ=7&id_products=644 I hope that link works?

This is the oil you need in Oz Jed. Used by all the Commando owners that I know. As it is Penrite product it maybe the one you are using as it is referred to as HPR 30?


cheers

A little bit of knowledge can be dangerous!

Finally caught up with the guy who helped with my rebuild and got the oil info sorted
The 30 grade was only meant for use during the run in period (which has lapsed) you guys are right (not that I doubted it but I was confused)
Apparently this is to prevent the bore glazing over
It's my club bike so I haven't put that many miles on it (past run in) and not being heavy handed shouldn't have hurt it
The part of the info I missed was after the run in change to an SAE 40-70 penrite (or 40-60 as suggested by saddlesaw)

If not for being picked up on the point by LAB I may have gone on being blissfully unaware and feel pretty dumb for disregarding the manual so thanks all for helping prevent a possible disaster!

Jed