synthetic gearbox oils

Shock proof 90-140 I think went to ck and have none on shelf. By the way their primary oil is waaaay to thin IMHO. I use shock proof in primary and they really quite down! Belray second choice.. What are we looking for when someone claims Hypoid oils will attack bronze/brass bushings. (I know opening a can of worms)
I think it is the sulphur - but not certain
Hypoid oil is completely unnecessary in an AMC box.
It has special additives to minimise wear from hypoid bevel, often helical, gear meshing. Hypiod gears are simply bevel gears where the axes don't intersect - common in many old differentials. It is done for practical space issues but creates extra sliding at the points of gear contact.
 
Since new I have been running the oil that is recommended in my workshop manual, Hypiod gear oil oil, yes I had the dreaded layshaft bearing failure at 12k miles not the oil fault that was in 1979 and a few months later I put my Norton into a shop with tuning problems, my kick starter always went loose on the shaft after a few kicks but wasn't too bad but this shop because it got loose the bastard welded my kicker to the shaft and didn't notice they did so and a few months later the kick start shaft broke at the pawl end of the shaft, I blamed the weld job for that and new shaft and pawl brought, so not the oil fault, well to this day I am still running the same Hypiod gear oil and my GB has well over 160k miles on it, but in the 43 years since the KS failure I have only been in the GB to replace worn kick start pawl 4 times the last time I replaced the KS gear where the KS pawl ingaged the kick gear was the reason the pawl kept wearing out.
Other than those times I still running all the original bronze bushes and I only change the GB oil when I have to go into the box other than that all the orginial gears are still good after 46 years of running with Hypiod gear oil and I haven't been inside my GB for over 20 years maybe longer can't remember but it still changes smoothly with no clunks or bangs and so no need to go into my GB, every so often I look inside the inspection cove to see the oil level is and a feel of the oil, it's always clean and feels good between the fingers.
Gear box oil isn't like motor oil it don't get contaminated and no need to change it all the times so am using what works for me.
 
I think the best gearbox/engine oil is decided after reading up on all the oil companies sales brochure/specification sheets.... and that then... has you convinced that "this oil" is best for you/your machine & peace of mind...
No oil or lack of ...on the other hand has catastrophic consequences
Look after it and keep it wet n sticky :)
 
righto Nortonites heres one I hope has not been beaten to death already, can't find any threads to Synthetic oil use in gear box on this site?
Has anyone experienced adverse performance issues in the gearbox using synthetic oil such as Nulon or Lucas (Northern Australia) ?
Thanks to all for input. It would appear there is no tried, tested or science behind any solution . A blend of Belray and Lucas has been suggested which I will try and post my opinion on this post at some stage.
Cheers stay shiny side up
 
Thanks to all for input. It would appear there is no tried, tested or science behind any solution . A blend of Belray and Lucas has been suggested which I will try and post my opinion on this post at some stage.
Cheers stay shiny side up
There are many old post on this subject...https://www.accessnorton.com/NortonCommando/what-oil-in-gearbox.5954/
 
Thanks to all for input. It would appear there is no tried, tested or science behind any solution . A blend of Belray and Lucas has been suggested which I will try and post my opinion on this post at some stage.
Cheers stay shiny side up
I use the Belray thatā€™s designed for sportsters, it works well. Iā€™ve just bought some of that Lucas additive to experiment with this year.
 
Not that civet catshit stuff??
Civet oil, is the glandular secretion produced by both sexes of the Viverridae (Civet) species....I wouldn't stick that in ya gearbox either...šŸ¤£šŸ¤£
Apparently is good for perfume and beverages...
 
Civet oil, is the glandular secretion produced by both sexes of the Viverridae (Civet) species....I wouldn't stick that in ya gearbox either...šŸ¤£šŸ¤£
Apparently is good for perfume and beverages...
No, no, no - I mean that Kopi Luwak stuff - Jack Nicholson talked about it on Bucket List.
 
Kopi Luwak is the world's most exclusive (and most expensive) coffee. The main factor of its high price is the uncommon method of production. It is produced from coffee beans which have been partially digested by the Indonesian palm civet and then shit out. Whatevs. Pass.

I wouldnā€™t use Shockproof or. GL5 oil.

GL5 will break down yellow metals. I also think is Sulfur that is the culprit?

I only used Redline Shockproof for a year. I don't remember what weight it was or even if there were different weights at that time. I would guess it was 15 years ago.
It did stop any migration of the oil down the input shaft, but when I found the bushing was loose and pulled it apart I found the outer bushings were dry and the shaft was blue from heat. I went back to ATF and have stayed with it since.

If it's good enough for the manual trans in this, it's good enough for me.
View attachment 12992
Best gearbox oil
 
Since it probably doesn't really matter that much which oil you use in the gearbox, I suggest you just use GL4 and at least you put the bronze bush worry aside. After all,
my Albion box is not even close to as robust as the AMC box and they recommend
using 40wt motor oil!
 
Without knowing anything about gearbox oils, I simply use what's recommended for the TTI box in most of my bikes.
They says: "Use 330ml of Motul Gear 300 Oil 75W90 GL-5 or Castrol Syntrax 75W90 GL-5 or similar spec oil. Do not use shockproof oils."
The Motul data sheet says it is compatible with all metals commonly used in gearboxes.
Horsepower handling of Norton gearboxes. Visiting Goodwood, I noticed that the midget race cars, using JAP and Manx engines all had Norton dolls head gearboxes. The gearbox which was introduced in the thirties when foot changing replaced hand shifting is obviously capable of abuse from rather heavy vehicles.
When I designed a 5 speed gearbox for sidecar racing, I learned that what breaks gear teeth is forces coming back from rear wheel on bumpy circuits.
 
GL5 will break down yellow metals. I also think is Sulfur that is the culprit?
Depends on which additives are used to obtain GL5, there are newer additives that are sulphur free and sometimes the oil is labelled 'Yellow metal friendly'. The Glacier Bearing Engineering Design handbook says that when their Copper/Lead bushes are used where the temps exceed 100C then GL5 type oils with sulphur should be avoided, so even with GL5 sulphur in the oil it will need high temps to start the reaction.
 
I had not logged in yet when I took a pix of a bottle of gearbox oil as I noted it was GL4
and synthetic. So although it is lighter weight than 90 it probably will do fine in a Norton box. Remember that some like ATF as it is light and gets into and around the bushes.
Just a thought...you could save a few quid and get Castrol TRANSMAX Manual EP 80W-90 1L 1 Litre Transmission Fluid : 12 quid
delivered for one litre. Probably do just fine!
 

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Just a reference point regarding the level of robustness of the commando gearboxes.
From all I gather from very reliable sources, the Cdo had a well known pattern failure of exploding second gear.
The operators were standard issue madmen immitating bank robbers in the hayday, like most young broncos were.

Now that those operators have morphed into fine, cultured gentlemen, and riding to meet other old duffers for lunch at a leisurely pace, the failure rate is much lower.

Ergo, the evolved perception the box is robust now.

Subjective as hell.

JMWO
 
I think the 60 horse (optimistic ) using a 30 horse (optimistic) gearbox is really the base of the discussion. The choice of lube MAY
assist in extending its life or even get you through the 6k shift a few more times but that is about it. When I did up my 74 ten years ago I bought a TTI five speed for it. Money long forgotten, lack of problems still with me.
 
I think the 60 horse (optimistic ) using a 30 horse (optimistic) gearbox is really the base of the discussion. The choice of lube MAY
assist in extending its life or even get you through the 6k shift a few more times but that is about it. When I did up my 74 ten years ago I bought a TTI five speed for it. Money long forgotten, lack of problems still with me.
My original (clearly controversial) post included quotation marks.

I didn't dream it up, but being very familiar with how design, engineering & manufacturing evolve, that old adage struck a chord with me and my box of broken parts.

Not 100% literal, it is a reminder of that gearbox having humble roots. And, the Norton heavy twin having progressed in power level over the years.

The intent was to STIMULATE THOUGHT.
Clearly it evoked some emotion.
 
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