synthetic gearbox oils

Peter Hagen · Mar 17, 2023

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) ?

Onder · Mar 18, 2023

I guess the only thing that springs to mind is GL4 v GL5. Does the GL5 adversely affect the bronze bushes? Or does the increased wear on said bushes mean less than the preservation of the gears themselves?
We probably need an expert here.

concours · Mar 18, 2023

"30 hp transmission behind a 60 hp engine"

robs ss · Mar 18, 2023

concours said:
"30 hp transmission behind a 60 hp engine"

Maybe - but last pretty well, unless abused/neglected, don't they?
You have TT's on your's then - obviously?

robs ss · Mar 18, 2023

concours said:
"30 hp transmission behind a 60 hp engine"

Sorry for the narky response to your post - but, really?
The guy was asking for advice - please explain how your post helped?

concours · Mar 18, 2023

robs ss said:
Maybe - but last pretty well, unless abused/neglected, don't they?
You have TT's on your's then - obviously?

Don't listen to a thing I say.
I got nothin.

I have no experience whatsoever with machinery, gears, synthetic lubricants or Nortons.
Sorry to have written something you didn't approve of in your "oil thread".

concours · Mar 18, 2023

robs ss said:
Sorry for the narky response to your post - but, really?
The guy was asking for advice - please explain how your post helped?

Please explain why you are asking me WHY I POSTED SOMETHING?
👮🏻‍♀️

Because most people only want to hear what they think they already know.
SOME use critical thinking, problem solving.

concours · Mar 18, 2023

robs ss said:
Sorry for the narky response to your post - but, really?
The guy was asking for advice - please explain how your post helped?

"REALLY?"

What are you bringing to the gearbox oil discussion?

concours · Mar 18, 2023

robs ss said:
Maybe - but last pretty well, unless abused/neglected, don't they?
You have TT's on your's then - obviously?

If "abusing" consists of changing up from 1-2, at 6,000 rpm and rolling on full throttle.

Is anything other than parade speed dawdling considered abuse? Do tell......

"obviously" I don't have "TT's"
I can only write small checks

Schwany · Mar 18, 2023

I suggest using the search function. This topic has been discussed in one form or another many times like everything else related to owning a Norton. You'll get more opinions with a search.

I've run synth and standard gear oil of all kinds in my P11 AMC gearbox. Makes little to no difference as long as it is gear oil. The gearbox does like to be treated like a baby, but mine has survived many shifts at 6000 RPM. I do change gearbox oil like I change engine oil though... Frequently

I've had my AMC gearbox apart 3 times, but not because it was broken. I just changed out the stock mainshaft for a Commando mainshaft to get proper engine sprocket and clutch sprocket alignment with an NEB clutch. All good in there. I have settled on cheap automotive 80-90wt hypoid oil in gallon jugs. Matter of fact what I put in there last night was from Walmart. lol Shifts the same and the bushes are not worn out because of using standard automotive gear oil. My best guess is the reported broken gearboxes would have broken no matter what oil was used in them.

There will undoubtably be disagreement on what my not so cool choice is, but I am not caring. I do me.

Craig · Mar 18, 2023

These oil topic threads always cause issues , well as long as I been here , must be close to 20yrs now , oil has been controversial always …. have at it , I’m going for coffee

concours · Mar 18, 2023

robs ss said:
Sorry for the narky response to your post - but, really?
The guy was asking for advice - please explain how your post helped?

Craig said:
These oil topic threads always cause issues , well as long as I been here , must be close to 20yrs now , oil has been controversial always …. have at it , I’m going for coffee

Lol, ...and on every other forum that uses lubricants.
😎🏁

mean gene · Mar 18, 2023

I can only say what I know, Red line oils definitely make Harley's shift smoother! Norton's I have tried many, all shift the same! I don't do any long distance so, longevity I don't know. Never noticed abnormal wear.

bill · Mar 18, 2023

I don’t care what oil is used in the gearbox . The parts are pretty much crap along with as stated a 30 hp box asked to handle 60hp. On another note the worst thing you can do is a BIG counter shaft sprocket. The better way is to overdrive the primary as much as you can than adjust the secondary to get the overall ratio you want. By doing this it reduces the input torque and gives a better advantage on the output side. Win win for the gearbox. It is not an oil issue and no matter what you use it will not cure gear tooth spalling, teeth breaking or shafts breaking

Fast Eddie · Mar 18, 2023

mean gene said:
I can only say what I know, Red line oils definitely make Harley's shift smoother! Norton's I have tried many, all shift the same! I don't do any long distance so, longevity I don't know. Never noticed abnormal wear.

What Redline do you use, this ?

Tornado · Mar 18, 2023

Fast Eddie said:
What Redline do you use, this ?

View attachment 104829

I believe that stuff is identical to the Redline Heavy Shockproof, just aimed at the HD crowd, hence the black bottle and V-Twin call out, plus an 'enhanced' price point compared to shockproof white bottle and comparatively friendly pricing.

concours · Mar 18, 2023

Tornado said:
I believe that stuff is identical to the Redline Heavy Shockproof, just aimed at the HD crowd, hence the black bottle and V-Twin call out, plus an 'enhanced' price point compared to shockproof white bottle and comparatively friendly pricing.

That is what Redline customer service told me, just a different label. I had trouble finding it locally, she directed me to an H-D shop.

robs ss · Mar 18, 2023

concours said:
Lol, ...and on every other forum that uses lubricants.
😎🏁

Under your (substantial) posts:

mean gene · Mar 18, 2023

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)

gpzkat · Mar 18, 2023

Craig said:
These oil topic threads always cause issues , well as long as I been here , must be close to 20yrs now , oil has been controversial always …. have at it , I’m going for coffee

What kind of coffee do you recommend?