Topic: OMG an oil thread!!

[scottly]

I'm also a fan of Shell Rotella. It's non-detergent
 

Rotella IS a detergent oil! In fact, diesel specific oil has more detergent than standard oil, due to the dirty burning fuel.

[Godffery]

I'm also a fan of Shell Rotella. It's non-detergent
 

Rotella IS a detergent oil! In fact, diesel specific oil has more detergent than standard oil, due to the dirty burning fuel.

Oh...? Well now, that's news to me then. 

[HondaMan]

Rotela's diesel-rated oils are not detergent-y. It causes havoc in diesel engines if it foams.
When I worked in the oilfield this was a huge deal: guys got fired for ever getting it mixed up, and those big trucks used 4-6 gallons of oil per change. The V-24, 4800 CID frac engines used 32 gallons of it.

[scottly]

Rotella diesel oil has a high level of detergent. When a diesel engine is run with standard oil for any length of time, the rings get so gummed up with carbon that the engine develops "Enough blow-by to float a Cat-Hat over the breather". The reason people started using it in our old bikes and cars is because it still had the zinc in it, when they phased it out of oil for new cars.

[PeWe]

I'm also a fan of Shell Rotella. It's non-detergent
 

Rotella IS a detergent oil! In fact, diesel specific oil has more detergent than standard oil, due to the dirty burning fuel.

+17
Finally oil talk!!

I have read about diesel oils with their zinc content AND the detergents that clean the zinc off.

Modern oils have less zinc due to the catalytic converters.

I wonder how modern bikes use the good Spectro and Redline oils when they have cat's that must be short lived when zinc content is 1900-2450ppm.
I guess the vehicle inspections do not test motorcycles as cars .

That amount of zinc is good for our old bikes. Plus good viscosity, not too thin.

I have ordered zinc in small bottles for my oils with low zinc content.
https://ebay.us/m/oMpKDH

Not too much either.

[BenelliSEI]

I'm also a fan of Shell Rotella. It's non-detergent
 

Rotella IS a detergent oil! In fact, diesel specific oil has more detergent than standard oil, due to the dirty burning fuel.

Thanks for the info. Didn’t know that! I like to use around the farm as it is priced right. I also use it for “first starts”.

[britman]

Nothing wrong with a good oil thread......Always brings to mind the old saying about opinions and a certain body orifice.......

[lash]

Never gets old!

[Tracksnblades1]

Rotella diesel oil has a high level of detergent. When a diesel engine is run with standard oil for any length of time, the rings get so gummed up with carbon that the engine develops "Enough blow-by to float a Cat-Hat over the breather". The reason people started using it in our old bikes and cars is because it still had the zinc in it, when they phased it out of oil for new cars.

👍

+1 High Detergent oil.

And New Rotella T4 has more detergent than Old Rotella…
Run detergent oil in an engine with a full pressurized oil and filter system.
Non-detergent oil was used in old non oil filtered or by-pass oil filtered engines..
So the impurities would be trapped in the sludge and not recirculated…Since most were splash lubed babbit bearings you could manually clean the sludge out when you took a shim out of the bearings to quiet the knocks up every 3-5k miles or sooner if you ran the crap out of them..

[PeWe]

I searched for zinc content in motor oils.  "Flat tappet + zinc" and similar search.
Mostly www.bobistheoilguy.com  (forum)

Later oils have less. I was surprised about the highest levels. I thought it should be more zinc in the 1970-80's.

There are also people discussing too high zinc content.
I saw one article where a guy claimed that too much zinc will cover the bore honed surface causing oil burn.

Very high content for cam break in.

Our modified engines with race valve springs shimmed for high pressure PLUS an agressive cam profile.
This must need more zinc than a stock engine, right?

Spectro Heavy Duty Mineral is a proven good oil for a known bike on this forum. Stock CB750 without taking oil after more than 250.000 km. Zinc around 1940ppm.

Content as Redline has with 2450ppm might be needed with race cam, springs and race riding style.



*** API vs years and Zinc content ***

SQ Current
Introduced in March 2025, designed to provide protection against both fresh and aged oil low-speed pre-ignition (LSPI), improved timing chain wear protection, improved high temperature deposit protection for pistons and turbochargers, sludge and varnish control.
API SQ with Resource Conserving matches ILSAC GF-7A by combining API SQ performance with improved fuel economy, enhanced emission control system protection, enhanced low temperature pumpability and protection of engines operating on ethanol-containing fuels up to E85.


### The date is when the associated classification ended. ###
SP 2025
SN 2020
SM 2011
SL 2004
SJ 2001
SH 1996
SG 1993
SF 1988
SE 1979
SD 1971
SC 1967
SB 1951
SA 1930

Motor oils of the following API service classifications had the following amounts of Zinc in them

SM MAX 800
SL/SJ 1000-1400
SH 1000-1400
SG 1000-1400
SF 1000-1400
SE 1000-1200
SD 1000-1200
SC 1000-1200
SB 1000
SA 0

EDIT:
I have an SM rated motorcycle oil specified to have 400-800ppm of zinc.
Add zinc a must.

[grcamna2]

I was looking at some specs on Shell Rotella T4 15/40wt. and one of them is 1200ppm of zinc.

[PeWe]

I forgot to mention that the API classes I wrote are for  petrol engines.

Diesel engine oils have a different letter.

API categories explained: API categories for diesel engine oils follow a simple two-letter format, like CF-4 or CI-4. Here's what each part signifies:

First Letter (C): This denotes the oil's suitability for diesel engines (indicated by "C").
Second Letter: This represents the oil's performance level, with higher letters indicating better performance for modern engines.


https://me.caltexlubricants.com/en_me/home/learning/from-chevron/heavy-duty-diesel-vehicles-and-equipment/understanding-diesel-engine-oil-api-specifications-explained.html

More interesting details here:
https://penriteoil.com.au/knowledge-centre/Specifications/194/api-service-classifications/363


*** Wet clutch: JASO MA vs MA2 ***
My CB750 K6 970cc (+100whp, double torque numbers than stock)  on the edge of clutch slip will get MA2. (V-Twin oil). 
This despite of later K7/F2 clutch, glass beaded metal discs and hard Barnett springs, middle number -66-

JASO MA2 oil provides increased friction performance – essentially, more grip. That means the clutch lever will feel less progressive, almost like an on/off lever, which some dirt bike riders like. For some riders, an MA2 fluid might be a little too “grabby.”

More details here:
https://blog.amsoil.com/whats-the-difference-between-jaso-ma-and-jaso-ma2-oil/


Would be better to have a later bike's stock clutch that can be bolt-on with a minimum of modifications.

I wonder which clutch a 120whp setup need?
70-72mm bore + 69-70 mm stroke + better flowing head with bigger ID of inlet spigots.

[Tracksnblades1]

I was looking at some specs on Shell Rotella T4 15/40wt. and one of them is 1200ppm of zinc.

Yes. Shell states a maximum of 1200ppm Phosphorus. Generally testing between 1100-1200ppm for T4 with the triple protection additive package..

PEWE: good info.. Rotella lost its API certification when the maximum phosphorus content for catalytic converters went to 800ppm phosphorus maximum..

Also your info is the same I have heard for a long time.. the following is copied from google but it’s the same that our family lubricant engineer says..

**Too much ZDDP (Zinc Dialkyldithiophosphate) in engine oil creates a balance issue: while ideal levels (around 1200-1400 ppm) protect flat-tappet cams, excessive amounts (over 1500 ppm) can become corrosive, increase ash/deposits, interfere with detergents, harm catalytic converters, and paradoxically increase wear by causing spalling or pitting, making the "ideal" range crucial for classic engines needing high zinc but not modern ones with emission controls. **

Additionally there have been published articles of the different types of zddp used in low RPM diesel engines vs high rpm gasoline engines utilizing aggressive flat tappet camshaft profiles and heavy spring pressures.. remember most modern and older diesel have roller lifters.. Think old 855 Cummins and some old Cats even had roller lifters push rod activated
Fuel injectors too..

[PeWe]

More about zinc, phosphorus levels.
Flat tappet cam car engines have no wet clutch to keep out of slip.

So much of the recommendations about later car oils with other antifriction additives instead of high zinc levels can not be a choice for our old bikes.

Here a later article:
https://www.enginelabs.com/tech-stories/do-classic-cars-actually-need-high-zinc-oil-lake-speed-finds-out/

This oil guru on youtube is impossible to miss

It seems to be possible to use lower zinc level for a period since zinc has covered the grinding metal parts?