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 1940-2125ppm.
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 2125ppm 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?

[Tracksnblades1]

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?

Yeh, that’s is a neat video.. It tests different oils,  “single” rings, and cylinder preparation wear in the absence of combustion by products and other real effects. Better than nothing but falls short of real time testing with the Big Bangs included..

** borrowed from others documents in the ASTM papers** cherry picked to reduce size G77 & G206 lab machines***

**Limited Real-World Simulation: The primary limitation is that these tests cannot replicate all conditions that exist in a fired engine simultaneously. Key factors missing or simplified include:
Combustion Products: The chemical effects of combustion gases, soot particles, and corrosive byproducts on the oil film and surfaces are not present.
Complex Dynamics: Full engine dynamics, such as piston secondary motion (tilting/slap), complex oil flow in the entire system, and varying component temperatures and pressures, are difficult to simulate perfectly on a bench rig.
Wear Distribution: While some advanced simulators can replicate the high wear at the top ring reversal point (TRRP) where the oil film is thinnest, the overall wear distribution throughout the cylinder bore can differ from a real engine.**

I like watching Lake Jr’s videos, very informative.  But keep in mind he’s a well sponsored and paid voice…? 🤔

And Rotella’s additive package and others are engineered and real world tested to complement each other.. Rotella’s calcium isn’t going to bleach the ZDDP off the lobes and lifters..

[PeWe]

Yeh, that’s is a neat video.. It tests different oils,  “single” rings, and cylinder preparation wear in the absence of combustion by products and other real effects. Better than nothing but falls short of real time testing with the Big Bangs included..

  high wear at the top ring reversal point (TRRP) where the oil film is thinnest, the overall wear distribution throughout the cylinder bore can differ from a real engine.
.......

You seem to know a lot about oils and engines. How to make them run as good as it gets.

- How much zinc do you think is good for a modified CB750 type of engine?

Shimmed race springs make some rocker pressure against cam.
More valve lash might help oil to lube the cam too.

CycleX spring comment from their webpage
Stock valve spring installed height (1.455ish) spring pressures with these Kibblewhite ENV-008 springs are:
65lbs (no shims)
80lbs (.060 copper shims)
180lbs @ 375 lift (no shims)
200lbs @ 375 lift (.060 copper shims)


- When too much?

I guess 1800-2000ppm will be fine.

Ca: 2500ppm or more is easy to get when adding zinc additive. My K6 is on the high side right now

[Tracksnblades1]

Yeh, that’s is a neat video.. It tests different oils,  “single” rings, and cylinder preparation wear in the absence of combustion by products and other real effects. Better than nothing but falls short of real time testing with the Big Bangs included..

  high wear at the top ring reversal point (TRRP) where the oil film is thinnest, the overall wear distribution throughout the cylinder bore can differ from a real engine.
.......

You seem to know a lot about oils and engines. How to make them run as good as it gets.

- How much zinc do you think is good for a modified CB750 type of engine?

Shimmed race springs make some rocker pressure against cam.
More valve lash might help oil to lube the cam too.

CycleX spring comment from their webpage
Stock valve spring installed height (1.455ish) spring pressures with these Kibblewhite ENV-008 springs are:
65lbs (no shims)
80lbs (.060 copper shims)
180lbs @ 375 lift (no shims)
200lbs @ 375 lift (.060 copper shims)


- When too much?

I guess 1800-2000ppm will be fine.

Ca: 2500ppm or more is easy to get when adding zinc additive. My K6 is on the high side right now

Your every bit my equal PEWE.. Hell I been telling everyone since 87, Im just struggling to be average in this over achieving and complicated world.. But on a serious note about your guess.. I’m sure your Spectrol engineers had their game face on when they selected the additive package and ZDDP type for their HD oil offering.. Just thinking out loud, I’m guessing a super high detergent diesel oil like Rotella (with an anti foam additive that foams less than a non-additive non-detergent oil does) detergent’s will bleach the diesel type ZDDP off before a car/motorcycle oil will. Because it’s detergent and additives package has to deal with the combustion by products of a diesel and no wet clutch or belts..

I think you’ll choose as well as I can, Kemosabe..🎯
If your oil’s engineers selected it, I wouldn’t worry about it..
It had to pass a lot of scrutiny and cost control to make it in the bottle..
Hope you have a prosperous 2026..
Keep posting the good stuff..😇🎯

[Tracksnblades1]

PEWE..

Check out the link in your spare time..It may get you started better than I can..
I don’t know how accurate the info is, but it should get you enough terminology you can research
it adequately through ASTM publishings..?

https://bobistheoilguy.com/forums/threads/primary-vs-secondary-zddp.295359/

[PeWe]

Interesting link
It covers ZDDP versions for all kind of oils, not only motor oils.


I copied the part below of a comment that also mentions the viscosity as a vital part. 
(The context is drag racing engines where they use thin oils to get more power

Moly on the other hand can be bad for the wet clutch. I have read somewhere that there are different types.  Not all bad for clutch.)


"If your priority is wear (especially cam & tappet wear) then your priority should be to use a heavy oil containing not a lot of shearable VII; something like a 'tight' 20W50 for example.

I used to get paid to sell additives and yes there's a lot you can do to counter wear with Zinc & Moly.
However, any formulator worth his salt will tell you that, in terms of anti-wear, there's no substitute for non-shearable high viscosity & the presence of some genuinely heavy base oil in the blend.

By all means slap in a goodly amount of Zn & Mo on top but go heavy! BTW, it won't matter what type of ZDDP you use at these kinds of temps as both will be well above their respective activation temperatures."
##
......

I have found interesting info on Porsche forums. The older models are aircooled and even the later (1980's) are specified to use 20W-50 as CB750.

https://rennlist.com/forums/928-forum/709018-oil-and-zinc-additive.html

Post #6 has nice info.

+ From post #37
 A long interesting post where the oil's film strenght is mentioned as a top priority.
(I have read this on other forums too. That's why I believe in V-Twin oils where the oil film has to work with a much longer stroke than a CB )
.....

Zinc is used as an extreme pressure, anti-wear additive. But, zinc “DOES NOT” build-up over time like some type of plating process. For those who have actually taken an engine apart that has been running high zinc oil, you know that you don’t find a build-up of zinc that looks like some sort of coating or sludge build-up. Zinc does NOT work that way. And zinc is not even a lubricant until heat and load are applied.
Zinc is only used when there is actual metal to metal contact in the engine. At that point zinc must react with the heat and load to create the sacrificial film that allows it to protect flat-tappet camshafts and other highly loaded engine parts.

Another thread:
Post #9 below
https://rennlist.com/forums/928-forum/1335715-bruce-and-sean-buchanan-buchanan-automotive-on-oil-tt-and-tbf.html

Post #16 below
https://rennlist.com/forums/944-turbo-and-turbo-s-forum/973124-oil-question-for-my-951-a-2.html

Post#5 below
https://rennlist.com/forums/968-forum/854352-968-engine-motor-oil.html


I have read another thread where the guy Buchanan/Jet951 had commented the viscocity importance and also found how quick it could degrade.
Castrol oil tested after not long use. Also how Porsche engines failed quickly due to low viscocity oils.

The Porsche engines are used as street cars plus track days.
Like a modified CB750 with occasional speeding rides.

So, what have I learned now? ,;D
- Viscosity  (not too low)
- Film strenght (V-Twin oils must have that)
- ZDDP that last. I'll follow the Spectro mineral example of 1900ppm level,  Redline ester synth only 100ppm more.

[PeWe]

One more!! D

Post #8
https://rennlist.com/forums/944-turbo-and-turbo-s-forum/973124-oil-question-for-my-951-a-2.html

With a workshop oil pressure gauge connected on a last century Porsche & at 95 deg cel oil temp , every 5w-50 we have tested in the last 15+ years reads a lower oil pressure than a 20w-50 ( same brand )
........
A typical 5w-50 is really just a 5w-40 with more Vii's ( viscosity index improver's )
......
See post #24
More true observations and conclusions based on years (decades) of experience.

[Tracksnblades1]

PEWE:

Slow down. I’m struggling to keep up with just trying to be average..😜 You’ve piled the homework on me…🤕
I think we’re on the same page. you’ve picked out that high quality and proper viscosity base stocks don’t need a lot of help from additives..⭐️🎯

.I’ve been to several oil seminars and a few in house informational training sessions through the years.. I was very young at the first one. Not a lot has really changed. And as you pointed out, the high quality base stock is the key in the formulation. Poor base stocks are still poor regardless how good the selected additive packages help them..

 For instance the 5w-40, I was taught the ideal base stock would be a 25-30weight depending on where the oil would be sold and used. Then the appropriate additives would be added to make the chosen base stocks flow like a 5w oil when cold and likewise a viscosity modifier to make it act like a 40 weight when hot.. The worst example being the same 5w-40 formulated from a 5weight base stocks and then adding enough viscosity modifiers to make the 5weight act like a 40w when hot. And then sold to the end user for use at the equator….🤢

I’ll read up on the homework you’ve assigned..😁
But I’m thinking your already on the right page…

And to think Detroit Diesels (2 Strokes) knew the viscosity laws way back in the late 30’s..Still recommends Straight 40 weight High Detergent. Nothing else can protect them as good. They do allow straight 30 weight HD when temps permanently dip below freezing. Kinda like the same time frame Aviation engineers knew all about 4valves per cylinder, Nitrous Oxide, EGR (for detonation control only no epa then) superchargers, turbo chargers, water/methanol injection, fuels, octanes, oils, and on and on and on…. And we still argue about this SH*T instead of reading what been published, tried, and proven since the 30’s..

Seems like we’re all quilty of trying to reinvent the wheel when there’s several good ones already..😇
And these guys and gals do this everyday, week after week, month after month, and year after year for 30+ years,
 and we all know what’s best….😏

[Tracksnblades1]

Ell PEWE, last I’ve read on air cooled Porsches, they was into the 60weight stuff…
Nearing top fuel stuff…?

[Kelly E]

PEWE:

Slow down. I’m struggling to keep up with just trying to be average..😜 You’ve piled the homework on me…🤕
I think we’re on the same page. you’ve picked out that high quality and proper viscosity base stocks don’t need a lot of help from additives..⭐️🎯

.I’ve been to several oil seminars and a few in house informational training sessions through the years.. I was very young at the first one. Not a lot has really changed. And as you pointed out, the high quality base stock is the key in the formulation. Poor base stocks are still poor regardless how good the selected additive packages help them..

 For instance the 5w-40, I was taught the ideal base stock would be a 25-30weight depending on where the oil would be sold and used. Then the appropriate additives would be added to make the chosen base stocks flow like a 5w oil when cold and likewise a viscosity modifier to make it act like a 40 weight when hot.. The worst example being the same 5w-40 formulated from a 5weight base stocks and then adding enough viscosity modifiers to make the 5weight act like a 40w when hot. And then sold to the end user for use at the equator….🤢

I’ll read up on the homework you’ve assigned..😁
But I’m thinking your already on the right page…

And to think Detroit Diesels (2 Strokes) knew the viscosity laws way back in the late 30’s..Still recommends Straight 40 weight High Detergent. Nothing else can protect them as good. They do allow straight 30 weight HD when temps permanently dip below freezing. Kinda like the same time frame Aviation engineers knew all about 4valves per cylinder, Nitrous Oxide, EGR (for detonation control only no epa then) superchargers, turbo chargers, water/methanol injection, fuels, octanes, oils, and on and on and on…. And we still argue about this SH*T instead of reading what been published, tried, and proven since the 30’s..

Seems like we’re all quilty of trying to reinvent the wheel when there’s several good ones already..😇
And these guys and gals do this everyday, week after week, month after month, and year after year for 30+ years,
 and we all know what’s best….😏

I used to drive a Detroit Diesel super turbocharged(a turbo bolted to the top of the supercharger) 8V 92 in a 79' Freightliner conventional. That truck was badass. I had to do the oil changes on it. Get the hand truck and wheel out 9 gallons of Chevron Delo 400 15w/40 oil. It was the most fun truck I drove ever.

[scottly]

You were a truck driver Kelly?

[Kelly E]

You were a truck driver Kelly?

Yep, one of several careers I had. Truck driver, mechanic, cabinet maker, remodel carpenter, electromechanical assembly, cook and Mr Mom. I probably missed a couple.

[grcamna2]

You were a truck driver Kelly?

Yep, one of several careers I had. Truck driver, mechanic, cabinet maker, remodel carpenter, electromechanical assembly, cook and Mr Mom. I probably missed a couple.

Kelly,I enjoyed when we spoke about your many truck driving jobs,and a few of the skills you used to deliver loads when it was difficult.

[Tracksnblades1]

PEWE:

Slow down. I’m struggling to keep up with just trying to be average..😜 You’ve piled the homework on me…🤕
I think we’re on the same page. you’ve picked out that high quality and proper viscosity base stocks don’t need a lot of help from additives..⭐️🎯

.I’ve been to several oil seminars and a few in house informational training sessions through the years.. I was very young at the first one. Not a lot has really changed. And as you pointed out, the high quality base stock is the key in the formulation. Poor base stocks are still poor regardless how good the selected additive packages help them..

 For instance the 5w-40, I was taught the ideal base stock would be a 25-30weight depending on where the oil would be sold and used. Then the appropriate additives would be added to make the chosen base stocks flow like a 5w oil when cold and likewise a viscosity modifier to make it act like a 40 weight when hot.. The worst example being the same 5w-40 formulated from a 5weight base stocks and then adding enough viscosity modifiers to make the 5weight act like a 40w when hot. And then sold to the end user for use at the equator….🤢

I’ll read up on the homework you’ve assigned..😁
But I’m thinking your already on the right page…

And to think Detroit Diesels (2 Strokes) knew the viscosity laws way back in the late 30’s..Still recommends Straight 40 weight High Detergent. Nothing else can protect them as good. They do allow straight 30 weight HD when temps permanently dip below freezing. Kinda like the same time frame Aviation engineers knew all about 4valves per cylinder, Nitrous Oxide, EGR (for detonation control only no epa then) superchargers, turbo chargers, water/methanol injection, fuels, octanes, oils, and on and on and on…. And we still argue about this SH*T instead of reading what been published, tried, and proven since the 30’s..

Seems like we’re all quilty of trying to reinvent the wheel when there’s several good ones already..😇
And these guys and gals do this everyday, week after week, month after month, and year after year for 30+ years,
 and we all know what’s best….😏

I used to drive a Detroit Diesel super turbocharged(a turbo bolted to the top of the supercharger) 8V 92 in a 79' Freightliner conventional. That truck was badass. I had to do the oil changes on it. Get the hand truck and wheel out 9 gallons of Chevron Delo 400 15w/40 oil. It was the most fun truck I drove ever.

That’s the big girl for trucks..They have a 20/149 series for the big jobs…😳
I only have a 453 in a 1990 Vermeer T600D track trencher. Bought it with 3.9 hours on it from the USAF..
It came with a foot thick binder of service records..? 3.9 hours..? I don’t know if it was boiler room service records or real ones..?

Any way the following pictures are what I was referring to about the 40weight DD OEM requirements…
Borrowed on line but my manual for the 453 is the same…

[PeWe]

I like to collect real experiences.
A very  long milage stock CB750 on Spectro 20W-50 mineral is one good example.

Trickier to find long time use as 100.000 km with a modified engine, higher compression, hotter cam and high spring pressure. Always a reason to upgrade/repair.

The Porsche forum had info that supported my needs. Flat tappet cams with high spring pressure.

I got thoughts about my 836 setup the K6 got to 1984. The bores wore rather much during ca: 55.000 km. Hard rides on German Autobahn,  4 vacations should have better oil than Castrol GTX2 and similar I suppose.

I have heard about multigrade oils based on very thin oil. Additives increase the viscosity.
Oil will turn back to the thin oil with  bad bearing support

My car has an Audi 1.8 L turbo charged engine.  (Modified program).
A known oil to bitumen/sludge construction. Only 3.7 L oil with big filter.
I have noticed that oil must be changed within 8000km. At 10.000km  oil is much thinner.
0W-40 or 5W-40 synthetic. All not PAO class.
I think Aral Supertronic 0W-40 is a PAO oil.

I have seen motorcycle oils 10W-50 and 15W-50.  I'll stay away from them.

I hope more good experiences can continue to fill this thread.
Bad experience is good info too

[jlh3rd]

I do continuing research by reading, listening, and investigating oil threads.
My new toyota says to use 0W-8...really?....I've been researching that like crazy. Getting through all the "fluff" about "best oil" takes work.
Things I've learned...or believe....Car manufacturers only care about their corporate fuel mileage standards, they could care less about my engine longevity.
Our vintage bikes need the zinc that was in our original oils back in the day. (Rotella).
The wider the spread of the oil viscosity label ( 0w-8, 5w-40, etc.) , the more "plasticizers" you have per oil molecules by volume, so that should be avoided. I remember the controversy concerning 10W-40 even back in the late 70's - 80's. My first introduction to oil analysis.
Viscosity shear point/ longevity is critical......so no 10,000 mile oil changes for me.
Amsoil is a mineral oil and from most legitimate tests is quite a good oil. But you'll pay.
Base stock does matter. Quality filters matter.
No "api doughnut" rated oils in my vintage bike.
Hands on builders/rebuilders opinions matter.

There are dozens upon dozens of oil thread/ websites out there.......good luck to us that care.
🫤

[PeWe]

I think new vehicles are victims of the "green  fever"
Bikes that are tuned way to lean. Pigs to cruise in lower speeds, legal speeds.
I heard one Indian FTR  1200 is factory   tuned to an AFR of 14.7.
He need to take the bike to a tuner that modifies the ECU when removed from bike.
Booster plug not an option when ECU has at least 2 engine temp sensors and several mappings the ECU use.

Another guy  with a KTM could trick the ECU with a booster plug so ECU reads lower engine temp to run richer. Better flowing K&N filter that compensates the higher revs.

Thin oils in car engines for less resistance taking less fuel.
I doubt those engines will live long.
Most "green stuff" today does not work.

It must be youtubers or forums that show the bad and good oils for those cars.
I think it was a US car where engines destroyed really quick. The solution was another oil.

My old Audi I bought when 3 years old has 0W-30 as original oil. I gave it 0/5W- 40  as quick I could.
"Longlife" service interval is a real joke. Why change oil at 25.000 km when 10.000 km can be too long interval?  Turbo and small amount of oil shortens the intervals.

Audi USA has charts of approved oils with viscosities.

Ethanol in fuel another thing making engines to run worse. It must end up in  more pollution when the combustion is not complete.
Sooty valves and  chambers must indicate bad things.

[denward17]

All this oil talk, any recommendations?

I'm currently using the following based on suggestions from the forum, without any knowledge of oil......
Rotella T4 15w-40 for fall/winter/spring times when I ride (mineral).
Bel-Ray 20w50 for hot summer time rides (mineral).

Could I get by using Rotella T4 15w-40 all the time, in like 90+ F temps?

[scottly]

All this oil talk, any recommendations?

Reply #141 in this thread:
http://forums.sohc4.net/index.php/topic,6895.125.html

[denward17]

All this oil talk, any recommendations?

Reply #141 in this thread:
http://forums.sohc4.net/index.php/topic,6895.125.html

Well, you can't argue with that kind of mileage, I think I will start using the Spectro 20w50 conventional oil  after my current stash is used up.

[PeWe]

Why not try direct? The other oil can wait.

CB750 gearbox feels fine when shifting gears with Spectro 20W-50 Heavy Duty mineral

I had planned to change oil at 4500 km in my K2. I  changed at 5500km. Oil still felt and looked good.  I'm sure that 6000 km will work fine.

Redline (20W-50) another good oil. My K6 has got that.

I can not resist trying other oils too, often mixed with one quart of Redline as an additive.

[ofreen]

CB750 gearbox feels fine when shifting gears with Spectro 20W-50 Heavy Duty mineral

Yes.  I looked at the 750's maintenance log to see when I started using Spectro 20w50 - it was in 1998. By that time, we had been in southern Idaho for 5 years, so I had some experience with the summer heat around here.  I noticed right away that the usual hard shifting and difficulty finding neutral with other oils (mostly Honda HP4 and Castrol 20w50)  in stop and go traffic was no longer happening with the Spectro oil.  Even toward the end of the oil change interval where the other oils would get pretty bad.  Performance with Spectro was so good that I extended oil change intervals to 4000 miles for a long time.  These days I change it every 3000 miles, and the filter every other oil change.  I hadn't done one for a while, so out of curiousity, I cut open the last oil filter I changed in October.  I took a few photos, but haven't gotten around to posting them yet.  I was pleased to see how little debris there was in the filter media after 6000 miles in an engine that is closing in on 174,000 miles.  I see Dave started an oil filter thread, so I will try to post them there in the next day or so.

[PeWe]

CB750 gearbox feels fine when shifting gears with Spectro 20W-50 Heavy Duty mineral

Yes.  I looked at the 750's maintenance log to see when I started using Spectro 20w50 - it was in 1998. By that time, we had been in southern Idaho for 5 years, so I had some experience with the summer heat around here.  I noticed right away that the usual hard shifting and difficulty finding neutral with other oils (mostly Honda HP4 and Castrol 20w50)  in stop and go traffic was no longer happening with the Spectro oil.  Even toward the end of the oil change interval where the other oils would get pretty bad.  Performance with Spectro was so good that I extended oil change intervals to 4000 miles for a long time.  These days I change it every 3000 miles, and the filter every other oil change.  I hadn't done one for a while, so out of curiousity, I cut open the last oil filter I changed in October.  I took a few photos, but haven't gotten around to posting them yet.  I was pleased to see how little debris there was in the filter media after 6000 miles in an engine that is closing in on 174,000 miles.  I see Dave started an oil filter thread, so I will try to post them there in the next day or so.

Greg, you are the good example here. Really long time and distance testing of Spectro 20W-50. Bike is still running without obvious needs of restore.

This is also a good example when adding extra ZDDP additive in other oils with less amount of zinc. Find the working level.