Mobil 1 15w50 vs Mobil 1 15w50 Racing 4T

[chevy8]

Hi folks,

We're trying to understand if there is any difference between the two or if they are the same and just relabelled here in Europe, as all we have is the Racing 4T which says it's for motorbikes.

Race crate engine calls specifically for "Mobil 1 15w50" fully synthetic.
We've ran out of bottles that it came with (were from the U.S). The only ones we're finding over here are 4T motorbike version. Here is the 4T version https://www.opieoils.co.uk/p-807-mo...synthetic-4-stroke-motorcycle-engine-oil.aspx

We can't work out if this is the same oil, but relabelled/renamed for Europe (in the same way that Shell has Rotella in the U.S but it's called Rimula in Europe).

Perhaps 15w50 isn't a popular grade here for engines, but it has more of an appeal to motorbikes, hence adding it on the label for that reason? Or a different formula?

Any help would be much appreciated.

Thanks!

 

[RevvCats]

I don’t know the differences between those two oils, but I think the hot 50 weight rating is the more important part of the recommendation than the winter part.

Mobil 1 15w-50 has a stated KV100 of 18 cSt, a HTHS viscosity of 4.5, and zinc/phosphorus levels around 1200 ppm. Find a 0/5/10/15/20W-50 weight oil with similar hot specs like that and you should be fine.

Is it a Chevy crate engine? Corvettes and Camaros used to call for Mobil 1 15w-50 when hitting the track.

 

[cheesepuffs2]

Motorcycle version likely doesn't contain molybdenum in order to be wet-clutch friendly.

 

[f355spider]

Motorcycle version likely doesn't contain molybdenum in order to be wet-clutch friendly.

I think you are correct, as I used regular Mobil 1 15w-50 and the clutch slipped in my Kawasaki Ninja whenever I has the RPMs way up (over 7,000) and did a gear change. I switched to a Castrol 10w-40 motorcycle specific synthetic and no further issues.

 

[JAG]

The product data sheet in that link is from 2021. The properties are a little different from the latest PDS from Mobil 1’s American site: https://www.mobil.com/en/lubricants/for-personal-vehicles/our-products/products/mobil-1-15w-50

The motorcycle oil meets JASO MA and MA2 and I doubt the American M1 15W-50 would be able to…I bet it would fail the clutch-friction tests by being too low. I expect the motorcycle oil to be a good oil. Whether it is what you should use is something nobody here can answer without more information about your engine, what type of racing it will experience, and how much you are trying to optimize your oil choice.

 

[ka9mnx]

Motorcycle version likely doesn't contain molybdenum in order to be wet-clutch friendly.

Most oils oils for motorcycles with shared sumps have no friction modifiers, Not good for an automotive oil.

 

[SR5]

Most oils oils for motorcycles with shared sumps have no friction modifiers, Not good for an automotive oil.

I disagree.
A car engine and a motorcycle engine are fundamentally the same, they just have a different clutch and gear box set-up. On the car they are separate from the engine, while on many bikes the engine oil is also the clutch and gear box oil. But it's still engine oil for the bike, and it's still a regular spark combustion engine, with the same requirements as a car engine.

A friction modifier is not an essential component of an engine oil, and not all oils have them. It is a nice add that can make your engine a bit smoother and that's it. The heavy lifting of protection is done by the hydrodynamic lubrication of the base oil, here more viscosity protects better. If the oil film can't keep the engine in the hydrodynamic region, then it's the ZDDP that then protects the metal. They leave friction modifiers out of bike oil, simply to stop a wet clutch from slipping. Friction modifiers not being present doesn't trash an engine.

Bike oils are good engine oils with extra demands on them due to the shared sump design:
- shear stable VII to survive the gear box that can cut and shred lesser VII,
- extra ZDDP to protect the metal on metal contact in the gear box.

I consider motorcycle oils to be tougher and more shear resistance oils, than the average car oil. The have to do all the work of an engine oil, plus the extra work of a gearbox oil.

Over here Penrite makes number of shear stable, high zinc, friction modifier free, engine oils suitable for both cars and bikes. That's the selling point. I've been buying them for years and been using the same oil in my cars and bikes for years.

OP, you will be fine. If slightly less smooth. But still well protected.

 

[SR5]

The only ones we're finding over here are 4T motorbike version. Here is the 4T version https://www.opieoils.co.uk/p-807-mo...synthetic-4-stroke-motorcycle-engine-oil.aspx

That link clearly says the M1 15W50 4T oil is API SN, which says it's suitable for car engines. API SP adds a LSPI test for small capacity DTI engines, but you probably don't need this on a crate engine, and anyway this oil is heavy on ZDDP which is a powerful LSPI quencher.

It then goes on to say

• Optimised frictional properties allow consistent power due to reduced frictional losses and overall optimised balance of engine performance and fuel economy
• Exceptional wear protection to help extend engine life
• Outstanding thermal and oxidation stability provides fluid film protection at all operating temperatures to minimise deposit formation especially at the high operating temperatures found in air-cooled engines
• Outstanding low-temperature properties enable effective lubrication at low ambient temperatures to enable easy starts, rapid wear protection and reduced drain on starter systems
• Excellent detergent/dispersant capability for outstanding engine cleanliness and smooth and reliable operation
• Protects from rust and corrosion to ensure long life of critical valve train and bearing components

Basically, it's a well formulated engine oil. I don't see any problem.

 

[SR5]

Some related threads

Thread 'Why should i not use a motorcycle oil in a car?'

Jun 28, 2022

Over on the other side of the pond, we don't have Mobil 1 15W-50, however i would be able to get Mobil 1 15W-50 Racing 4T motorcycle oil for a reasonable price, there's a small parts store in my town that is closing and all the motor oils are 50% off or more, so i could get it for relatively cheap.
No cats or anything on the car in question, and it has a flat tappet cam... owners manual specs API SE 15W-40 or 20W-50 for my climate.

• FCD
• Replies: 27
• Forum: Passenger Car Motor Oil (PCMO) - Gasoline Vehicles

C

Thread 'Can I use Motorcycle oil in a gasoline car engine?'

Feb 8, 2022

Just out of curiosity.
AAP has on a closeout shelf, Valvoline Full Synthetic 15W50 motorcycle oil for ~$2.50/qt. I may uses(from time-to-time), a 15W40, 15W50 oil in the Firebird V8 in my signature however, I've NEVER used a specific motorcycle oil. I would buy up the shelf if I can. So, can I use Motorcycle oil in a gasoline car engine?

• CharBaby
• Replies: 35
• Forum: Passenger Car Motor Oil (PCMO) - Gasoline Vehicles

• 

Thread '4 stroke bike oils in cars?'

Mar 7, 2020

There is a new trend in another forum. This is: Why not use a 4 stroke motorcycle oil in a car?

The postive points should be:
- Better VI improvers, more shearstable, better addtive package (meant for gear lubriaction, to - better EP additives) and generally more robust base oils and so on.

In short, a high quality motorcycle oil should work well in a car that is driven hard and sporty, better than a average car oil. Especially in engines with timing chain.
Or you could mix it with you car oil, to boost it up, as some kind of additive.

I read often that you schould not use...

• ChristianReske
• Replies: 70
• Forum: Passenger Car Motor Oil (PCMO) - Gasoline Vehicles

 

[chevy8]

Thanks this has been helpful - I did think there would be something to do with wet clutches (I don't know much about bikes but have heard the term fairly often).
Application wise it is a 350 SBC crate race engine and yes this one does too "Corvettes and Camaros used to call for Mobil 1 15w-50 when hitting the track."
It sounds like we'll avoid the Mobil 1 4T that's available here as it from the comments it appears the formula is different.

 

[Jimiii]

Motorcycle version likely doesn't contain molybdenum in order to be wet-clutch friendly.

That’s not correct but a common myth. Redline motorcycle oils for example have higher moly amounts than many automotive oils.

 

[SR5]

While I agree that the formula is probably different for the two M1s, I don't consider it a significant difference that would cause any problems for you.

Basically you want a thick (high HTHS) oil for strong hydrodynamic lubrication, a 50 grade in this case. High ZDDP (zinc) for wear protection when it goes into boundary lubrication, the M1 15W50 has 1320 ppm Zn. It needs to be a synthetic oil to resist thermal breakdown under high heat loads. Plus the regular detergent / dispersant / corrosion inhibitor package that any API SP/SN/SL or ACEA A3/B4/C3 etc oil would carry.

You also want a narrow viscosity spread (e.g. 15W50) for lower shear and lower volatility, not a large viscosity spread (e.g. 5W50) which sacrifices shear and volatility for better cold starting in winter. I assume winter starting isn't an issue for you with that crate engine.

Sure, nothing wrong with importing the M1 you want. But I personally would look around for other suitable options. Maybe @FCD @ChristianReske @Jetronic know a few good options for you to consider.

Here is a link to the M1 zinc levels pdf

https://www.mobil.com/lubricants/-/media/project/wep/mobil/mobil-row-us-1/pdf/mobil-1---product-guide-rev-32.pdf

 

[SR5]

BTW if you are going to the trouble of importing oil, consider Penrite 10-Tenths Racing 15W50, it's a 100% PAO and ester full synthetic, 1680 ppm zinc, but still suitable for the street with a TBN of 9.8 and it's API SN rated.

 

[ka9mnx]

I disagree.
A car engine and a motorcycle engine are fundamentally the same, they just have a different clutch and gear box set-up. On the car they are separate from the engine, while on many bikes the engine oil is also the clutch and gear box oil. But it's still engine oil for the bike, and it's still a regular spark combustion engine, with the same requirements as a car engine.

A friction modifier is not an essential component of an engine oil, and not all oils have them. It is a nice add that can make your engine a bit smoother and that's it. The heavy lifting of protection is done by the hydrodynamic lubrication of the base oil, here more viscosity protects better. If the oil film can't keep the engine in the hydrodynamic region, then it's the ZDDP that then protects the metal. They leave friction modifiers out of bike oil, simply to stop a wet clutch from slipping. Friction modifiers not being present doesn't trash an engine.

Bike oils are good engine oils with extra demands on them due to the shared sump design:
- shear stable VII to survive the gear box that can cut and shred lesser VII,
- extra ZDDP to protect the metal on metal contact in the gear box.

I consider motorcycle oils to be tougher and more shear resistance oils, than the average car oil. The have to do all the work of an engine oil, plus the extra work of a gearbox oil.

Over here Penrite makes number of shear stable, high zinc, friction modifier free, engine oils suitable for both cars and bikes. That's the selling point. I've been buying them for years and been using the same oil in my cars and bikes for years.

OP, you will be fine. If slightly less smooth. But still well protected.

While I can agree with most of what you said, I wouldn't use an oil without friction modifiers in my vehicles. Who would want an engine that is "slightly less smooth"?

I think the problem with VII shearing has been overstated in recent years.

 

[SR5]

While I can agree with most of what you said, I wouldn't use an oil without friction modifiers in my vehicles. Who would want an engine that is "slightly less smooth"?

I think the problem with VII shearing has been overstated in recent years.

I think it’s sort of a balancing act, swapping a bit of this for a bit of that. I’ve used oils both with and without friction modifiers. To be honest the viscosity made a bigger difference to the smoothness to me than the friction modifiers. A thinner oil with friction modifiers or a thicker oil without, I would go the thicker oil.

Having said that, the smoothest oil I ever used in my car was Castrol Magnatec 10W30 A3/B4 semi-synthetic. It was Euro rated so thicker, but also with friction modifiers. So smooth that I had to glance down and check my engine was still running when stopped at a red light.

As for viscosity shear in a motorcycle gear box, I think it’s very important and makes a big difference to the quality of the gear change. You can definitely feel when an oil is shearing out when changing gears on a motorcycle.

 

[ChristianReske]

I am using the Liqui Moly 5w-40 Street race motorcycle oil in my car at the moment, for the second season.

https://www.liqui-moly.com/de/de/motorbike-4t-synth-5w-40-street-race-p000261.html#2592

Why? 1. It is real PAO, 2. It should have more robust, shearstable VII, 3. It should contain more EP additves, meant for the Gearbox, wich only could help, 4. It should contain more anti-foam additves, meant for use in a high reving engine with a gearbox, 5. The additive pack should be perfectly fitting for a high reving gasoline engine.

The oil has a API SP approval. Its safe for use with a catalyst and for sure not a longlife oil, it has a little bit lower TBN, but still good enough for 1 year or 12.000 Km. Surprisingly it is a Middle saps oil with 0.8 Sulphur / Ash . If somebody want´s friction modifier, Liqui Moly alse offers the ceratec additive wich you could add.

My car is a Honda S2000, the engine revs to 9000 RPM with a extreme piston speed. It´s much more like a motorcycle engine, compared to allmost all other car engines.

Looks like there are friction modifiers wich are wet-clutch friendly, Zinc is replaced with other AW additves and we really dont see everything in a VOA from Blackstone.

 

[Jetronic]

I'm using a motorcycle oil aswell, from Ravenol. Like @ChristianReske 's choice, it's a PAO/ester Blend, without VII, or some like PIB. Ravenol claims no shearing at all. Contains about 190ppm Moly aswell.

API SN though, it has a TBN around 8.

 

[FCD]

It would be interesting to see a UOA comparison on the same engine between for example M1 Racing 4T 15W50 and a car oil like Motul 300V 15W50, here in my area it seems a lot of racing and rally teams swear by 300V 10w40,15w50 or 20w60, in all kinds of engines.

 

[SR5]

Thanks @FCD @Jetronic @ChristianReske , that's what I was asking. What are some reasonable alternatives to M1 15W50 that are available in Europe.

Looks like you can get Motul 300V 15W50 (ester core synthetic), or RAVENOL RFS 15W-50 (PAO poly-alpha-olefin) full synthetic.

Liqui Moly Molygen 15W50 looks to be mineral based.
REPSOL RACING 4T 15W-50 is a synthetic, but another motorcycle oil.

With the Motul and the Ravenol, any idea of ZDDP levels?

Checking their online data sheets. The three below are synthetic car oils.

Motul 300V 15W50 (Ester)
KV100 = 17.9 cSt
HTHS = 5.3 cP
VI = 168
SA = 0.91%
TBN = 8.1
Flash Point (D92) = 228 C

Ravenol RFS 15W50 (PAO with Tungsten add)
KV100 = 18.0 cSt
HTHS = 5.3 cP
VI = 168
SA = 1.3%
TBN = 11.9
Flash Point (D92) = 248 C
Noack volatility = 5.5 %

Regular M1 15W50 (full synthetic, API SN)
KV100 = 18 cSt
HTHS = 4.5 cP
VI = 160
SA = 1.21 %
Flash Point (D92) = 232 C
ZDDP = 1320 ppm zinc / 1200 ppm Phos.

One metric I use to judge oil, is the highest HTHS for a given KV100. In this respect the Motul and Ravenol are very similar, and both clearly out perform the M1. Where as the M1 shines with proper API approval (I couldn't see it for the other two, but I didn't look exhaustively) and we get a clear and very generous ZDDP level for the M1.

 

[FCD]

The low ash content in 300V is surprising, i asssume it's not due to a lack of AW addditives but rather detergents and dispersants, i remember reading somewhere that Motul does not really recommend it for extended intervals of any kind.