motul 5w40 7100 oil affects bmw k1600 gtl engine

[wantmoretoys]

i have put 3000+ miles on the bike with Motul oil. ran fine, no issues. this was the first change since break-in oil from factory.

This year, changed oil to begin season with Bel-Ray 10W-40. almost immediately noticed positive difference- motor revs out quicker and has more power.

Has anyone else experienced this effect with Motul oil?
WHY would this happen? Thanks in advance for thoughts.

 

[Bonz]

Not doubting what you feel, but reality is there isn't or shouldn't be a real difference if you put the bike on a dyno with respect to the power and thus how it feels to you on a machine that size. Even if it's a few horsepower and a few foot pounds, which I would find unlikely, you won't be able to feel it.

Could honestly be the motor is simply breaking in combined with a fresh oil change, does make a bike feel smoother in my experience simply because the oil hasn't had an opportunity to sheer down which usually isn't noticeable because it happens incrementally over time.

 

[ZeeOSix]

Was the Motul also 10W-40? Even so, a different brand of 10W-40 could be slightly thicker when hot ("40" covers a range of viscosity at 100C), and/or it might have better anti-friction additives that would help the engine run freer (revs quicker) and maybe feel a bit smoother.

 

[CleanSump]

I experienced the same with Motul 10W-40 vice Yamalube and Castrol synthetic. I like the way the Motul retains shift smoothness longer so stayed with it. No idea comparing to Belray. A hoard always descends to state you can't hear or feel a difference. Reminds me of an engineer that I worked with that insisted his design couldn't be wrong. The machinist brought parts this guy designed that wouldn't fit together. The engineers response was to pull out his drawings to prove the machinist's calibrated micrometers had to be wrong, the part had to fit. LOL. Engineer wouldn't look at nor measure the parts. Just kept pointing to the drawing.

 

[Bonz]

I experienced the same with Motul 10W-40 vice Yamalube and Castrol synthetic. I like the way the Motul retains shift smoothness longer so stayed with it. No idea comparing to Belray. A hoard always descends to state you can't hear or feel a difference.

Lol, I think it's a hoard of one...

 

[BusyLittleShop]

This year, changed oil to begin season with Bel-Ray 10W-40. almost immediately noticed positive difference- motor revs out quicker and has more power.

Has anyone else experienced this effect with Motul oil?
WHY would this happen? Thanks in advance for thoughts.

Good narrative... here are my thoughts from 50 years in the saddle...

Are oils are graded by gravity flow, formally called Kinematic
Viscosity (KV) in accordance to ASTM D-445... its important to note
that this test is not a measurement of an oils thickness nor an oils
weight... its a measurement of time required for a fixed volume of oil
at a constant temp to flow under the force of mean old Mr.Gravity...
The rate of flow is expressed in Centistokes (cST)... the lower the cST
number the quicker the flow which usually mean quicker revs and more power...

First up is BelRay 10w40 it's KV or gravity flow measures 14.2 cST @ 100C

Next is Motul 10w40 it's KV or gravity flow measures 13.1 cST @ 100C

So if the numbers are correct (which can change per batch of oil) Motul
flows 1.1 cST quicker than BelRay... but the seat of your pants says
BelRey revs quicker and makes more power than Motul... there is one way
to declare a winner and that is what Bonz mentioned... take a dyno run...

There's definitely room for a bit of placebo effect, anytime we make a
change that we "expect" to impact performance in one way or another.

 

[ZeeOSix]

^^^ High Temp, High Shear (HTHS) dynamic viscosity (units of cP) is more important and telling of how an oil actually behaves in a running engine - not a ball bearing falling by gravity down a tube of oil. Parts are dynamically moving in a running engine, no metal balls falling by gravity, lol.

It's very possible that an oil with a lower KV100 can have a higher HTHS viscosity due to its VIIs and formulation. Also, every oil formulation has a somewhat different AW/AF ad pack, which can effect the friction level between moving pats in the boundry and mixed lubrication regimes. Look up the famous "Stribeck Curve".

I never see you in the oil forums (which still applies to motorcycle engines) where all this stuff is discussed, so it's obvious why you're stuck on only KV100.

 

[bulwnkl]

WHY would this happen?

Maybe you and your K like new BelRay better than old Motul (?).

 

[Gokhan]

The Bel-Ray EXP 10W-40 uses a mostly mineral oil, which will result in an a lot thinner base oil and a lot more viscosity-index improver (VII). The base-oil viscosity (HTFS) is what matters when it comes to motorcycles. You want a high base-oil viscosity and low VII content. I estimate HTFS to be a lot lower for the Bel-Ray than for the Motul 7100 4T 10W-40. HTHS is lower for the Bel-Ray as well. Stick with the Motul if you care about the durability of your engine. Good luck.

Estimated base-oil viscosity (HTFS) and VII content of selected oils

 

[KrisZ]

That would be one fine tuned buttdyno to detect HTHS or VI difference between oils of the same hot grade. I suspect placebo.

Motorcycle engines have a relatively small inertial mass when compared to car engines so they should be more sensitive to oil viscosity, but within the same grade, I’m not sure I buy it.

 

[FarmForce]

Old thread here .... when looking through the enthusiast forums you get a bit mixed reviews for Motul 7100 ... but the oil that really gets only good reviews is Motul 300V. It is an amazing motoroil and has had a big impact on shifting quality and clutch operation of my 2022 Yammi Tracer 9 GT. It is heads and tails above anything I have used in my 45 years of riding.

 

[kschachn]

Old thread here .... when looking through the enthusiast forums you get a bit mixed reviews for Motul 7100 ... but the oil that really gets only good reviews is Motul 300V. It is an amazing motoroil and has had a big impact on shifting quality and clutch operation of my 2022 Yammi Tracer 9 GT. It is heads and tails above anything I have used in my 45 years of riding.

But with Bel-Ray 10W-40 the OP “almost immediately noticed positive difference- motor revs out quicker and has more power.”

 

[Mackelroy]

But with Bel-Ray 10W-40 the OP “almost immediately noticed positive difference- motor revs out quicker and has more power.”

Maybe it was the cold weather and your jetting, or mapping, that produced the crisp feel, otherwise no reason I can think of.