10w30 vs 15w40 first impressions

[Luciano]

bike in my sig recommended oil 10w30 sj jaso-ma no matter what temps. Guess who sells it.

Decide to try a cheap conventional HDEO 15w40 CI-4/SL. 3 liters jug for R$ 39 (stands for +- 13USD).
At first i was afraid but hey it is just oil heh.
Clutch is fun now i mean it doesnt grab that much like previous mc oil. I used to balance throttle / "burning" clutch when shifting at low speeds.
Engine is really smooth and quiet
My left foot enjoyed it

Same 49 MPG

Then 1,250mi with 15w40 and all i can say is bike loved it! My wallet too

That was a great deal.

 

[Doog]

Lots of people run Shell Rotella 15w40 in their bikes with great results.

 

[dustyroads]

Good deal! I just bought an atv that will get rotella 15w40 based on the results I've seen in motorcycles.

Saving big money is a bonus.

 

[NeilR]

I use Rotella T6 in some wet clutch ATVs, it seems to work very well and is cheaper than "specialty" ATV oil.

 

[kmrcstintn]

Honda recommends 10w-30 as of 2007 for 'better fuel economy'

there are several 10w-30 HDEO's (at least in the US) that are applicable if someone wants to avoid motorcycle oil; some of these oils are Chevron Delo 400 XLE in 10w-30, Shell Rotella T-5 in 10w-30, and Motorcraft 10w-30 for diesel engines...all are 'cold weather' alternatives for 15w-40 diesel oils

the clue to using a 10w-30 successfully in a bike is to avoid oils that are designed for passenger cars that are rated as 'energy conserving' or 'resource conserving' which contain additives that might promote clutch slippage

10w-30's not rated as 'energy conserving' or 'resource conserving' are good alternatives to 10w-30 motorcycle oils

 

[BusyLittleShop]

Originally Posted By: kmrcstintn


the clue to using a 10w-30 successfully in a bike is to avoid oils that are designed for passenger cars that are rated as 'energy conserving' or 'resource conserving' which contain additives that might promote clutch slippage


You're welcome to warn against it but Energy Conserving or Resource
Conserving are not additives... its an API test that this "oil may
result is an overall saving of fuel in the vehicle fleet as a
whole"... there is nothing new in the oil to defeat a wet clutch...
what is confusing the issue is the fact that all motorcycle wet
clutches will reach a point in their life and start to slip EC oil or
non EC oil... have you noticed that no one complains about clutch slip
when the bike is new??? its around the 27K to 57K range as normal
containments build up to point you may find the clutch begins to loose
its grip... this is usually discovered by the owner during WFO (Wide
Fooking Open)throttle like during a quick overtake or at a track
day... in error one can blame the EC oil but its really the
contaminants on the clutch plates...


Example shows Mobil 1 additives are the same ones for EC 0w30 and non EC 15w50...

 

[Shannow]

Originally Posted By: BusyLittleShop
Example shows Mobil 1 additives are the same ones for EC 0w30 and non EC 15w50...


No, the chart that you are showing compares only elemental analysis of a limited number of oil components...and you can't have an "EC" 50 in the first place.

The components that are wet clutch not compatible are "friction modifiers", and you can't see them in a routine UOA. They are present in EC oils, as the lighter viscosity oils tend to allow more metal to metal contact (boundary lubrication), and the friction modifiers help prevent damage/scuffing to metal under these conditions.

As to not affecting clutches, it's common knowledge everywhere that FMs should be avoided for wet clutches/brakes.

To support my statements, I'll use Penrite Race series of oils. The 5W30, and 0W20 (really 16) are friction modified because of their lower viscosity...the 10W40 and upwards are not (they all have the same add packs bar the FMs.

10W40 - non friction modified, suitable for wet clutches.

5W30 - friction mofified, not suitable for wet clutches.

 

[BusyLittleShop]

Friction modifiers additives are only a small percent of the total oil product and help
the base oil do things that it otherwise could not... Additives fall into several basic
categories but Moly Phosphors and Zinc are the most often used friction modifiers... what
ever small percent of FM employed they will not defeat a wet clutch in good working order...

Some may warn at the possibility of clutch slip based on something not seen but I've been
using Energy Conserving Mobil 1 since 98 in Mr.RC45 with no clutch slipping due to oil
and it's a $27,500 homologated racer with a tall first gear good for 90mph that's known
to incinerate clutch plates...

 

[Bror Jace]

So, Luciano, are you going to try a 10W30 version of the same brand oil? I'm guessing the lighter weights will be a bit more difficult to find as close to the equator as you are.

It would be interesting to see if all the good drivability traits you've discovered continue ... and you get better fuel economy to boot!

 

[Luciano]

Already did that Bror Jace. Good stuff for no more than 2500mi when shifting becomes notchy. Shifting quality seems to be related with viscosity so I expect to run a longer OCI with 40wt.
Yep you're right. For example this autopart where I buy oils there is few 10w30 on the shelf.

It would be also interesting to see low wear metal figures from now on. Ok maybe that is too much to ask