Amsoil 50/50 mixture, 2053cc engine

[arkainzeye]

This was my recently UOA while using amsoil motorcycle oil and mixing at a 50%-50% ratio of 10w40 and 20w50. This is on a 2005 kawasaki vulcan 2000 (2053cc-125ci) shared sump Vtwin.

5005 miles on the oil 17,371 on the bike
0.6qts makeup 20w50

alum 6
chrom 1
iron 29
copper 15
lead 6
moly 35
nickel 2
magganese 6
potass 2
boron 1
si 5
sod 4
calc 3413
magnesium 16
phos 1147
zinc 1438

sus vis @210F 73.6
cSt vis @100C 13.89
flashpoint 365
fuel 0.5
insulubles 0.3

TBN 7.5

here is a copy of what blackstone labs had to say about it.

Your mix of oils produced a viscosity reading in the SAE 40W range when checked @ 210ºF. 0.5%
of the sample was gas, which isn't that unusual for a motorcycle engine. It can be from idling or city driving.
Iron and copper improved as did their wear rate (ppm/mile), which is a good sign that no mechanical
problems are developing at 17,371 miles. The TBN was 7.5, lots of active additive left in the oil. Remember,
1.0 is considered too low a reading. Air and oil filtration (see silicon & insolubles) were normal. Try ~6000
miles for your next oil change.

 

[Titan]

It's "the bomb", as the last batch of kids just before the current batch used to say!

I love this mixture...and I use it a full year before changing it.

 

[DashRiprock]

What is the point? What is the advantage of this?

 

[arkainzeye]

"thicker" than the stock 10w40 and "thinner" than the stock 20w50. So you still get the cold starting flow of a 40w. too sum it up quickly.

 

[DashRiprock]

So, you believe that starting your bike with a 15w (for arguments sake) in the morning is going to make a difference in protection over a 10w or 20w?

Can you quantify the difference? Can you honestly say that a 15w45 is so different than a 10/40 or 20/50, that it is somehow going to make a measurable change to the engine of your bike?

Im not trying to be negative. Just trying to understand what the purpose is.

 

[JonS]

What does your manual call for?

 

[Titan]

This bike specs an X-40 weight. However, the transmission seems to shift better for many of us with an X-50 weight. For me, a combination of the two seems about perfect. The engine doesn't "need" a thicker oil than a 40 weight...heck, it might do OK with a 30 weight, but, that straight-cut big transmission doesn't seem to happy until it gets on the thicker side of 40.

 

[arkainzeye]

"Can you honestly say that a 15w45 is so different than a 10/40 or 20/50, that it is somehow going to make a measurable change to the engine of your bike?"

There is not 15w45... Its either 40 or 50. And as we all know, all 40 weights are not the same. Same goes for 50 weight. You can "Make" a thicker 40 weight by doing this mixture. It is STILL and always was a 40 weight. Just a hair under a 50 weight. Its "almost" like how amsoils 20w50 and Mobil 1 vtwin 20w50 are not the same "thickest" even though they are both 20w50's.. my manual called for 10w40 in certain temps and 20w50 from 0F above. So the bike could run either or. I live in PA so i dont feel 20w50 is needed but at the sametime i want something thicker than just straight 10w40 and so far the mixture has had great results. Where you can feel it is in the transmission.. keep in mind this isnt no little motorscooter this is a 125 cubic inch vtwin (2053cc ) engine. With enough torque to pull a small car.