I have been using AMSOIL 20W-50 in my Vision since about 2,500 miles and it is far superior to the Victory oil. The Vision 106 runs much smoother, cooler and shifts a lot smoother. I change my AMSOIL about every 5,000 miles unless I am on a road trip and I have gone as much as 8,000 miles before changing oil. AMSOIL will breakdown less in doing 8,000 miles in 15 days all long duration riding than doing 5,000 miles largely around town or in short rides over several months. With the miles I ride I am changing oil at least every 60 to 90 days. When Victory says change oil every 2,500 miles they are looking at the fact that many riders only put that many miles on per year.

Since Victory suggests using their 20W-40 oil if you are going to change to different oil it is most important to stay with the lower viscosity number they recommend. Too low of a viscosity (thin or light) = Metal-to-metal contact (friction and wear), poor sealing and increased oil consumption. Having a higher number on the high end of a multi-grade oil is ok. This is why I use the AMSOIL 20W-50 instead of their 10W-40. AMSOIL told me to use the 20W-50 and that their 10W-40 oil is mostly for water cooled engines.

VaParadox - 2008-12-28 3:44 PM ok, ive jotted down all of your info but no one listed an amsoil filter model etc. anyone have that available? along with anything else i need to order?

The AMSOIL EAO13 oil filter is a perfect match to Victory's filter. The only other thing you should buy are the copper washers that go over the oil drain plug of the Vision. You can buy these from the Victory dealer and they run about $.90 each. I will sometimes use them for two oil changes but no more to be safe. So all you need is the oil, the filter and the drain plug washer.

This oil stuff can be confusing but I have provided some links that I think explain everything you want to know and more on the topic. The bottom line to me as it applies to what AMSOIL to use in the Victory Vision is the following:

• I talked to an AMSOIL technical person and he told me to use their 20W-50 oil and not their 10W-40 oil. He said the 10W-40 oil is primarily for water cooled motorcycle engines and the 20W-50 oil is designed for air cooled motorcycle engines. He also told me it is more important to match the lower number than the top number as the bottom number is the base stock of the oil that the multi-grade oil is built upon. 
  
• 20W-50 oil is much more stable oil than the 10W-40 oil as described in this article. This is one of the best articles on oil I have ever read. http://motorcycleinfo.calsci.com/Oils1.html

Here is another good article on oil that talks a lot about viscosity. http://www.smartsynthetics.com/motor-oil-viscosity.htm

Here is the web page on AMSOIL Motorcycle oils which also stats the 10W-40 is primarily designed for water cooled engines and the 20W-50 is for air cooled engines. Read the text related to each weight. http://www.amsoil.com/a/synthetic-motorcycle-oil

Here is another good article that again states the 10W-40 oil breaks down too early and why some manufactures don’t recommend it. It also shows a graph that depicts to what extent a lower base weight of the oil supports colder temperatures. http://www.aa1car.com/library/oil_viscosity.htm

A mechanic I know has had several oils tested for the amount of breakdown in motorcycle use in different temperatures and mileage and he said the 20W-50 does significantly better than the 10W-40 oil which supports what all of these articles say. I hope this helps.

Spock - 2008-12-29 7:09 PM

• .... He also told me it is more important to match the lower number than the top number as the bottom number is the base stock of the oil that the multi-grade oil is built upon. 
  

Spock,

I am still not quite convinced (read: hard headed).

The Oils1.html article that you referenced contradicts what the Amsoil guy told you with the following.  The 1st number is for cold starts.  Once the bike is running, it is the second number that represents the operational viscosity because the engine doesn't stay at or below the temperature of freezing water (at least I hope it doesn't).

"... So, the first number tells us the performance of the oil at or below the temperature of freezing water, and the second number tells us the performance at the temperature of boiling water. ..."

Also, the article seems to indicate that Synthetics do NOT suffer the breakdowns as indicated.  Amsoil seems to agree with this in their writeups where they state "... Amsoil has the best high temperature film strength of all oils tested ...".  Maybe the breakdowns you mentioned between 10W-40 and 20W-50 oils are more targeted towards dyno oils and not synthetic oils???

"Synthetic oils made from pure PAOs and/or Diesters typically have very few VIIs, so these oils are far less subject to viscosity breakdown due to shearing of the VII package. As a result, synthetics are far more stable in a motorcycle engine. "

My Amsoil dealer instructed me to stick with the operational viscosity rating that the manufacturer suggests.  He said Harley Engines requires/recommends 50 weight operational viscosity thus recommends to 20w50 for them.  Victory's operational visicosity is 40.  His recommendations are consistent with what Amsoil publishes on their MCF and MCV web pages for both HD and Victory and 20W-50 and 20W-40 ratings.

Here is a blurb from Amsoils 10W-40 (Click here for more information) page that you referenced.  This details page is more specific than the cover page.  (Note: They Include Victory and Include 20W-40 ratings).

http://www.amsoil.com/storefront/mcf.aspx

"AMSOIL MCF (a.k.a. 10W-40) is recommended for Honda®, Kawasaki®, Yamaha®, Suzuki®, BMW®, Husqvarna®, Victory® and other motorcycles where 10W-40 or 20W-40 engine oils or SAE 80W/90, GL-1 gear oils are used. Not recommended where an API GL-4 or GL-5 gear oil is required."

Here is the same blurb for Amsoil's 20W-50 (Click here for more information) page that you referenced.  This details page is more specific than the cover page.  (Note: They Omit Victory and Omit 20w-40 ratings):

http://www.amsoil.com/storefront/mcv.aspx

"AMSOIL MCV (a.k.a. 20W-50) is recommended for Harley Davidson®, Buell®, KTM, Ducati®, Aprilia®, BMW®, Triumph® and other motorcycles where 15W-50 or 20W-50 engine oils or SAE 90, GL-1 gear oils are used. Not recommended where an API GL-4 or GL-5 gear oil is required."

I am still not certain either way.  Amsoil's MFC and MCV web pages seem to be pretty straight forward with their recommendations, but web pages have been known to be incorrect.  I wish the Amsoil people (web, dealers, techs, etc.) would get on the same page with respect to VICTORIES.  I do not want to run the wrong viscosity in my Vision and would like to get the best performance out of my toys.

Sincerely,

Tim

Tim as I have said I am not an oil expert I have relied on what the supposedly exports have told me. I spent a lot of time talking to some of the top AMSOIL techs on more than one call and at the IMC show last month in Dallas, talked to two AMSOIL distributors and a tech that has sent in numerous AMSOIL oil samples from bikes for testing and they all told me to go with the 20W-50 versus the 10W-40 in my Vision.

They have said you don't want to go with a base oil lower than the factory recommended oil which in this case is 20W. If AMSOIL made a 20W-40 oil I would go with it but the 10W-40 oil is to light and breaks down to soon. The 20W-50 will also perform better in high temperatures.

I would riley on the oil manufacture because if the oil causes a problem in any way I am going to hold the oil manufacture (in this case AMSOIL) accountable. I might call AMSOIL tomorrow and ask them to put what they have told me in writing and email it to me so I have it for my records.

They have also said like their website points out the 10W-40 is primarily designed for water cooled motorcycle engines and the 20W-50 for air cooled engines. http://www.amsoil.com/a/synthetic-motorcycle-oil

If you find a technical person at AMSOIL that disagrees will what others at AMSOIL have said I would like to talk with them.  This has been a learning exercise already and who knows we just might become oil experts yet. LOL