Synthetic M/C Oil
Elite HDF Member
Joined: Mar 2014
Posts: 4,214
Likes: 661
From: Prior Lake, MN
They probably sell a LOT more car oil and have more competition with other car oil brands. Maybe not so much competition with MC oils. Just my guesses.
Big Kahuna HDF Member
Joined: Apr 2008
Posts: 38,428
Likes: 896
....Great analogy...I'm dying here...
Road Warrior
Joined: Jun 2012
Posts: 1,672
Likes: 18
From: Orange, VA,
In bikes like metrics no you cant use automotive oil because the same oil that is in the engine runs thru the tranny and clutches, there are addatives that will make your clutch slip. In a Harley yes you can run it because the engine and primary are seperated, you can run automotive oil in the engine but not the primary, use a primary or motorcycle oil, they wont make your clutch slip.
Elite HDF Member
Joined: Apr 2009
Posts: 3,542
Likes: 161
From: Booming metropolis
In bikes like metrics no you cant use automotive oil because the same oil that is in the engine runs thru the tranny and clutches, there are addatives that will make your clutch slip. In a Harley yes you can run it because the engine and primary are seperated, you can run automotive oil in the engine but not the primary, use a primary or motorcycle oil, they wont make your clutch slip.
I found this on the Mobil 1 website. Google is a wonderful thing!
http://www.mobiloil.com/USA-English/...AQs.aspx#FAQs2
Also found this on the Amsoil website:
Are Amsoil synthetic motor oils different from Amsoil synthetic automotive oils?
Answer: Yes. In addition to withstanding extreme pressure, protecting against rust and withstanding high temperatures, motorcycle oils must be compatible with wet clutches. AMSOIL synthetic motorcycle oils are designed to meet the unique frictional requirements necessary for wet-clutch compatibility and provide maximum protection and performance in these applications.
http://www.mobiloil.com/USA-English/...AQs.aspx#FAQs2
Also found this on the Amsoil website:
Are Amsoil synthetic motor oils different from Amsoil synthetic automotive oils?
Answer: Yes. In addition to withstanding extreme pressure, protecting against rust and withstanding high temperatures, motorcycle oils must be compatible with wet clutches. AMSOIL synthetic motorcycle oils are designed to meet the unique frictional requirements necessary for wet-clutch compatibility and provide maximum protection and performance in these applications.
Road Warrior
Joined: Jun 2012
Posts: 1,672
Likes: 18
From: Orange, VA,
Yes because diesel oil does not have the addative package that most auto oils have.
+3 , I use the 15/50 also with formula plus in the tranny and primary.
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Grand HDF Member
Joined: Dec 2007
Posts: 4,999
Likes: 55
From: Bay Area
Not to comment on a syn vs auto oil, but I have to disagree on the 15-50 vs 20-50, the reason being auto technology has gone to very tight bearing tolorances thats why you see 0 wt, 5 wt, 10 and 15w. But harleys are sloppy when it comes to tight tolorances and at operating temps you will get poor lubrication with 15 w at high stress areas Just my .02
Road Master
Joined: Aug 2008
Posts: 759
Likes: 75
From: Vegas Baby!!
Not to comment on a syn vs auto oil, but I have to disagree on the 15-50 vs 20-50, the reason being auto technology has gone to very tight bearing tolorances thats why you see 0 wt, 5 wt, 10 and 15w. But harleys are sloppy when it comes to tight tolorances and at operating temps you will get poor lubrication with 15 w at high stress areas Just my .02