Engine/Primary/Trans OIL Question?
Banned
Joined: Sep 2009
Posts: 7,580
Likes: 7
From: The Internet (& Dyer, Indiana)
Might not have had anything to do with oil, but worthy of mention.
Also,..... amsoils own website does not recommend extending the intervals on motors with any modifications.
Pretty much makes it no better than dino oil in my case. Not cost effective with the shorty intervals.
Tourer
Joined: Aug 2008
Posts: 270
Likes: 1
plus the United States remains Venezuela's most important trading partner.
Last edited by Mav; Nov 14, 2010 at 09:38 PM.
Extreme HDF Member
Joined: Sep 2005
Posts: 11,615
Likes: 50
From: Baton Rouge, LA
Pretty much everyone agrees on 20w50 with a few suggesting 10w50 Mobile to save on the cost.
Many suggest 10w40. Oils without friction modifiers. ATF.
Most say 75/90 Gear Oil and a couple said 75/140.
None of this agrees with my service manager or my service manual.
I really would like to learn what works and why. Please just don't say what you use only, but WHY you use it. Give me a logical reason.
Primary: Most any fossil engine oil, preferably the cheaper varieties without friction modifiers. ATF and HD Formula+ are also fine, but the latter is obscenely expensive at $8/qt.
Tranny: Gear oil, synthetic or non-synthetic. Pick your viscosity, but the thicker varieties will run a bit smoother with reduced clunkiness. (If "clunkiness" isn't a word, it should be in the HD world.)
Road Warrior
Joined: Jun 2007
Posts: 1,788
Likes: 4
From: Here
There's a thread floating around called "Evo Rebuild" that has a guy who ran Amsoil for the last 40k miles. Motor is toast. Bearings are shot.
Might not have had anything to do with oil, but worthy of mention.
Also,..... amsoils own website does not recommend extending the intervals on motors with any modifications.
Pretty much makes it no better than dino oil in my case. Not cost effective with the shorty intervals.
Might not have had anything to do with oil, but worthy of mention.
Also,..... amsoils own website does not recommend extending the intervals on motors with any modifications.
Pretty much makes it no better than dino oil in my case. Not cost effective with the shorty intervals.
Just trying to get your statement in perspective.... What do you consider "extended drain"? 5000, 7500, 10000? How many miles do you go between changes?
I doubt you will find any mainstream oil that recommends extended drain intervals on modified engines either. They (any oil manufacturer) can't test all modifications to go out on that legal limb. I see Redline just says "extended drain intervals over other brands" and leaves it at that. Wonder what they mean by "extended"?
About the "toast" Evo... it's doubtful that the brand of oil caused the failure don't you think? A more likely scenario would be a minor manufacturing defect, assembly issues, abuse (overheating, lack of routine maintenance, burnouts, whatever) than the actual oil causing the failure. It just as easily could have failed using Brand x. I know all those engines that have "grenaded" have not all used the same brand oil. But then again, WTFDIK?
Outstanding HDF Member
Joined: Sep 2005
Posts: 2,600
Likes: 7
From: Minnesota
I think there is some confusion on Mobil oil recommendations. Mobil makes 2 different oils that some recommend. They are both synthetic. One is a motorcycle specific oil and one is a car oil that many people use in their MC with good results.
From Mobil's website;
"Mobil 1 V-Twin 20W-50 is recommended for four-cycle motorcycles that specify the use of a 20W-50 engine oil."
and
"Mobil 1 15W-50 fully synthetic motor oil exceeds warranty requirements for gasoline engines where an API certified oil is specified"
From Mobil's website;
"Mobil 1 V-Twin 20W-50 is recommended for four-cycle motorcycles that specify the use of a 20W-50 engine oil."
and
"Mobil 1 15W-50 fully synthetic motor oil exceeds warranty requirements for gasoline engines where an API certified oil is specified"
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Road Warrior
Joined: Jul 2009
Posts: 1,979
Likes: 2
From: Northern Colorado
20w50 motorcycle oil is a good all-purpose oil for the motor and it works well in the primary too but I think it is too thin for the transmission. I've used Formula+, Syn3, Amsoil 75w140 and Spectro 6 speed in the tranny and of all those Spectro worked the best and Syn3 was the worst, loud/violent clunk and lots of chatter.