View Poll Results: A poll
Voters: 5066. You may not vote on this poll
What Primary Oil is your Choice
Road Master
Joined: Jun 2006
Posts: 894
Likes: 6
i have the same basic bike. I run Red Line Shock Proof gear oil in the tranny and Shell Rotella-T 15W-40 in the primary and that really smoothed things out. I change the gear oil every 2-years and the primary fluid every year regardless of miles. I think the clutch contaminates primary oil quickly. I think the biggest improvement came with replacing the stock primary chain tensioner with the HB-125 hydraulic tensioner. The Harley shifts like my dirt bike and I never have a problem finding neutral like a lot of guys with new bikes do. Clunking is also reduced.
6th Gear
Joined: Jan 2017
Posts: 13
Likes: 0
From: Bowling green ohio
Just a update on what i did. I put 20w50 in the motor and primary. In the trans i put amsoil severe gear 75-110. It did quiet 5th gear whine a bit and it doesnt clunk as hard shifting into first. As well as neutral is easer to find
Stellar HDF Member
Joined: May 2015
Posts: 2,091
Likes: 304
From: mid Michigan
I put red line shock proof in my snowmobile chain case today, because of being happy with the results in the Harley transmission. Primary on HD waiting for spring to get the redline primary that's setting on the shelf.
Stage IV
Joined: Apr 2017
Posts: 4
Likes: 0
From: Centerville, UT
Since the primary has clutch friction disks the fluid should meet the newer JASO MA standard. I have found few motor oils meet this standard. I like the Amsoil 10W-40 motorcycle oil, and Mobil 1 10W-40 motorcycle oil which meets this standard. As long as it meets this JASO MA standard it will work.
Seasoned HDF Member
Joined: Apr 2010
Posts: 33,714
Likes: 3,723
From: Connecticut.
Since the primary has clutch friction disks the fluid should meet the newer JASO MA standard. I have found few motor oils meet this standard. I like the Amsoil 10W-40 motorcycle oil, and Mobil 1 10W-40 motorcycle oil which meets this standard. As long as it meets this JASO MA standard it will work.
Advanced
Joined: Nov 2014
Posts: 99
Likes: 16
From: Sweden
Seasoned HDF Member
Joined: Apr 2010
Posts: 33,714
Likes: 3,723
From: Connecticut.
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Novice
Joined: Jul 2017
Posts: 21
Likes: 0
From: Ohio
I just did the Mobil 1 V-Twin "in all 3 holes" scenario on my 2013 Wide Glide 103. I think it might shift slightly smoother, but overall no major differences. Finding neutral seems to be a little better now too, but it may be in my head. Absolutely no adverse reactions as of yet. Full synthetic gives me piece of mind and DIY is pretty cheap when buying it from Walmart.
