Not enough oil
Seasoned HDF Member
Joined: May 2008
Posts: 21,173
Likes: 12,740
From: South Carolina
The correct level.
Just fill the primary until the lube is at the correct level.
Just like filling a beer mug, you don`t need to know how much it holds, it doesn`t matter if there is already some beer in the mug when you refill it...
You just fill it to the proper level...remembering, overfill bad...
Seasoned HDF Member
Joined: May 2008
Posts: 21,173
Likes: 12,740
From: South Carolina
A little less is just fine. It`s a primary drive, the sprockets and chain sling the lube all over in there.
Ultimate HDF Member
Joined: Jan 2009
Posts: 5,016
Likes: 277
From: East Tn Foot of The Dragon
Drain it, install 1 qt, ride it. It will not make any difference in the primary.
Ultimate HDF Member
Joined: Jan 2009
Posts: 5,016
Likes: 277
From: East Tn Foot of The Dragon
I have been doing mine wrong for years. I have always set my primary level on the side stand.
Extreme HDF Member
Joined: Jun 2011
Posts: 10,216
Likes: 224
From: Glendale AZ
Upright, side stand whatever, 38 for regular draining, 45 when removing the primary cover.....it's not rocket science, just measure.
Supporter
Joined: Oct 2012
Posts: 1,242
Likes: 1
From: Farmingdale, New York
Yep, that's what I put as per the service manual. in fact I'm putting the Screaming Eagle heavy spring tomorrow morning and I'll be taking the primary cover off so I have 2 quarts of formula + at the ready to add 45 ounces. I'm also checking the Hayden tensioner I put in around 2 weeks ago too. we'll see how that's doing......
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Outstanding HDF Member
Joined: Jan 2008
Posts: 3,328
Likes: 15
From: Pacific Northwest
Maybe the service manual should read "38 oz. (or there about)"?
All I know is that 38 oz. always fills the primary to the recommended level....every time.
I do understand what you're saying - 35 oz. isn't going to destroy everything in the primary.
Ultimate HDF Member
Joined: Feb 2010
Posts: 8,039
Likes: 1,305
From: Jayhawk Country
Why would you take the chance, just put in the 38 oz. per the manual. The guys that are saying less than that is enough will be no where around when your primary is toast. This is the internet, don't believe everything you read here. But you can believe your manual.