Primary oil .
Primary oil .
A quick question . Why all the drama about oil levels in the primary case when you do a complete oil change ? It takes exactly a quart , so why not just pour in a quart and be done with it . You don't even have to remove the Derby cover because it can easily poured in through the chain inspection cover .Am I missing something here ? As a footnote , I wonder why HD couldn't just put a sight glass in the primary cover so that I don't have to remove my foot peg once a month .
Last edited by Midpegs; May 20, 2019 at 04:50 AM.
Road Master
Joined: Sep 2016
Posts: 1,048
Likes: 492
From: Heart of Georgia
Newer bikes don’t have inspection covers and they don’t all hold exactly one quart. My 17 Heritage holds 36 ounces, which works out good since the trans takes 28 ounces. I put 28 in the trans, then pour a full qt. plus the leftover 4 ounces into the primary. Works great as long as I use the same lube in both trans and primary.
Seasoned HDF Member
Joined: Aug 2006
Posts: 24,492
Likes: 30,781
From: Pennsylvania
Newer bikes dont have inspection covers and they dont all hold exactly one quart. My 17 Heritage holds 36 ounces, which works out good since the trans takes 28 ounces. I put 28 in the trans, then pour a full qt. plus the leftover 4 ounces into the primary. Works great as long as I use the same lube in both trans and primary.
Stellar HDF Member
Joined: May 2007
Posts: 3,256
Likes: 522
From: USA
For the OP, post 5 sums it up.
Many do as you've written...pour 1 qt through primary chain inspection hole.
The debate?
Maybe because the service guide does not offer that re-fill procedure as an option?
Without HD "blessing" we default to the remove derby cover procedure.
Is there a benefit to removing the derby?
I don't think so.
Most of he clutch or gears are not visible, a few dollars for O-rings is extra cost, possibility of a clutch adjustment error and torx derby screws damage.
I really don't see a benefit other than viewing the exact level of re-filled oil in the case.
Many do as you've written...pour 1 qt through primary chain inspection hole.
The debate?
Maybe because the service guide does not offer that re-fill procedure as an option?
Without HD "blessing" we default to the remove derby cover procedure.
Is there a benefit to removing the derby?
I don't think so.
Most of he clutch or gears are not visible, a few dollars for O-rings is extra cost, possibility of a clutch adjustment error and torx derby screws damage.
I really don't see a benefit other than viewing the exact level of re-filled oil in the case.
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HDF Community Team
Joined: Dec 2011
Posts: 8,547
Likes: 3,974
From: San Diego, CA
No, some people are just ****, and think an extra ounce splashing around will destroy their transmission. Same people that use a torque wrench on the tiniest of bolts, or need a gear shift light to tell them when to change gears.. Or, a low fuel light to tell them not to run out of gas.
John
John
Last edited by John Harper; May 20, 2019 at 12:17 PM.
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Road Warrior
Joined: Feb 2007
Posts: 1,625
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From: The Biggest Little City, Reno, NV
No, some people are just ****, and think an extra ounce splashing around will destroy their transmission. Same people that use a torque wrench on the tiniest of bolts, or need a gear shift light to tell them when to change gears.. Or, a low fuel light to tell them not to run out of gas.
John
John
Thanks !
Thanks everyone . Seems like common sense prevails . I've owned and worked on my bikes for 40 years but this is my first Harley so I guess there is a tendency to do things by the book at first . The thing is though , the main purpose of the book seems to be to encourage the owner to have all their servicing done by a Harley dealership. So it's a quart out and a quart in , simple. Any book that contains 80+ warnings about things that could result in serious injury or death probably shouldn't be taken too seriously . 😀