ATF Fluid
Cruiser
Joined: Feb 2007
Posts: 138
Likes: 5
From: Dublin, Ireland.
Just a question about ATF in primary.
How can it improve gear change when it is in the primary, surely it is the gear box oil that would make a difference, smoother changing, less clunking etc etc. Am I missing something?
TC
How can it improve gear change when it is in the primary, surely it is the gear box oil that would make a difference, smoother changing, less clunking etc etc. Am I missing something?
TC
Elite HDF Member
Joined: Sep 2007
Posts: 4,468
Likes: 12
From: Bluffton, South Carolina
It has to do with the viscosity, additives, etc and how it works with the clutch. If the clutch is dragging slightly, neutral can be hard to find and it will "clunk" when you put it in gear.
Intermediate
Joined: Oct 2010
Posts: 41
Likes: 0
From: Washington state
Doug-I had a very slow leak that would only show a few drops if my bike sat for a week. When I went to ATF I would have a small puddle within a short time. I couldn't handle that bad of a leak, so my hand was forced. Turned out to be leaking from the bottom bolt of my chain adjuster . It was an easy fix (loctite on bolt) and one I wanted to do anyway.
Ultimate HDF Member
Joined: Jun 2007
Posts: 9,193
Likes: 494
From: Richmond, VA
Yes, just like MIACYCES said. When your clutch works better you can bet your tranny shifts smoother.
Cruiser
Joined: Feb 2007
Posts: 138
Likes: 5
From: Dublin, Ireland.
Thanks people, I was missing something.
As I am changing my primary oil, which is best oil to use?
I got a new transmission plug in my local Harley dealer and they said they use Harley primary oil which is syntetic and would reccomend that.
But for an old evo (1986) which is best?
Thanks
TC
As I am changing my primary oil, which is best oil to use?
I got a new transmission plug in my local Harley dealer and they said they use Harley primary oil which is syntetic and would reccomend that.
But for an old evo (1986) which is best?
Thanks
TC
Seasoned HDF Member
Joined: Aug 2007
Posts: 8,198
Likes: 3,087
From: NW AR
"Which is best" is the whole issue, and subject to much, much debate. Ask 20 of us "which is best" and you'll get 23 answers. HD doesn't make primary oil anymore. I personally have had excellent results with Mobil 1 ATF.
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Seasoned HDF Member
Joined: May 2008
Posts: 21,132
Likes: 12,693
From: South Carolina
Same here, I use Mercon v because it is the same fluid for my car and truck. One less special lube to keep on the shelf, and no chance of dumping the wrong ATF into the car/truck (I`m gettin old).