ATF in a Harley primary ?

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Aug 11, 2011
While researching Harley primary chain case oils I discovered quite a few Harley guys are using ATF in they're primary chain cases. I was all set to use the Harley brand of primary oil but the favorable posts concerning ATF in the primary got me to thinking....LOL! Theres a sticky section on the VTwin forum I frequent about using it and alot of guys use it and swear it's the oil to use in a Harley primary chain case. It seems the consensus is to use the Dexron/Mercon flavor but a number of guys like the Ford F and the Chrysler atf plus4 as well. It seems the Dexron/Mercon gives a smoother engagement as opposed to the Ford or Chrysler which engages the clutch more aggressively for drag bikes or for a more aggressive type of riding. Does anyone here have experience or opinions on using ATF in a Harley primary chain case? Thanks
Type F is free of most friction modifiers. It'll give you one heck of an engagement alright. Just busted open 2 cases of Amsoil Super Shift, which is their synthetic Type F spec. Very nice.
I use Rotella 15w40 in mine bikes also.
I did use B&M Trick Shift (not the syn type) in the primary and liked it.
I thought I had a better clutch feel and hook up with the Trick shift.
But you have to lubricate the compensator and for that reason I went with Rotella. First think I noticed was less fuzz on the drain plug magnet and the clutch feel was about the same. And a lot less primary noise.
There are folks in the GM truck world that decide to eschew ATF in their t-case and use motor oil instead, based upon a SWAG suggestion by a supposed guru.

Ironic, is it not, that some H/D folks will try ATF instead of what is essentially a motor oil, and GM truck guys will try motor oil instead of ATF. Both the H/D primary and the GM t-case are high-torque environments with chain-driven gears.

The grass is always greener on the other side of the drain plug ...
I've never used ATF in any of my primary's. I personally don't believe it's the proper fluid for the job. I don't use any of Harley's oil products as I feel they are overpriced for what they are. But I do use oils that are closer to what they recommend. On the other sites I visit there are guys that say it works great, as well as those that say it works great for a while, then shifting gets notchy. One commented that while it's main purpose is to cool the clutch pack, it has to lube the chain and sprockets. Another said it can cause the magnets in the stator to become loose of fall off. I can't say I've seen anyone with that problem. I feel there are better choices then ATF for a Harley primary. If it was cheaper and worked just as good, the factory would recommend it. They would sell it and make a fortune.,,
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