primary lubrication
Road Master
Joined: Jul 2008
Posts: 1,142
Likes: 7
From: Michigan
anytime i've asked a question regarding what oil guys are using in the primary, the answer i get most often is "any dino oil". I am sure that synthetic will work, just don't think there is any reason to spend extra money for synthetic, the value just isn't there as far as any improvements in how it performs compared to the $3/quart 20w50
Road Master
Joined: Feb 2006
Posts: 897
Likes: 0
From: South-Central Minnesota
The thing I've always been told to avoid is any oil with friction modifiers in it like molybedenum, which can contribute to clutch slipping. Most light weight car oils use friction modifiers to meet energy saving requirements. I believe everything below 50 weight is required to contain some friction modifiers.
For the past several years, I've been happily using ATF [automatic transmission fluid] type F. I first got the idea from several others on harley-tech-talk already using the practice. If you think about it, it makes perfect sense. The oil in the primary's main job is to clean the clutch pack and lubricate the primary chain. Any oil will keep the chain clean, but ATF is designed for wet clutch use and will not contribute to clutch slipping. On top of it all, it is usually cheaper than motor oil.
In my opinion, ANY synthetic used in the primary is major overkill and a waste of money. I save the good stuff for the motor and tranny.
For the past several years, I've been happily using ATF [automatic transmission fluid] type F. I first got the idea from several others on harley-tech-talk already using the practice. If you think about it, it makes perfect sense. The oil in the primary's main job is to clean the clutch pack and lubricate the primary chain. Any oil will keep the chain clean, but ATF is designed for wet clutch use and will not contribute to clutch slipping. On top of it all, it is usually cheaper than motor oil.
In my opinion, ANY synthetic used in the primary is major overkill and a waste of money. I save the good stuff for the motor and tranny.
Road Warrior
Joined: Aug 2006
Posts: 1,440
Likes: 0
From: Columbus,Indiana/ Arecibo,Puerto Rico
I've been using Mobil 1 for the past 25,000 miles. I change it every 5k. I've never had to adjust the clutch yet! Maybe it works.
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Road Master
Joined: Feb 2006
Posts: 897
Likes: 0
From: South-Central Minnesota
To you and Dwyer...we are talking about primary chain case lubrication here...While gear lube may work, it is serious overkill and much heavier than whats called for.
I run Redline heavy shock-proof gear lube in the TRANNY which is very heavy oil...like 80-250w or something.