Formula Plus in primany
Outstanding HDF Member
Joined: Dec 2008
Posts: 2,007
Likes: 353
From: Ohio
Nobody that I know of has done the amount of R&D that the MOCO has for their bikes. Nobody. So I see no reason to disagree with them on their lube recommendations. Is it all that critical? I don't think so. Formula + works just fine. Would just plain 30W work too? Probably. And in a pinch I would use it. Are there better products out there than what HD supplies? Maybe. Maybe not. Who is the authority that decides? I'll just stick with HD.
Grand HDF Member
Joined: Dec 2007
Posts: 4,999
Likes: 55
From: Bay Area
Been using Formula+ for almost 50k miles. I tried redline primary and it clunked harder when going into gear especially when hot that the F+ did. I was running 110 hp back then now Im at 124 and Im going to stay with the F+. I spoke to seasoned indys and they all agreed that F+ is excellent to use, so Im staying with it.
It is very important to change primary fluid often as the clutch material will degrade the oil, more so if youre a local bar hopper when all you do is stop n go riding.
It is very important to change primary fluid often as the clutch material will degrade the oil, more so if youre a local bar hopper when all you do is stop n go riding.
Seasoned HDF Member
Joined: Sep 2008
Posts: 14,146
Likes: 11,220
From: San Diego, CA
I remember when Syn3 first came out. The marketing hype was all about "Same oil in all three holes". They really wanted to boost the Syn3 sales and apparently figured we were too simple to keep track of 3 different types of lubricant.
Well, I tried it, during a service on my Heritage. Before my next service, I switched out the tranny and primary the proper fluids.
Been using Formula + in the primary and synthetic gear oil in the tranny (currently mobil 1) since I've been doing my own services for many years. No problems...
Well, I tried it, during a service on my Heritage. Before my next service, I switched out the tranny and primary the proper fluids.
Been using Formula + in the primary and synthetic gear oil in the tranny (currently mobil 1) since I've been doing my own services for many years. No problems...
Grand HDF Member
Joined: Nov 2013
Posts: 3,807
Likes: 1,488
From: SW Washington State
Nobody that I know of has done the amount of R&D that the MOCO has for their bikes. Nobody. So I see no reason to disagree with them on their lube recommendations. Is it all that critical? I don't think so. Formula + works just fine. Would just plain 30W work too? Probably. And in a pinch I would use it. Are there better products out there than what HD supplies? Maybe. Maybe not. Who is the authority that decides? I'll just stick with HD.
Road Warrior
Joined: Jul 2009
Posts: 1,979
Likes: 2
From: Northern Colorado
As far as the primary chaincase is concerned, Formula+ works just as good as anything else people are using, and since that's what was in there when it left the factory, I see no reason to use something different.
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Road Warrior
Joined: Mar 2009
Posts: 1,485
Likes: 232
From: Ohio
Nobody that I know of has done the amount of R&D that the MOCO has for their bikes. Nobody. So I see no reason to disagree with them on their lube recommendations. Is it all that critical? I don't think so. Formula + works just fine. Would just plain 30W work too? Probably. And in a pinch I would use it. Are there better products out there than what HD supplies? Maybe. Maybe not. Who is the authority that decides? I'll just stick with HD.
Seasoned HDF Member
Joined: Sep 2013
Posts: 6,175
Likes: 1,966
From: Great State of Canada
1) Seals; I expect this is a non-issue with synthetics these days but since I was E-mailing anyway,,,.
2) Condensation; in my part of the world this issue is real and I understand ester based oils are prone to hydrolysis and acid formation in the presence of water. Again, as versatility is a characteristic with ester formulations I expect RL has dealt with this but I'm interested in what they have to say.