Slow start
Seasoned HDF Member
Joined: Mar 2021
Posts: 17,928
Likes: 3,563
From: backwoods
Basicly, His HD dealer told him to go with a thinner oil, as the cold temps + thick oil could potentially make it hard to start, and I believe there is some truth to that, but I would think you would probably need to be in the "below freezing" temps with dino oil for that to happen, my big old hog turns right over with my little 16 cell lithium battery, and el cheapo Supertech 20w50 oil.
As for rotella I run it in the tractor, just cause the diesel guys love that stuff. But I got over 300k miles on my gasser.
Last edited by Rounders; Dec 5, 2024 at 07:23 PM.
Seasoned HDF Member
Joined: Mar 2021
Posts: 17,928
Likes: 3,563
From: backwoods
Do a google search, I am sure you will find threads and hot debates about people running diesel in harley. Of course like all oil threads, it gets heated,
Seasoned HDF Member
Joined: May 2018
Posts: 5,814
Likes: 7,142
From: Las Vegas
Harley manuals used to say to use diesel if you could not get harley branded oil. This was for TCs, I am sure they said it for evos too. The theory was more detergents in diesel oil or such,
Do a google search, I am sure you will find threads and hot debates about people running diesel in harley. Of course like all oil threads, it gets heated,
Do a google search, I am sure you will find threads and hot debates about people running diesel in harley. Of course like all oil threads, it gets heated,
Newbie Numb Nuts with all of the participation trophies from several earlier posts in this thread is sure to have a stroke when he discovers he's wrong, but he won't admit it.
Seasoned HDF Member
Joined: Aug 2006
Posts: 24,428
Likes: 30,651
From: Pennsylvania
Oh Boy a battery/starting thread turned into an oil thread.
Best of both worlds.
I have no input for the OP other than what has already been provided, so I'll sit by and be entertained.
NOTE:
The above information, while credible, is worth what you paid for it and should not be considered gospel.
Do due diligence, research and have a H-D Field Service Manual before working on your bike.
You will probably have many opinions and suggestions presented; make sure you research the person providing the helpful information as there are some who provide good information that is useful and some who speak out of other orifices with gibberish. You will figure out this quickly.
Best of both worlds.
I have no input for the OP other than what has already been provided, so I'll sit by and be entertained.
NOTE:
The above information, while credible, is worth what you paid for it and should not be considered gospel.
Do due diligence, research and have a H-D Field Service Manual before working on your bike.
You will probably have many opinions and suggestions presented; make sure you research the person providing the helpful information as there are some who provide good information that is useful and some who speak out of other orifices with gibberish. You will figure out this quickly.
Seasoned HDF Member
Joined: Mar 2006
Posts: 10,017
Likes: 14,663
From: From the Burgh to the turd of N.E. OH
Road Warrior
Joined: Dec 2012
Posts: 1,539
Likes: 692
From: magnolia tx
I don't even know why I'm writing this, the last thing I wanna do is get in on an oil thread on here
lol, but here goes, I'm not personally married to any brand of oil but to give Amsoil credit it did rank pretty high on the YouTube on a channel called Project Farm, this guy test everything ten ways to Sunday and he seems to know what he is doing but If I remember correctly old Pennzoil also ranked close to the top, so
, 
lol, but here goes, I'm not personally married to any brand of oil but to give Amsoil credit it did rank pretty high on the YouTube on a channel called Project Farm, this guy test everything ten ways to Sunday and he seems to know what he is doing but If I remember correctly old Pennzoil also ranked close to the top, so,
Last edited by mike131; Dec 6, 2024 at 07:41 AM.
Seasoned HDF Member
Joined: May 2008
Posts: 21,032
Likes: 12,560
From: South Carolina
Seasoned HDF Member
Joined: Jan 2011
Posts: 157,332
Likes: 56,890
From: Michigan 15 Minutes East Of Hell
Hey genius ... I referenced the highlighted reply ... Of course you and your infinite knowledge took offense that someone ( me ) pointed that out ... Be careful stepping up on your podium ... You might ( probably will ) fall down ... BTW welcome to the Forum and have a Snickers
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Tourer
Joined: Aug 2022
Posts: 285
Likes: 217
From: NH
I was going to suggest to the OP to disconnect and reconnect the fuel line. When I changed my battery earlier this year the bike slow cranked. I thought WTF and posted the issue here. One person suggested checking the fuel line quick disconnect right below the tank. I disconnected and reconnected it and that solved the slow crank. I know the OP said it's been a month since the new battery, but the fuel line quick disconnect is a relatively easy thing to do. At least it will cross one thing off the list before throwing parts at it.
Okay, back to an oil thread... Can I run 0W-20? My Chevy truck and TSX both run it. (Just kidding!).
Okay, back to an oil thread... Can I run 0W-20? My Chevy truck and TSX both run it. (Just kidding!).
Road Warrior
Joined: Aug 2020
Posts: 1,277
Likes: 2,079
From: NC
To the OP, being that your dealer gave you the "thumbs up" on going with a thinner oil (to correct my choice of words when I responded to Rounders), what are you running in your primary (not interested in the brand)? if you are running a heavy gear oil, that could also be a problem if it is the cold temps that is effecting start up.