20w50 or straight 50w
Grand HDF Member
Joined: Dec 2007
Posts: 4,999
Likes: 55
From: Bay Area
Road Warrior
Joined: May 2008
Posts: 1,513
Likes: 6
From: SC
Not so, single weight oils can be used with no issues in newer engines. Im running Amsoil Synthetic 60wt motorcycle oil in my 117" for the last 2 summers. I see my engine oil temps stay at 195-210 in 100 degree weather riding my trike. It also keeps the valvetrain quieter.
With the gas now having 10% enthonol and the goverment possibly mandating a change to 15% our engine will run hotter in the summer months
I switch to 20/60w Redline for winter riding for the additives in the multi weight oil to keep the oil fluid viscosity for cold weather start ups
Amsoil website >> http://www.amsoil.com/storefront/mcs.aspx
Last edited by FLTR2008TRIKE; Jul 9, 2011 at 04:48 PM.
Club Member
Joined: Mar 2009
Posts: 66,125
Likes: 51,440
From: Niles Canyon Ca.
Because of the way Evo and later engines are designed and the gaskets used running a heavy weight oil is a very bad idea it will run fine but blow gasket like a crack ***** after a pipe . Older bikes like shovels and pans need it but have much higher bolt torques on the upper ends , evo's and later are about half the torque specs and rely on the engine heating and expanding to seal everything also why everything says warm the bike fully BEFORE riding . Cold engine with cold thick oil will blow by gaskets that's why evos had so many problems years ago with guys coming off shovels and new haven't got a clue new bike owners hitting the button and gone with no warm up , you can't run them the same way .
Road Warrior
Joined: May 2008
Posts: 1,513
Likes: 6
From: SC
20k miles using 60wt and not a gasket leak as of yet. Gaskets for Evos are not the same as the new gaskets Harley is using on the Twin Cams. 3 piece Evo rocker boxes had issues leaking if you didnt get the middle and top cover aligned correctly. We all know the base gaskets on a Evo didnt seal until the engine temps were up to sweal the aluminum for sealing ( Hard riding while the engine was still cool caused cyclinder gaskets to blow out ) HD did come up with O rings for the cylinders with the Twin Cams for better sealing.
Internal oil pump in a cam chest on a Twin Cam with a o-ring reduced the chance of the oil pump leaking externally like a Evo as well.
Internal oil pump in a cam chest on a Twin Cam with a o-ring reduced the chance of the oil pump leaking externally like a Evo as well.
Road Captain
Joined: Mar 2011
Posts: 559
Likes: 5
From: Tampa Bay, Florida
I'm new the twin cam motors, this 2010 being my first. I’m planning on 20W-50 all year long.
On my last Harley, a 1986 Evo, I ran 60w in the summer and 20W-50 in the winter. Never had a engine related problem.
I've always used Harley oil.
On my last Harley, a 1986 Evo, I ran 60w in the summer and 20W-50 in the winter. Never had a engine related problem.
I've always used Harley oil.
Grand HDF Member
Joined: Mar 2007
Posts: 4,928
Likes: 285
From: Edmond Oklahoma
50w strait- 60 degrees F or above.
60w strait - 80 degrees F or above.
The disadvantage of multigrade oil is that it doesn't hold the max viscosity at temperature as long as strait grade viscosity. Thats OK with big changes of temperature like most of the year, but the lows in Oklahoma right now are in the 80s, and the highs between 100 and 110F. According to Harley, I can safely use a strait weight oil of ........
What are the lows in Michigan?
The smaller the differences in multi weight oils, the better because they tend to hold max viscosity longer. That means a 20w-50w is better than a 15w-50w oil because it will hold the high side longer. 30 w-50w is even better and 50w strait is best. Provided the ambient temps allow.
Beary
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Well... Read a ton of articles and honestly couldn't find one article that said mixing single/multi grade oils a no-no. I found a few articles advising against mixing syn/dino oil so wonder how old those were?? That said, I really doubt the 50w VR1 will pose any problems with the 15w-50 syn on a 3k mile/85+ temp highway ride. It will be changed out to VR1 20w-50 upon my return. Gotta love oil topics .....
How, exactly, does oil work on the molecule level, and how do the oil molecules fight each other?