HD Fan assisted oil cooler kit for M8 engines
So I had a fair amount of work done on my 18 Road Glide Ultra and one component was the oil cooler. Dealer told me it doesn’t fit the 18 Road Glide Ultra. They refunded the part price of course. This sound right? My dealer has made a few mistakes on what fits and what doesn’t so just confirming (traveling and don’t have parts catalog in front of me).
Cruiser
Joined: Mar 2017
Posts: 147
Likes: 18
From: NW FL
Road Master
Joined: Sep 2011
Posts: 1,033
Likes: 41
From: Mount Airy, North Carolina
For the benefit of others, if you live in a traffic clogged state like Florida, an oil cooler will be of some help keeping oil cooler in traffic. Its not the heat in Florida its the traffic as other states are much hotter in the summer such as mine here is SC.
The reason most bike makers do not include a fan is the faster you go, the hotter your oil gets, not the other way around.
So if your traveling (like we do) on the interstates. 2up at a true 80 MPH, when massive amounts of air are blowing through the cooler, far more then any fan can deliver, that is when your oil is the hottest, once you slow down, to normal stop and go traffic, you oil cools down rapidly all with no fan.
The reason your oil is hottest at the highest possible speeds, again with massive amounts of air blowing through the cooler is simple. The engine is designed to spray oil on the bottom of the pistons at high speeds to cool the pistons down, this is what heats up the oil and why no fan, at low speeds they are no longer effectively sprayed and your oil cools down all by itself.
If your worried about stopped in traffic you are FAR better off with a fan that blows on the heads of the engine, more then any cooler fan. Lenale and Love Jugs.
I have the Lenal and like it because it looks a hell of a lot nicer then the horn, max cooling will come from love juggs though. An oil cooler is not going to help cool the heads of the engine.
Oh and while we are at it, most do not know the normal operating temperature of the oil as stated in the Shop Manual.
The normal operating temperature of the oil is listed as 230 degrees.
For those of you with a PROPER oil temperature guage, travel at 80 MPH for 30 minutes or longer on a almost 100 degree day, as soon as possible stop the bike and measure oil temperature. You will find it around 250 to 260 degrees, then ride around town, you will see it drop 20 degrees, all without a fan.
If you have a water cooled bike, adding a fan is a waste as the fan on the radiators will keep the engine cool which will keep the oil cool.
If you dont have a water cooled fan and are worried about stuck in traffic overheating, then get an engine fan, not an oil cooler fan.
The reason most bike makers do not include a fan is the faster you go, the hotter your oil gets, not the other way around.
So if your traveling (like we do) on the interstates. 2up at a true 80 MPH, when massive amounts of air are blowing through the cooler, far more then any fan can deliver, that is when your oil is the hottest, once you slow down, to normal stop and go traffic, you oil cools down rapidly all with no fan.
The reason your oil is hottest at the highest possible speeds, again with massive amounts of air blowing through the cooler is simple. The engine is designed to spray oil on the bottom of the pistons at high speeds to cool the pistons down, this is what heats up the oil and why no fan, at low speeds they are no longer effectively sprayed and your oil cools down all by itself.
If your worried about stopped in traffic you are FAR better off with a fan that blows on the heads of the engine, more then any cooler fan. Lenale and Love Jugs.
I have the Lenal and like it because it looks a hell of a lot nicer then the horn, max cooling will come from love juggs though. An oil cooler is not going to help cool the heads of the engine.
Oh and while we are at it, most do not know the normal operating temperature of the oil as stated in the Shop Manual.
The normal operating temperature of the oil is listed as 230 degrees.
For those of you with a PROPER oil temperature guage, travel at 80 MPH for 30 minutes or longer on a almost 100 degree day, as soon as possible stop the bike and measure oil temperature. You will find it around 250 to 260 degrees, then ride around town, you will see it drop 20 degrees, all without a fan.
If you have a water cooled bike, adding a fan is a waste as the fan on the radiators will keep the engine cool which will keep the oil cool.
If you dont have a water cooled fan and are worried about stuck in traffic overheating, then get an engine fan, not an oil cooler fan.
Road Warrior
Joined: Jul 2007
Posts: 1,462
Likes: 22
From: Delaware
Stellar HDF Member
Joined: Sep 2009
Posts: 3,351
Likes: 1,936
From: Formerly Tampa Bay, FL, Currently Western PA
Interesting, then again, I do not have an M8.
I am curious what your temperature is while you are riding, interstate speeds 80MPH 1/2 hour or more. Do you run at those speeds, if so, do you ever check the temperature while you are moving?
Also how are you getting your oil temperature readings?
BTW - I am fully in the camp that says there is nothing wrong and only good with a fan on the oil cooler as I am also in the camp that says an engine fan is also a good thing.
Also, 230 degrees is normal operating temperature on the Rushmore Bikes, maybe on the M8s too.
I am curious what your temperature is while you are riding, interstate speeds 80MPH 1/2 hour or more. Do you run at those speeds, if so, do you ever check the temperature while you are moving?
Also how are you getting your oil temperature readings?
BTW - I am fully in the camp that says there is nothing wrong and only good with a fan on the oil cooler as I am also in the camp that says an engine fan is also a good thing.
Also, 230 degrees is normal operating temperature on the Rushmore Bikes, maybe on the M8s too.
Road Captain
Joined: Jan 2015
Posts: 626
Likes: 109
From: New York
What engine or oil temp does the fan kick on at?
I know this thread is a little dated. However, has anyone found out at what temperature the Fan assisted oil cooler kicks on? Previously using Thundermax on my 2018 RGS, the fan would come on all the time; even when I would turn the pike of and lean it on the side stand. Ive since gone back to the stock ECM and flash Tuned with Techno Research Direct Link. The bike definitely runs cooler now, but it has been really hot this summer and I have not heard the fan come on at all. I know the fan works because when I test by opening the throttle fully when the ignition switch is on and the engine is off, I can hear the fan come on. Just really curious about what engine or oil temperature the fan is activated at. The fan was is enabled through the Techno Research software, so I know that was done correctly... Any response would be greatly appreciated.
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Intermediate
Joined: Feb 2018
Posts: 31
Likes: 6
From: North Carolina
H-D Fan assisted oil cooler
Anyone using this HD kit? Is it worth doing?
https://www.harley-davidson.com/stor...oil-cooler-kit
https://www.harley-davidson.com/stor...oil-cooler-kit
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