Optimal oil Temp?
Club Member
Joined: Feb 2007
Posts: 16,320
Likes: 306
From: Boynton Beach, FloriDuh
Every time you ride your bike and it's subjected to a heat-up / cool-down cycle, moisture can and will form in the oil system, assuming your in something other than a 0% humidity environment.
Remembering that water boils at 210*F, the only way to rid the oil of the moisture is for it to reach that 210* temp. No, that doesn't mean your dipstick temp gauge needs to reach 210*, because as the hot oil is returned to the tank and mixed with the somewhat cooler tank oil and the temperature will drop.
In approx. numbers, you want to see at least 180* for the tank temp. in order to ensure that it's getting hot enough to boil off the moisture.
This is the same reason that it's never a good idea to occasionally fire-up a stored bike in the winter. You'll get it just hot enough to cause moisture to condense in the oil system, but not hot enough, long enough, to boil it off.
Remembering that water boils at 210*F, the only way to rid the oil of the moisture is for it to reach that 210* temp. No, that doesn't mean your dipstick temp gauge needs to reach 210*, because as the hot oil is returned to the tank and mixed with the somewhat cooler tank oil and the temperature will drop.
In approx. numbers, you want to see at least 180* for the tank temp. in order to ensure that it's getting hot enough to boil off the moisture.
This is the same reason that it's never a good idea to occasionally fire-up a stored bike in the winter. You'll get it just hot enough to cause moisture to condense in the oil system, but not hot enough, long enough, to boil it off.
Account Deactivated
Joined: Oct 2009
Posts: 1,757
Likes: 8
From: Central Florida
It boils at 212 at sea level,,
I would think at best those analog guages are +-10% at best
I would also bet yer guage tells you the boiling water Is about
160 degree's,,,,,,,
Just sayin,
Road Warrior
Joined: Oct 2007
Posts: 1,599
Likes: 11
From: Colonial Beach, Virginia
cHarley, When I park my truck I always park it so I won't have to move it for someone to get out of my driveway. As you said that is hard on the oil and really hard on the battery.
My bike and truck are lucky that way, I live 35 miles from every where.
My bike and truck are lucky that way, I live 35 miles from every where.
Last edited by 1200Cdriver; May 26, 2011 at 03:03 PM. Reason: Spelling
Club Member
Joined: Feb 2007
Posts: 16,320
Likes: 306
From: Boynton Beach, FloriDuh
But whether is fossil or synthetic, you need the same temp to boil off the moisture.
Stellar HDF Member
Joined: Aug 2009
Posts: 3,212
Likes: 212
2002 XLH883 here, running M1 V-Twin. I have the analog temp. oil dipstick and here are what I hit as far as temps go.
Ambient air: oil temps all in degrees F
40-50: 150-155
50-60: 155-165
60-70: 165-180
70-80: 180-195
80-85: 200-215
85-90: 215-230
It's never been over 215 for me, so above that is extrapolation, but it is fairly accurate. This fully warmed up, 75-25% highway-city riding.
Ambient air: oil temps all in degrees F
40-50: 150-155
50-60: 155-165
60-70: 165-180
70-80: 180-195
80-85: 200-215
85-90: 215-230
It's never been over 215 for me, so above that is extrapolation, but it is fairly accurate. This fully warmed up, 75-25% highway-city riding.
Road Captain
Joined: Aug 2010
Posts: 739
Likes: 12
From: Ontario, New York
Rode mine for about 90 miles today with the outside temperature at 91 degrees.Oil dipstick with temp.gauge read about 210-220 degrees.
HD Forum Stories
The Best of Harley-Davidson for Lifelong Riders
6 Weirdest Harley-Davidsons Ever Sold to the Public
Verdad Gallardo
7 Times Harley-Davidson Chucked Tradition Out the Window
Verdad Gallardo
7 Surprising Harley-Davidson Products that Are Not Motorcycles
Verdad Gallardo
8 Best Harley-Davidson Motorcycles Ever
Pouria Savadkouei
10 Worst Harley-Davidson Motorcycles Ever
Pouria Savadkouei
Killer Custom's Jail Break Is The Breakout That Refused to Blend In
Verdad Gallardo
Crazy Bunderbike Build Looks Amazing, But Is It Impossible to Ride?
Verdad Gallardo
Harley-Davidson Reveals Super Cool Cafe Racer Concept
Verdad Gallardo
Engraved Rebellion: Inside Bundnerbike's Glam Rock II
Verdad Gallardo
Club Member
Joined: Jun 2007
Posts: 45,429
Likes: 2,898
From: Bedford UK
Let us be clear that bike gauges like voltmeters, oil temp and pressure gauges are not very accurate. Best not to look at them, frankly! My favourite indy calls them 'worry gauges'. Ride and enjoy - your bike will be fine in all but the very most extreme conditions, when most of us will not go riding.
Road Master
Joined: Apr 2012
Posts: 1,188
Likes: 24
From: New Hampshire
Oil temp is kind of dependent on the air temperature as warmer air will not cool the engine as much. it's been in the 80-90 degree range here and i see oil temps up to 220 on the hottest days.