M8 Engine Temps
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Joined: Jan 2013
Posts: 68
Likes: 13
From: Illinois
Road Warrior
Joined: Nov 2022
Posts: 1,541
Likes: 543
From: MN
sorry if I offended thee, I just have always found it amusing how much fussing and fretting and how fickle Harley owners can be is all .. and yes, forum topics are for differing opinions from all .. like Point Counterpoint
https://www.youtube.com/watch?v=c91XUyg9iWM
https://www.youtube.com/watch?v=c91XUyg9iWM
Road Warrior
Joined: Nov 2022
Posts: 1,541
Likes: 543
From: MN
First engine bulk oil temp measurement I got was today (too humid yesterday to ride for me): 200 degrees F via dipstick thermometer. Wow, cool.
References:
Average truck engine oil bulk temp readout on EVIC is 220 degrees F.
Average Onan flathead air-cooled cylinder head temperature @ 1/2 load in 85F measured 330 degrees F (with full-time flywheel cooling fan)
Average Onan OHV air-cooled cylinder head temperature @ 1/2 load in 85F measured 270 degrees F (with full-time flywheel cooling fan)
Today's Ride Conditions:
Ambient air: 77 degrees F
Mileage: 24 mile trip (temp reading post-trip)
Route: mix of stop and go city, suburban access roads, rural highways.
Engine: '21 Heritage Classic M8 107, oil-cooled heads thru air cooler radiator
Love Jug Cylinder Head Fans: On
Thermometer: Pazoma Oil Dipstick Thermometer with analogue dial readout
I will be testing more this week with hotter ambient temps, with fans on and off, will report results.
References:
Average truck engine oil bulk temp readout on EVIC is 220 degrees F.
Average Onan flathead air-cooled cylinder head temperature @ 1/2 load in 85F measured 330 degrees F (with full-time flywheel cooling fan)
Average Onan OHV air-cooled cylinder head temperature @ 1/2 load in 85F measured 270 degrees F (with full-time flywheel cooling fan)
Today's Ride Conditions:
Ambient air: 77 degrees F
Mileage: 24 mile trip (temp reading post-trip)
Route: mix of stop and go city, suburban access roads, rural highways.
Engine: '21 Heritage Classic M8 107, oil-cooled heads thru air cooler radiator
Love Jug Cylinder Head Fans: On
Thermometer: Pazoma Oil Dipstick Thermometer with analogue dial readout
I will be testing more this week with hotter ambient temps, with fans on and off, will report results.
Seasoned HDF Member
Joined: Jan 2008
Posts: 13,674
Likes: 11,461
From: State of Confusion
who's "arguing"? .. as I mentioned, I always just find it a bit amusing and entertaining is all ..... anyway, if it makes you feel better then by all means it's worth fussing over
Didn't have any way to monitor engine temps, but was stuck in bumper to bumper traffic from Chicago to Indianapolis a couple weeks ago when it was 96 degrees plus and was seriously impressed with the lack of heat coming from my oil cooled M8. My T/C's would have roasted my nutz off.
Road Warrior
Joined: Nov 2022
Posts: 1,541
Likes: 543
From: MN
keep it going - it entertains you, apparently.
Road Warrior
Joined: Nov 2022
Posts: 1,541
Likes: 543
From: MN
Didn't have any way to monitor engine temps, but was stuck in bumper to bumper traffic from Chicago to Indianapolis a couple weeks ago when it was 96 degrees plus and was seriously impressed with the lack of heat coming from my oil cooled M8. My T/C's would have roasted my nutz off.
Do you have catted mufflers? Those suckers get hot, but the engine doesn't heat my legs too much.
I noticed this summer the EITMS system has only come on once this summer with cooing fans installed, compared to multiple times last summer without cooling fans. This summer so far has 24 days of 90+ F compared to 20 days last summer and 13 day summer average. And more 90F days coming this week. I don't know what rear head temp setting the EITMS comes on at. Have also read the system doesn't do a lot to keep engine temp down. II left it on, doesn't seem to hurt anything.
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Stellar HDF Member
Joined: Apr 2012
Posts: 3,117
Likes: 1,193
From: Maryland
First engine bulk oil temp measurement I got was today (too humid yesterday to ride for me): 200 degrees F via dipstick thermometer. Wow, cool.
References:
Average truck engine oil bulk temp readout on EVIC is 220 degrees F.
Average Onan flathead air-cooled cylinder head temperature @ 1/2 load in 85F measured 330 degrees F (with full-time flywheel cooling fan)
Average Onan OHV air-cooled cylinder head temperature @ 1/2 load in 85F measured 270 degrees F (with full-time flywheel cooling fan)
Today's Ride Conditions:
Ambient air: 77 degrees F
Mileage: 24 mile trip (temp reading post-trip)
Route: mix of stop and go city, suburban access roads, rural highways.
Engine: '21 Heritage Classic M8 107, oil-cooled heads thru air cooler radiator
Love Jug Cylinder Head Fans: On
Thermometer: Pazoma Oil Dipstick Thermometer with analogue dial readout
I will be testing more this week with hotter ambient temps, with fans on and off, will report results.
References:
Average truck engine oil bulk temp readout on EVIC is 220 degrees F.
Average Onan flathead air-cooled cylinder head temperature @ 1/2 load in 85F measured 330 degrees F (with full-time flywheel cooling fan)
Average Onan OHV air-cooled cylinder head temperature @ 1/2 load in 85F measured 270 degrees F (with full-time flywheel cooling fan)
Today's Ride Conditions:
Ambient air: 77 degrees F
Mileage: 24 mile trip (temp reading post-trip)
Route: mix of stop and go city, suburban access roads, rural highways.
Engine: '21 Heritage Classic M8 107, oil-cooled heads thru air cooler radiator
Love Jug Cylinder Head Fans: On
Thermometer: Pazoma Oil Dipstick Thermometer with analogue dial readout
I will be testing more this week with hotter ambient temps, with fans on and off, will report results.
Last edited by T^2; Aug 21, 2023 at 11:02 AM.
Seasoned HDF Member
Joined: Jan 2008
Posts: 13,674
Likes: 11,461
From: State of Confusion
good Lord man this is just one of your many comments on the subject...
"It's not just for saving oil and oil changes, it's for engine longevity. For those who say there's no difference, did you ever check your output power level running hot all the time? There is a difference. "
I looked up fussing in the dictionary and it said See Also; Old New rider
carry on, OCD analysis paralysis is free entertainment for me so please continue with your testing and reporting
"It's not just for saving oil and oil changes, it's for engine longevity. For those who say there's no difference, did you ever check your output power level running hot all the time? There is a difference. "
I looked up fussing in the dictionary and it said See Also; Old New rider
carry on, OCD analysis paralysis is free entertainment for me so please continue with your testing and reporting