M8 Twin Cooling engine temp info - don't close those vents!!
#21
04-15-2017, 05:05 PM
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My 2017 CVO Limited Stage IV factory map and my FM Powervision tuned map doesn't pull spark until 284 degrees. In your road testing did you have the lower vents FULLY open? If they were closed or only partially open, I found using my Powervision, that Engine Temp, Head Temp and Coolant temps, will climb quickly (ET300+, HT320+, CT220+) and higher even in cool air temps.
Otherwise everything you experienced is exactly what I experienced. To optimize performance of a twin-cooled bike, its critical to keep the lower vents FULLY open and the coolant level full. Even then, it may be a struggle to keep the engine temps below 284 (when performance really degrades) once the summer arrives.
Otherwise everything you experienced is exactly what I experienced. To optimize performance of a twin-cooled bike, its critical to keep the lower vents FULLY open and the coolant level full. Even then, it may be a struggle to keep the engine temps below 284 (when performance really degrades) once the summer arrives.
Our benchmark for testing is the ET off the PV, which is pulled from the ECM and is the reading from the front cylinder head sensor, and it is always lower than the head temperature reading (which is also pulled from the ECM), which is what the ECM looks at to pull timing.
The ET is a much more stable number and we've just found it is a better indicator of overall heat that the entire engine is experiencing.
The variance between the ET and the FHT can be as little as 20* and as much as 100*, or more, all depending on the load.
If a bike is properly cooled (non-factory set-up) the ET and the oil temp will closely mirror each other.
Just this afternoon I was riding for a ways on the interstate and all temps warmed up and stabilized. This was on a Twin-Cooled bike, that has multiple cooling strategies in place.
Ambient 83*
Speed 75 mph with no significant wind
ET 212*
Head Temp. 280* (calculated by the ECM, not an infra red gun)
Coolant 174*
Oil 218*
While the ECM begins pulling timing around 284*, it does not start making significant changes to the timing until around 320*, and gets more and more aggressive above that number.
So when we look at the ET, we know that above 250* we are well above 320 FHT and performance is suffering and metal is getting too hot and experiencing accelerated wear.
And no matter what the oil companies advertise, even the best oil begins breaking down around 270*.
That is why 250* is the safe number we never want to go above...that give a 20* margin before bad things start happening.
We still have a lot of testing to do on both the Twin-Cooled & Oil-Cooled M8's, but everything we've seen so far regarding engine & oil heat* is the same as the Twin Cam.
*(not felt heat...the M8 is better than the TC in that area)
Heat REPORT link.
Last edited by DK Custom; 04-15-2017 at 06:41 PM.
#22
04-15-2017, 05:57 PM
Seasoned HDF Member
snip
The ET is a much more stable number and we've just found it is a better indicator of overall heat that the entire engine is experiencing.
The variance between the ET and the FHT can be as little as 20* and as much as 100*, or more, all depending on the load.
If a bike is properly cooled (non-factory set-up) the ET and the oil temp will closely mirror each other.
snip
The ET is a much more stable number and we've just found it is a better indicator of overall heat that the entire engine is experiencing.
The variance between the ET and the FHT can be as little as 20* and as much as 100*, or more, all depending on the load.
If a bike is properly cooled (non-factory set-up) the ET and the oil temp will closely mirror each other.
snip
#23
04-15-2017, 06:15 PM
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ET is a direct measurement of the front head at the sensor & is used for most of the lookup tables including the fuel tables and multipliers, while Head Temp, which is the algorithm based number, is used primarily for spark temp correction.
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Max Headflow (04-15-2017)
#24
04-15-2017, 11:53 PM
On the M8 that I referenced above it was an oil-cooled only, with no lower fairings.
Our benchmark for testing is the ET off the PV, which is pulled from the ECM and is the reading from the front cylinder head sensor, and it is always lower than the head temperature reading (which is also pulled from the ECM), which is what the ECM looks at to pull timing.
The ET is a much more stable number and we've just found it is a better indicator of overall heat that the entire engine is experiencing.
The variance between the ET and the FHT can be as little as 20* and as much as 100*, or more, all depending on the load.
If a bike is properly cooled (non-factory set-up) the ET and the oil temp will closely mirror each other.
Just this afternoon I was riding for a ways on the interstate and all temps warmed up and stabilized. This was on a Twin-Cooled bike, that has multiple cooling strategies in place.
Ambient 83*
Speed 75 mph with no significant wind
ET 212*
Head Temp. 280* (calculated by the ECM, not an infra red gun)
Coolant 174*
Oil 218*
While the ECM begins pulling timing around 284*, it does not start making significant changes to the timing until around 320*, and gets more and more aggressive above that number.
So when we look at the ET, we know that above 250* we are well above 320 FHT and performance is suffering and metal is getting too hot and experiencing accelerated wear.
And no matter what the oil companies advertise, even the best oil begins breaking down around 270*.
That is why 250* is the safe number we never want to go above...that give a 20* margin before bad things start happening.
We still have a lot of testing to do on both the Twin-Cooled & Oil-Cooled M8's, but everything we've seen so far regarding engine & oil heat* is the same as the Twin Cam.
*(not felt heat...the M8 is better than the TC in that area)
Heat REPORT link.
Our benchmark for testing is the ET off the PV, which is pulled from the ECM and is the reading from the front cylinder head sensor, and it is always lower than the head temperature reading (which is also pulled from the ECM), which is what the ECM looks at to pull timing.
The ET is a much more stable number and we've just found it is a better indicator of overall heat that the entire engine is experiencing.
The variance between the ET and the FHT can be as little as 20* and as much as 100*, or more, all depending on the load.
If a bike is properly cooled (non-factory set-up) the ET and the oil temp will closely mirror each other.
Just this afternoon I was riding for a ways on the interstate and all temps warmed up and stabilized. This was on a Twin-Cooled bike, that has multiple cooling strategies in place.
Ambient 83*
Speed 75 mph with no significant wind
ET 212*
Head Temp. 280* (calculated by the ECM, not an infra red gun)
Coolant 174*
Oil 218*
While the ECM begins pulling timing around 284*, it does not start making significant changes to the timing until around 320*, and gets more and more aggressive above that number.
So when we look at the ET, we know that above 250* we are well above 320 FHT and performance is suffering and metal is getting too hot and experiencing accelerated wear.
And no matter what the oil companies advertise, even the best oil begins breaking down around 270*.
That is why 250* is the safe number we never want to go above...that give a 20* margin before bad things start happening.
We still have a lot of testing to do on both the Twin-Cooled & Oil-Cooled M8's, but everything we've seen so far regarding engine & oil heat* is the same as the Twin Cam.
*(not felt heat...the M8 is better than the TC in that area)
Heat REPORT link.
I did a 100 mile ride today with temps in the 50's and 60's. The PV showed "normal" operatings temps around 250 give or take 10 degrees. Head temps under normal operating temps are about 15 degrees higher (260-270). And the coolant temps around 160-170.
Get into higher rpm riding conditions in the twisties or 2-up riding and its easy to jump the ETs to 300, the HTs to 330 and even much higher. And the coolant temps can easier rise above 210. Once the bike ETs get above 300 it can be a challenge to get them back into the 250 range until the bike is shut down.
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Max Headflow (04-16-2017)
#25
04-17-2017, 03:19 PM
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Good summary. It matches my findings reasonably but I could be different as I have the Stage IV upgrade with the CNC ported heads along with a larger TB, injectors and 515 cam.
I did a 100 mile ride today with temps in the 50's and 60's. The PV showed "normal" operatings temps around 250 give or take 10 degrees. Head temps under normal operating temps are about 15 degrees higher (260-270). And the coolant temps around 160-170.
Get into higher rpm riding conditions in the twisties or 2-up riding and its easy to jump the ETs to 300, the HTs to 330 and even much higher. And the coolant temps can easier rise above 210. Once the bike ETs get above 300 it can be a challenge to get them back into the 250 range until the bike is shut down.
I did a 100 mile ride today with temps in the 50's and 60's. The PV showed "normal" operatings temps around 250 give or take 10 degrees. Head temps under normal operating temps are about 15 degrees higher (260-270). And the coolant temps around 160-170.
Get into higher rpm riding conditions in the twisties or 2-up riding and its easy to jump the ETs to 300, the HTs to 330 and even much higher. And the coolant temps can easier rise above 210. Once the bike ETs get above 300 it can be a challenge to get them back into the 250 range until the bike is shut down.
Yeah, Devin, the "D" in DK has a Stage IV. It produces more heat, faster too.
They key is to use some additional cooling options so that it never crosses that line where it is difficult for it to cool down while riding.
#26
04-18-2017, 09:09 AM
On the M8 that I referenced above it was an oil-cooled only, with no lower fairings.
Our benchmark for testing is the ET off the PV, which is pulled from the ECM and is the reading from the front cylinder head sensor, and it is always lower than the head temperature reading (which is also pulled from the ECM), which is what the ECM looks at to pull timing.
The ET is a much more stable number and we've just found it is a better indicator of overall heat that the entire engine is experiencing.
The variance between the ET and the FHT can be as little as 20* and as much as 100*, or more, all depending on the load.
If a bike is properly cooled (non-factory set-up) the ET and the oil temp will closely mirror each other.
Just this afternoon I was riding for a ways on the interstate and all temps warmed up and stabilized. This was on a Twin-Cooled bike, that has multiple cooling strategies in place.
Ambient 83*
Speed 75 mph with no significant wind
ET 212*
Head Temp. 280* (calculated by the ECM, not an infra red gun)
Coolant 174*
Oil 218*
While the ECM begins pulling timing around 284*, it does not start making significant changes to the timing until around 320*, and gets more and more aggressive above that number.
So when we look at the ET, we know that above 250* we are well above 320 FHT and performance is suffering and metal is getting too hot and experiencing accelerated wear.
And no matter what the oil companies advertise, even the best oil begins breaking down around 270*.
That is why 250* is the safe number we never want to go above...that give a 20* margin before bad things start happening.
We still have a lot of testing to do on both the Twin-Cooled & Oil-Cooled M8's, but everything we've seen so far regarding engine & oil heat* is the same as the Twin Cam.
*(not felt heat...the M8 is better than the TC in that area)
Heat REPORT link.
Our benchmark for testing is the ET off the PV, which is pulled from the ECM and is the reading from the front cylinder head sensor, and it is always lower than the head temperature reading (which is also pulled from the ECM), which is what the ECM looks at to pull timing.
The ET is a much more stable number and we've just found it is a better indicator of overall heat that the entire engine is experiencing.
The variance between the ET and the FHT can be as little as 20* and as much as 100*, or more, all depending on the load.
If a bike is properly cooled (non-factory set-up) the ET and the oil temp will closely mirror each other.
Just this afternoon I was riding for a ways on the interstate and all temps warmed up and stabilized. This was on a Twin-Cooled bike, that has multiple cooling strategies in place.
Ambient 83*
Speed 75 mph with no significant wind
ET 212*
Head Temp. 280* (calculated by the ECM, not an infra red gun)
Coolant 174*
Oil 218*
While the ECM begins pulling timing around 284*, it does not start making significant changes to the timing until around 320*, and gets more and more aggressive above that number.
So when we look at the ET, we know that above 250* we are well above 320 FHT and performance is suffering and metal is getting too hot and experiencing accelerated wear.
And no matter what the oil companies advertise, even the best oil begins breaking down around 270*.
That is why 250* is the safe number we never want to go above...that give a 20* margin before bad things start happening.
We still have a lot of testing to do on both the Twin-Cooled & Oil-Cooled M8's, but everything we've seen so far regarding engine & oil heat* is the same as the Twin Cam.
*(not felt heat...the M8 is better than the TC in that area)
Heat REPORT link.
Screenshot from my SE smart tune session (2017 M8 stage 2 torque). This is with the fan assisted oil cooler on a unseasonably warm 90 degree day in Mass. I've done a ton of lurking in these M8 threads in regards to managing engine heat both for the bikes well being and my passenger.
Wondering if my high numbers during this session are due to the bike being in programmer (smart tune) mode or if this is what it is?
Granted I was was riding it like I stole it a few times during the recording, but the ET and HT seem high.
#27
04-18-2017, 11:24 AM
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Screenshot from my SE smart tune session (2017 M8 stage 2 torque). This is with the fan assisted oil cooler on a unseasonably warm 90 degree day in Mass. I've done a ton of lurking in these M8 threads in regards to managing engine heat both for the bikes well being and my passenger.
Wondering if my high numbers during this session are due to the bike being in programmer (smart tune) mode or if this is what it is?
Granted I was was riding it like I stole it a few times during the recording, but the ET and HT seem high.
Don't get me wrong, I really am digging the M8 and the potential it has above the Twin Cam, I really like what HD did. But, the heat is still an issue.
In this LINK there is a list of what you can do to cool down your M8 to get better performance and better engine longevity.
#28
04-18-2017, 11:45 AM
Unfortunately those temps seem typical of the oil cooled M8, just as they are of the Twin Cams.
Don't get me wrong, I really am digging the M8 and the potential it has above the Twin Cam, I really like what HD did. But, the heat is still an issue.
In this LINK there is a list of what you can do to cool down your M8 to get better performance and better engine longevity.
Don't get me wrong, I really am digging the M8 and the potential it has above the Twin Cam, I really like what HD did. But, the heat is still an issue.
In this LINK there is a list of what you can do to cool down your M8 to get better performance and better engine longevity.
Bookmarked your site
#29
04-18-2017, 03:09 PM
HD EFI Guru
The way you make power is you make heat. How well you convert the heat in to mechanical energy, reduces the heat left over, that has to go somewhere else. So as you increase power you increase heat, just the way it works and there is no getting around it. So one must deal with the left over heat coming from the engine. It's not hard to do just a matter of understanding where it is coming from and the best way to deal with it. You want to take the hottest thing and cool it with the coldest thing you can. In the case of an oil cooled engine the oil and air flow around the engine is all you have to work with. With a Water cooled HD you also get to work with the water temperature, so you must balance the items you can. Not much can be done for airflow around and engine at low vehicle speeds other than add a fan or two to increase that airflow. Placing a fan right next to t temperature sensor gives you a False reading so that not always a god thing to do. Do it carefully so your not get misinformation as you can get led astray when doing it wrong.
#30
04-18-2017, 04:24 PM
Road Warrior
UPDATE!!!!
MoCo killed my warranty today over the FP3! Harley Dude, Dano did not offer up his card or real name just kissed his boss's ***. A man my size,,, just folded like a *** in a bath house. Low oil psi killed the M8.
I asked the dealer owner where the nearest U-Haul was and to inventory all my bikes parts. And he ask me to leave the bike with him. He has not played all his cards yet.
So the Harley USA saga rolls on. I agreed to not start litigation because of a bit of respect and a hand shake with the owner of my dealer.
MoCo killed my warranty today over the FP3! Harley Dude, Dano did not offer up his card or real name just kissed his boss's ***. A man my size,,, just folded like a *** in a bath house. Low oil psi killed the M8.
I asked the dealer owner where the nearest U-Haul was and to inventory all my bikes parts. And he ask me to leave the bike with him. He has not played all his cards yet.
So the Harley USA saga rolls on. I agreed to not start litigation because of a bit of respect and a hand shake with the owner of my dealer.