Cooling My M8 Wet Head

Jun 25, 2017
25
15
Great Falls, MT, USA
Having issues getting the temps down on my 2017 TriGlide. Normal temperature for highway riding, (70-80MPH) runs in the 290-305 degrees, (hot to me). Ambient air riding temps are in the 80-95 degree range and we are at approximately 3400 feet of elevation.That's with approximately 500lbs of two up with gear riding. Have done several add-ons in my attempt to cool the trike, (the following is my setup). Have installed Love Jugs mighty mites, DK Customs 1 1/2 deluxe tank lift, DK Customs cooling deflector wings, DK Customs hi flow 606 air cleaner with EBS, removed left side thigh protector, power vision tuner and V&H trike deluxe slip ons. Been throwing a good bit of money at these high temps in my attempt to get them to a manageable range, (no luck so far). Looking for further advise on my setup. Is it possible I have a problem with my power vision tune? Next on the list will probably be a DK Customs oil filter relocate and oil cooler. I'm not sure adding them will drop the temps to a much safer range (230-270 degree). Guess you can say I've made improvements but nothing that has dropped the temps significantly. Looking for much needed recommendations or advise in my endless pursuit?
 
Having issues getting the temps down on my 2017 TriGlide. Normal temperature for highway riding, (70-80MPH) runs in the 290-305 degrees, (hot to me). Ambient air riding temps are in the 80-95 degree range and we are at approximately 3400 feet of elevation.That's with approximately 500lbs of two up with gear riding. Have done several add-ons in my attempt to cool the trike, (the following is my setup). Have installed Love Jugs mighty mites, DK Customs 1 1/2 deluxe tank lift, DK Customs cooling deflector wings, DK Customs hi flow 606 air cleaner with EBS, removed left side thigh protector, power vision tuner and V&H trike deluxe slip ons. Been throwing a good bit of money at these high temps in my attempt to get them to a manageable range, (no luck so far). Looking for further advise on my setup. Is it possible I have a problem with my power vision tune? Next on the list will probably be a DK Customs oil filter relocate and oil cooler. I'm not sure adding them will drop the temps to a much safer range (230-270 degree). Guess you can say I've made improvements but nothing that has dropped the temps significantly. Looking for much needed recommendations or advise in my endless pursuit?

Is your reading of 290-305 the "ET" read off the Power Vision or the "CHT" read?

If it is the ET read, yes, that is too hot, and it would seem that something is awry.

Adding the oil filter relo and oil cooler will drop the oil temps about 35*, which is significant and important. It will only drop the ET 5-7 degrees.

As I am typing, I think that must be the CHT read...the ET being that high is almost impossible with the Twin Cooled M8...unless no liquid cooling is passing thru the heads.

Kevin
 
Once you've done all the suggested mods + tune there's not much more that can be done.Folks I remember when 74" was a big motor.These engines get bigger every year yet we wonder why they are hot.Start up your car or pickup truck, open the hood and climb up there and sit on the motor-burned your arse didn't you?
 
Engine temps reported are from the Power Vision display. I'm not sure how to proceed or what to do next. Any suggestions are welcome?

Yes, but the Power Vision display has 2 different engine temps that it can display, they are titled:

ET

HeadT

These numbers will be very different, sometimes as much as 100* difference. When you look at the PV display, and see the 290 number (or whatever it is), what are the letters to the left of the number?

Need to know that in order to know how to proceed.

Kevin
 
Yes, but the Power Vision display has 2 different engine temps that it can display, they are titled:

ET

HeadT

These numbers will be very different, sometimes as much as 100* difference. When you look at the PV display, and see the 290 number (or whatever it is), what are the letters to the left of the number?

Need to know that in order to know how to proceed.

Kevin

Kevin, I'm home for lunch and went to the garage to check. Power Vision shows ET in (Fahrenheit).
 
Kevin, I'm home for lunch and went to the garage to check. Power Vision shows ET in (Fahrenheit).

That is not good at all. Something is wrong. Even bone stock in 100* ambient temps, you should not be getting that much heat.

It could be quite a variety of things, but the first thing I would do is ride it a bit, to get it warmed up, then pull the lower fairing cover on the right hand side and see if the coolant in the reservoir is hot. If it is not, that lets you know that the coolant is not circulating thru the heads.

With all the things you've done to cool it, it seems almost impossible for it be that hot, even if the coolant is not circulating. Do you have full power? It is not sumping, working against itself? Are the radiator fans kicking on? It could be any one or combination of those things.

There are just so many things it could be, but I would check the coolant first, and also see if it is throwing any codes.

If that is all good, then I would check the tune...but even a horrible tune should not be able to make it run that hot...but I would still check it.

Then I would check and make sure the anti-knock system is working.

If you need any assistance in checking any of the above, feel free to call.

I hate to say this, but if it were my bike, I would not ride it long enough to get it that hot, until whatever the issue(s) are are resolved. The ET is measuring the temp of the liquid cooled cylinder head, the rest of the engine is even hotter.

Kevin
 
That is not good at all. Something is wrong. Even bone stock in 100* ambient temps, you should not be getting that much heat.

It could be quite a variety of things, but the first thing I would do is ride it a bit, to get it warmed up, then pull the lower fairing cover on the right hand side and see if the coolant in the reservoir is hot. If it is not, that lets you know that the coolant is not circulating thru the heads.

With all the things you've done to cool it, it seems almost impossible for it be that hot, even if the coolant is not circulating. Do you have full power? It is not sumping, working against itself? Are the radiator fans kicking on? It could be any one or combination of those things.

There are just so many things it could be, but I would check the coolant first, and also see if it is throwing any codes.

If that is all good, then I would check the tune...but even a horrible tune should not be able to make it run that hot...but I would still check it.

Then I would check and make sure the anti-knock system is working.

If you need any assistance in checking any of the above, feel free to call.

I hate to say this, but if it were my bike, I would not ride it long enough to get it that hot, until whatever the issue(s) are are resolved. The ET is measuring the temp of the liquid cooled cylinder head, the rest of the engine is even hotter.

Kevin

Trike appears to have plenty of power to me. I will say that at speeds above 65 the trike does not have much power when passing other vehicles. That's comparing it to previous Harleys I've owned. When you say sumping is this in regard to oil migrating to tranny? I've been checking engine and tranny fluid frequently and see no evidence of either being low or excessively full. Fans do kick on and run most of the time. When engine is shut down after a ride the fans continue to run for some time.

I'm new to the PV and tuners but I'll check and see if I can figure out how to tell if codes are being thrown. Will take a small ride this evening after work and check to see if water pump is circulating through the fluid reservoir. No idea what anti-knock system does but will do a little research to see what I can find out about it.

Rather frustrating this heat issue, (I was wondering if this was somewhat normal for M8 motors) appears not to be the case. Any chance of somethin faulty within the PV?

I'll report back when I check the recommended items above.

Appreciate the suggestions and keep them coming if you have others.

Thanks
 
Trike appears to have plenty of power to me. I will say that at speeds above 65 the trike does not have much power when passing other vehicles. That's comparing it to previous Harleys I've owned. When you say sumping is this in regard to oil migrating to tranny? I've been checking engine and tranny fluid frequently and see no evidence of either being low or excessively full. Fans do kick on and run most of the time. When engine is shut down after a ride the fans continue to run for some time.

I'm new to the PV and tuners but I'll check and see if I can figure out how to tell if codes are being thrown. Will take a small ride this evening after work and check to see if water pump is circulating through the fluid reservoir. No idea what anti-knock system does but will do a little research to see what I can find out about it.

Rather frustrating this heat issue, (I was wondering if this was somewhat normal for M8 motors) appears not to be the case. Any chance of somethin faulty within the PV?

I'll report back when I check the recommended items above.

Appreciate the suggestions and keep them coming if you have others.

Thanks

Sumping is different than the migration issue. It occurs when the oil pump does not scavenge all the oil out of the bottom of the engine, and then the flywheels have to work their way thru that oil. It does cause a loss of power, and excessive heat. You should have good power above 65, it could be from the heat (which robs power) or it could be also from the flywheels working thru the oil (if it is sumping).

There are a few threads on here that give the procedure for seeing if the bike is throwing any codes. Here's a good one-

https://www.triketalk.com/forum/threads/43035-Harley-trouble-codes

Yes, there is always a chance that the PV is faulty, more likely the the temp sensor is faulty though.

Over the next few days I am not going to be on the internet much...just wanted to let you know in case it goes awhile without me responding.

Kevin
 
Richard, Sumping is NOT the same as the oil migration problem

If your engine was sumping you would most likely be way down on power, possible throwing codes

The sumping takes place in the crank case, too much oil dragging on lower end, oil not returning via oil pump to the oil pan. this could definitely cause the engine to struggle and run hotter.

My 17 Freewheeler ( oil cooled heads) has a PV tuner

It runs just a tad under 300 degrees on 90 + degree days

I have checked heat with an infra red gun and found the readings to not match the PV by quite a lot, I dunno if the placement on the M8 engines of the heat sensor now being in the rear head is causing these high readings.

Check your oil temperature just for grins IMO a Twin Cooled M8 should not be running as hot as you are seeing unless the PV is not accurate on the M8?
 
Sumping is different than the migration issue. It occurs when the oil pump does not scavenge all the oil out of the bottom of the engine, and then the flywheels have to work their way thru that oil. It does cause a loss of power, and excessive heat. You should have good power above 65, it could be from the heat (which robs power) or it could be also from the flywheels working thru the oil (if it is sumping).

There are a few threads on here that give the procedure for seeing if the bike is throwing any codes. Here's a good one-

https://www.triketalk.com/forum/threads/43035-Harley-trouble-codes

Yes, there is always a chance that the PV is faulty, more likely the the temp sensor is faulty though.

Over the next few days I am not going to be on the internet much...just wanted to let you know in case it goes awhile without me responding.

Kevin

Checked the PV and it has no codes found on DTCs screen. Will not get a chance to ride it tonight but will tomorrow and I'll check to see if I can tell if coolant is running through the reservoir. Thanks for the help Kevin.
 
Richard, Sumping is NOT the same as the oil migration problem

If your engine was sumping you would most likely be way down on power, possible throwing codes

The sumping takes place in the crank case, too much oil dragging on lower end, oil not returning via oil pump to the oil pan. this could definitely cause the engine to struggle and run hotter.

My 17 Freewheeler ( oil cooled heads) has a PV tuner

It runs just a tad under 300 degrees on 90 + degree days

I have checked heat with an infra red gun and found the readings to not match the PV by quite a lot, I dunno if the placement on the M8 engines of the heat sensor now being in the rear head is causing these high readings.

Check your oil temperature just for grins IMO a Twin Cooled M8 should not be running as hot as you are seeing unless the PV is not accurate on the M8?

Thanks for the explanation Jack. Your temps appear to be in the same range as mine other than the fact you are air cooled. Does the PV have oil temp as an option for display? Looks like I need to print out the manual for the PV user guide.
 
This thread has me a little concerned with my own setup. My 17 triglide runs an ET reported by my fp3 of between 287-292 @ 70+ mph in 90+ air temps. I too have a 2” tank lift, cooling deflector wings and a canned tune from an FP3. I’ve assumed this to be normal for the twin cooled M8?
 
This thread has me a little concerned with my own setup. My 17 triglide runs an ET reported by my fp3 of between 287-292 @ 70+ mph in 90+ air temps. I too have a 2” tank lift, cooling deflector wings and a canned tune from an FP3. I’ve assumed this to be normal for the twin cooled M8?

Dan, IMO the temperature gets reported to the ecm via a sensor in the back head behind the air cleaner instead of like the Twin Cams. They took their reading off the front cylinder, so the M8 will read engine temperature a bit hotter .
 
Thanks for the explanation Jack. Your temps appear to be in the same range as mine other than the fact you are air cooled. Does the PV have oil temp as an option for display? Looks like I need to print out the manual for the PV user guide.

I believe it does have an option for oil temp;)
 
Here is a response I got from Dynojet a few months back about Engine Heat on M8s

Thank you for your inquiry. We appreciate your interest and support of our products.

The engine temp that can be displayed on the Power Vision screen is read directly from whichever temperature sensor the ECM looks at. It is NOT an exhaust temp. Depending on where you’re located, those temps are not all that uncommon for a big twin in the summer. Out here in the deserts of Las Vegas, when our ambient temperature is 110+, it is not uncommon for me to see temps as high as 350 or so in stop and go traffic. I checked with one of our HD experts, who told me to only be concerned if the temp gets to 380… At which time, they recommended to pull over, shut the bike off and let it cool down.

If you have any questions, please feel free to contact us... We're open Monday-Friday, 8am-5pm Pacific time.

Scott Webster

Technical/Sales

Training Coordinator

Dynojet Research, Inc.
 
Here is a response I got from Dynojet a few months back about Engine Heat on M8s

Thank you for your inquiry. We appreciate your interest and support of our products.

The engine temp that can be displayed on the Power Vision screen is read directly from whichever temperature sensor the ECM looks at. It is NOT an exhaust temp. Depending on where you’re located, those temps are not all that uncommon for a big twin in the summer. Out here in the deserts of Las Vegas, when our ambient temperature is 110+, it is not uncommon for me to see temps as high as 350 or so in stop and go traffic. I checked with one of our HD experts, who told me to only be concerned if the temp gets to 380… At which time, they recommended to pull over, shut the bike off and let it cool down.

If you have any questions, please feel free to contact us... We're open Monday-Friday, 8am-5pm Pacific time.

Scott Webster

Technical/Sales

Training Coordinator

Dynojet Research, Inc.

That's some good to know information. Still want to get this trike cooled down as much as possible. I mentioned it earlier but the trike does not appear to have much get up and go when passing at 70mph or above. It will do it fine but you are not going to quickly move around a semi. Trike does great at holding speeds going up mountain passes. Definitely has much lower end grunt than my 2010 trike did, not so much on the higher end. I'm guessing but assume that has to do with the gearing. Hoping its not a heat issue that could be retarding it at the higher RPM's.

In a previous post you recommended checking oil temp. In your opinion what do you consider a safe zone for oil temp?
 
Hmmm ?

220 would be nice, mine checks in @ 250 with synthetic oil

OK, are you saying that the Power Vision can now read the engine oil temp on the M8 bikes? That is great if it will. I have never been able to find it as an option on my PV for my 2016 TC. I guess the PV is not able to get that from the ECM on the 16 and back models. Anybody else getting oil temp from the TC with a PV? I am going to check my PV menus again, but I don't think it will do it.

NOPE. I just hooked my PV up and checked for oil temp reading. It is not available for a gauge under the Advanced or Basic gauge options. Sure wish it was.
 
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OK, are you saying that the Power Vision can now read the engine oil temp on the M8 bikes? That is great if it will. I have never been able to find it as an option on my PV for my 2016 TC. I guess the PV is not able to get that from the ECM on the 16 and back models. Anybody else getting oil temp from the TC with a PV? I am going to check my PV menus again, but I don't think it will do it.

NOPE. I just hooked my PV up and checked for oil temp reading. It is not available for a gauge under the Advanced or Basic gauge options. Sure wish it was.

Thanks for checking Mike, I thought it was readable

It does have a coolant temp reading, I wonder what that would be on the Wet Heads?
 
That is not good at all. Something is wrong. Even bone stock in 100* ambient temps, you should not be getting that much heat.

It could be quite a variety of things, but the first thing I would do is ride it a bit, to get it warmed up, then pull the lower fairing cover on the right hand side and see if the coolant in the reservoir is hot. If it is not, that lets you know that the coolant is not circulating thru the heads.

With all the things you've done to cool it, it seems almost impossible for it be that hot, even if the coolant is not circulating. Do you have full power? It is not sumping, working against itself? Are the radiator fans kicking on? It could be any one or combination of those things.

There are just so many things it could be, but I would check the coolant first, and also see if it is throwing any codes.

If that is all good, then I would check the tune...but even a horrible tune should not be able to make it run that hot...but I would still check it.

Then I would check and make sure the anti-knock system is working.

If you need any assistance in checking any of the above, feel free to call.

I hate to say this, but if it were my bike, I would not ride it long enough to get it that hot, until whatever the issue(s) are are resolved. The ET is measuring the temp of the liquid cooled cylinder head, the rest of the engine is even hotter.

Kevin

Got a chance to ride it this morning and warmed it up, (252 degrees ET on PV). Only took about 6 miles with rpm's between 2200 and 3000. Speeds in town are all under 45 mph. Pulled the right side cover and reservoir is warm as in I can hold it all day long. Definitely not hot by any means. Coolant fans are running and and exhausting on both lowers. Any further suggestions?
 
Got a chance to ride it this morning and warmed it up, (252 degrees ET on PV). Only took about 6 miles with rpm's between 2200 and 3000. Speeds in town are all under 45 mph. Pulled the right side cover and reservoir is warm as in I can hold it all day long. Definitely not hot by any means. Coolant fans are running and and exhausting on both lowers. Any further suggestions?

I am stumped, I would expect @ 252 the coolant would be hotter in the reservoir

I wonder what your oil temp is?

Have you got a thermometer you can stick in the oil tank hole?
 
I am stumped, I would expect @ 252 the coolant would be hotter in the reservoir

I wonder what your oil temp is?

Have you got a thermometer you can stick in the oil tank hole?

No thermometer Jack. I'll head over to O'reillys or autozone and see if they have one.

Why would the reservoir be hot? Is it not just a holding tank for the system if it needs more or less fluid?

I believe my coolant temp got up to about 191 on that little run. Maybe not hot enough for the fluid to pull or add to the tank? I'll do another run shortly and see what I get for ET and Coolant temp and report back.
 
No thermometer Jack. I'll head over to O'reillys or autozone and see if they have one.

Why would the reservoir be hot? Is it not just a holding tank for the system if it needs more or less fluid?

I believe my coolant temp got up to about 191 on that little run. Maybe not hot enough for the fluid to pull or add to the tank? I'll do another run shortly and see what I get for ET and Coolant temp and report back.

I was thinking lowers not reservoir

I believe I could live with 191 with both fans on, tho your ride was short

The oil temp will tell a good story once you know its value IMO
 
I was thinking lowers not reservoir

I believe I could live with 191 with both fans on, tho your ride was short

The oil temp will tell a good story once you know its value IMO

Just returned from an 80 mile ride to see what the variation in temps would be. Cruise set at 70 mph at around 3000 rpm.

Highly unscientific for oil temp but used one digital and two deep frier thermostats. Best I could determine for oil temp was 232. This was shutting the trike down and immediately checking.

ET and coolant temps are from the PV. The ET and coolant temps very depending on terrain traveled. On the rolling hills around Great Falls I will say the temps average around 217 for the coolant and 297 for ET.

Going up a pretty good grade on a mountain pass with twisted at 70 rather aggressively I had a high of 230 on the coolant temp and 306 on the ET.

Pulled the right lower cover, (engine running) when I got on top to see if the radiator had been pulling any fluid from the reservoir. Once again I could hold my hand on the tank and it was not hot at all.

Trike had plenty of power throughout the ride. The darn thing is a torque monster compared to my 2010 trike.

No idea what to check next. Any suggestion from the forum are welcome.
 
I dunno but I think the ET is too high for a wet head

IMO. The temp is taken in a very hot part of the engine compared to the front cylinder reading on Twin Cams so I would expect it to be hotter, the M8 definitely cools down faster than Twin Cams

Your coolant temp looks good to me and your oil temps are where they should be

I have high ET some times with my M8 oil cooled but my oil temps are consistent in the range they need to be

I am not too worried, I have put over 17 K miles on now since I have been watching my PV and No bad Ju Ju yet

Just for grins if you know someone that has an infra red thermo give it a shot after a ride and compare your readings to what the PV is showing, you will probably be as surprised as I was
 
sounds somewhat normal to me

I dunno but I think the ET is too high for a wet head

IMO. The temp is taken in a very hot part of the engine compared to the front cylinder reading on Twin Cams so I would expect it to be hotter, the M8 definitely cools down faster than Twin Cams

Your coolant temp looks good to me and your oil temps are where they should be

I have high ET some times with my M8 oil cooled but my oil temps are consistent in the range they need to be

I am not too worried, I have put over 17 K miles on now since I have been watching my PV and No bad Ju Ju yet

Just for grins if you know someone that has an infra red thermo give it a shot after a ride and compare your readings to what the PV is showing, you will probably be as surprised as I was

230 to 250 on oil temp is not out of the norm on a 100 deg day (would suggest you use synthetic oil and not HD oil), think the manual states 230 as normal, as far as your cooling system If your cooling fans are coming on and going off I would think they are working correctly (on @ 90 C , off @ 83 C. My concern would be what map you have loaded from your PV and what your fuel tables are set at ? a can map is exactly that one to start with and make adjustments to fit your needs. the injectors on the original bike tuned will be a little different than what yours are and your VE tables will also be slightly different 14.4 in the cruse range is about where you want to be 2000 rpm to 35 or 3700 RPM up to about the 80 KPA throttle range, from what you are saying here I would guess your total weight is around 1800 lbs loaded going up and down hills with a pretty much stock bike downshifting to pass always helps even on two wheels, and most stock HD cams are done putting out torque by 3000 to 3500 RPM and start to nose over on the chart. just my two cents and I do understand your concerns Im in the process of modifying the wifes tri Glide due to the heat coming off the engine and putting blisters on her leg. as well as oil transfer from trans to primary.
 
sounds somewhat normal to me

what map are you using and have you done any other tuning since installing map. your numbers sound normal for

a tri glide or a harley in general, 230 - 250 oil temp not out of the question. coolant temps must be normal if your fans are working ( on at 90 C off @ 83C. and no HOT light on gauges. just rolling the throttle on to pass will work if you have lots of room but the engine will do better if you drop down to 5th gear to pass. cooling fans dont do much at 70 MPH. My wife got blisters on her right leg from her TG , In the process of doing mods to help it out,

BUT it is still a big air cooled engine (only the exhaust port is liquid cooled) for the most part and will put out lots of heat when worked hard and yes to me 1500 to 1800 hundred LBS climbing hills is working the motor.
 

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