Viewing an inclusive M8 video at the HD show from the largest LA HD dealership, Laidlaw, stated that the new M8 series offers a much more advanced oil cooling system relet with an oil cooler. Is this true for both the 107/114 or just the 107 version which does not have the 114 water cooling set-up? Thank you.

 

Oil coolling for all engines that are not water cooled. It is one or the other.

 

There is nothing fancy or advanced about the oil cooler on the 2017 M8, sorry but that's only advertising at its finest. As a matter of fact the oil cooler on the M8 ONLY cools the oil that is feed to the heads for cooling, the rest of the oil does not even go to the cooler. The water cooled models just replace the oil cooling with water cooling. So you end up with two different systems and the CVO 114 only comes water cooled, the 107 comes with one or the other depending on bike model.

 

I don't think this is right - or maybe explained clearly. There are not two oil systems on those bikes. Just one.
The engine has a bigger oil pump to push oil from it's one source (oil pan) though the cam plate and all it's internal engine parts AND out to the oil cooler which cools it and sends the oil up and over the top of the engine into the heads/ports. It then returns the oil down from the heads back into the oil pan passing through the top of the trans case.

So all of the oil at one time or another goes through the oil cooler...

The water cooling system IS separate and does not share anything other than using the same head ports the oil system would.

 

^ like the XR1200 did.

 

It looks correct to me.. The Oil cooled system has an oil cooler and liquid cooled has a radiator. The liquid cooled does not have an oil cooler.

 

I disagree. All oil comes from the oil pan at one time or another but that in no way means it ALL goes into the cooler. Only a part of the oil ends up in the cooler and if this part is not cooling the engine enough then we can have the temperature issues that we are already seeing in the engine temperature readings. The cooled oil then goes into the heads around the exhaust valves and gets super heated and returned to the pan.

For the record taking a cold engine and recording the data on a 18 mile ride at highway speeds shows the engine temperature climbing the entire time! It never stops getting hotter and that was on a 75 deg day and highway speeds of 55 - 75 MPH flat ground cruise the entire time! Engine temperature started at 70 degrees and continued to climb to 330 degrees! This was on a 107 Stage I bike!
The same bike, run in town at 35 - 50 mph with little to no traffic other than normal stopping at traffic lights did climb to 345 degrees and then cooled to 335 when at speed of about 45mph. Again, this was only a 78 degree ambient temperature day! What's it going to do in 110 ambient temperatures? I rode it into traffic and after several blocks of So. Cal. traffic it had climbed to 360 degrees and I pulled it over and shut it off to cool.

This is just why I'm worried about it and we are adding a temperature probe into the oil pan area to measure Oil temperature in the pan, to see what it's doing. Remember that a Sportster is only 883 or 1200 cc and what worked on it may not work on the larger displacements. FWIW ALL oil cooled trikes get an oil cooler with a fan, so HD must be worried about something or why add it. I have ordered one of those oil cooler kits so we can put it on and see what the differences are.

 

Steve Cole,

What temperature issues are you talking about? I thought the only issues so far with the M8 have been with the oil pump (low oil pressure) and oil leaks (various, but the most notable is a cracked case from over tightening a plug). Most people have reported the M8 running cooler than a twin cam no matter what displacement or cooling configuration. Why are you comparing a Sportster cooling to an M8. The Sportster was not the predecessor of the M8. If the purpose is because if displacement,HD big twins of various families have featured larger displacements than Sportster engines for longer than many forum members have been alive and were cooled just fine.

I seriously doubt an M8 is going to melt no matter what month we are in unless there is a major malfunction. Your first post did imply two oil systems which of course was wrong.

Harley is not in any way shape or form in a panic about engine temperature or oil temperature. If you look at how the motor company operates, historically they look at the most common easily performed mods by making observations at rallies and other events and look at what aftermarket companies are offering that sell well, then offer that as OEM. This applies to styling as well as functional items. Twin Cams were known to run warm, mostly due to lean tuning but other factors as well. Among the popular mods was the addition of an oil cooler. Oil cooled heads in the twin cam Rushmore's were well received, so that concept was carried over to the M8. If you look at the combustion chamber design, you will see why less heat is being transferred to the head in M8's.

 

I don't think I understand the idea being presented that the oil cooled 107 M8 engine has some oil that goes thru the oil cooler and some doesn't.

It's a single pump system. That means at one time or another all the oil will travel thru the sump, the oil pump, the cam plate, lifters, top end, cooling passages around the exhaust valves & port and the oil cooler. The oil follows a pressurized pathway with the oil cooler in that pathway. To me, it stands to reason that all the oil in that pathway eventually goes thru the oil cooler and every thing else.

I'm not here to argue, I'm here to say how can it be any other way?

 

Perceived running cooler and running cooler are two different things. Moving the exhaust away from the riders leg and thigh along with moving the cat reward have help the feel of the heat coming from the engine. NO Twin Cam has ever had Oil cooled heads only Water cooled or Air cooled. The Sportster did have a oil cooled head version and that was brought up (post #5) so I addressed it. Look around for the temperature measurements from the cylinder heads and you will find the hotter running temperatures are being reported by others as well. The engine temperatures show hotter than a Twin Cam in like conditions, so running lean has nothing to do with it at all, as both engines run at near the exact same mixtures except at WOT. As for how the head looks and works I know it very well and as for my first post please show me where I said there were two oiling systems. I only stated how it really works.

Let compare a few things between the Twin Cam engine and the M8 that may straighten a few of you out. EITMS is a feature to keep ride perceived heat down, but doesn't mean the engine is any cooler. This is perceived heat!

The Oil Cooler on the M8 is NOT in the path of all the oil! As the oil leaves the engine case part/some of it is sent out to the oil cooler then up to the cooling passages in the heads only then back into the sump. The balance of the oil is sent to the oil filter then back into the engine to lubricate everything, never seeing the oil cooler. On a TwinCam all the oil goes to the filter then to the Oil Cooler if equipped and then back to the engine.

Twin Cam
Water Cooled Models active EITMS at Engine temp 185 deg C or above 27 deg C Ambient Air Temp
Cooling Fans active above 105 deg C
Air Cooled Models active EITMS at Engine temp 165 deg C
There are no Cooling Fans

So there is no extra cooling efforts until those temperatures are reached

M8
Water Cooled Models active EITMS at Engine temp 90 deg C or above 27 deg C Ambient Air Temp
Cooling Fans active above 90 deg C
Oil Cooled Models active EITMS at Engine temp 142 deg C
There are no Cooling Fans

So there is no extra cooling efforts until those temperatures are reached, so why did HD lower the settings so far? Remember this is just for rider comfort not that the engine is running cooler!

So HD has really lowered the temperature settings down to give more rider comfort in slow traffic conditions and on the water cooled model turn the cooling fans on very early and they run much longer on a M8 than a Twin Cam. So if I lowered the settings in a Twin Cam to match a M8 and then moved the rear exhaust pipe away from the riders leg/thigh then moved the CAT rearward I bet you would get the same feeling but it has nothing to do with the real running temperatures! The changes are a good thing for the riders.

So what really needs to be determined is why are the heads are showing more temperature by about +20 deg on a M8 than a Twin Cam and I believe that Oil temperature will let us know what's really going on.

There have also be a few reports of exhaust valve seat and exhaust stem/guide issues report. Not saying that a few reports is enough to worry about but it is something to keep in mind while doing development work as I do.