It’s a trick you gain with sperience

 

After the group ride today I tanked up and hand calculated my MPG. It calculated it out at 39.91 MPG. I'm running the stock tune. Later, I'll do a smart tune or two but as of now I am happy.

Now about 100 miles of our ride was on the Natchez Trace with a 50 mph speed limit. I had my cruise set on 51 mph and we made a few stops. We had another 70 or so miles going though Natchez then Vidalia La and 55 mph speed limits.
I assume a long run on a 75 mph speed limit, the milage will drop some.

 

Cool, glad you have found some of our videos interesting/useful.

That air cleaner is feeding hot, oily, oxygen depleted air into the intake. You can add and External Breather System to it that will take care of that, but the filter element in that air cleaner is too small for an OEM set-up...it will start starving for air at higher RPM's...and then if you go with a bigger cam, the small element will hold it back even more.

A very important part of a good foundation, as talked about in the first video shown above, is getting the temps down to optimum. That makes a huge difference in power and longevity for the engine. Here is a LINK to a written report on the subject, and below is a video on the subject.

 

Thank you so much for your reply. I watched the video you linked to and enjoyed watching it.
I agree with everything you guys talked about in the vid.

I'm sure there are more changes I need to make to get better performance and better protection for my engine due to heat.
Right now, it's pretty much what it is with my upgrades. I'll upgrade more up as I get closer to my warranty expiration.

I set my phone up to read the undesirable Screaming Eagle Pro Street Tuner. I don't get to see some of the things I'd desire on the available gauges But a couple things I can read is engine temp and air intake temp.
I took a 30 mile trip today watching my monitored gauges and noticed the engine temp got up to 301 deg at one point with air inlet temp running at 140 deg.
I was running 62 mph for most of the trip and the ambient temp was 94 deg. The rest of the time my engine temp was down to 184 or less in slower speeds.

I have not performed a smart tune as of yet with the SE but will in the very near future. I'd like to see how that effects my engine temp. What I don't understand yet is why my air inlet temp is at 140 deg with an ambient temp of 94 deg.

 

Heat of the engine, and airspeed through the intake tract, affects the air inlet temp. Normal for the ambient to be less than air inlet, they should be close or equal at cold start, and the difference becomes increased as the bike warms up.
My 131 runs 350ish head temp running down the highway at 75 MPH with ambient temps low to mid 90s.

 

There are a couple of reasons your intake temp is more than the ambient.
1. The air cleaner is bolted to the hottest part of the engine and that metal of the air cleaner absorbs some of that heat and heats up the air flowing thru it. With your air cleaner, at least it is not an enclosed hot box, and there is not a lot you can do about the transfer of heat (other than to lower the engine temp to the optimum range, which for your M8 is between 230 and 260 F.) More info on that below.

2. All the hot, oily, oxygen depleted air from the crankcase is going into the air cleaner, and that heats up the intake air temperature. Here is a LINK to a written report on exactly how that works. And here is a video with info about an EBS.



Before looking at any temperatures, we realize that it takes 30-45 minutes of riding (even in warm weather) to get the engine fully warmed up.

Regarding "engine temps", folks measure a bunch of different things to see what their engine temp is. We use only two measurements. They are shown in the video below.


230 F is what Harley says is the normal operating temp for the oil. This is at the high end, but it is still ok.

Harley also has the bikes ECM set up to start pulling power when the engine temp (as measured by the cylinder head temp sensor) hits 270 F. At that temp, and higher, the engine begins getting sluggish, and accelerated wear is occurring. Below is a video showing what happens, in real time, when the engine temp crosses 270 F.


Because of these factors, our top two things we measure for maintaining engine health are the oil & engine temp.

Hopefully your Smart Tune will get that engine temp down 5-10 degrees, which will still be too hot (coming from 300 f), but still, every improvement helps.

Nobody wants to end up like this guy-

 

Thanks guys. It appears I need to redo the air cleaner and go with a EBS.

 

What kind of cover is on the air cleaner? Running an open air filter may help. On a 100 degree day my intake air temp runs around 120 degrees going down the highway at 75. I've been tempted to put the 103 Rushmore cover back on to see how much of a difference it makes.

 

I don't quite understand the question. The cleaner is a Screaming Eagle. The filter element is made by K&N if that's what you are asking.

 

Is the filter exposed like this or does it have a cover around it?


This is the 103 Rushmore cover I mentioned. It may, or may not, cause cause hotter air from the engine to be drawn into the intake.