Ok, I repeated the test this morning, this time:
- at higher ambient outdoor temperature (62 to 72F)
- maintaining a constant highway speed of 100 kph = 62 mph, except when changing highways.

Here are the results:




This might not be what Kevin at DK Customs might have expected, but it is what actually happened over a ride duration of 1 hour and 19 minutes.

The difference between sustained oil temperature and sustained reported engine cylinder head temperature is pretty substantial (the oil was an average of 76 degrees cooler!).

The chart above does not show the relative instability of cylinder head temperature. During the ride, I BRIEFLY saw temperatures over 300 degrees, as high as 311, but the "snapshots above", captured approximately 10 kilometers apart (whenever a safe place to stop on a wide enough shoulder occurred), did not capture those because they were THAT brief and that rare as a percentage of total travel time.

Both cylinder head temperature and oil temperature are important, but the cylinder head temperature varies a lot more, more frequently, and more briefly, than the oil temperature does. This is good news for oil life.

Jim G

 

I just thought of a possible complicating variable: Yesterday's test run was made with the HD Stage 1 tune installed, but while running the Smart Tune "data recording" session. That recording session, by definition, plays with AFR (flashes the changing status of the two O2 sensors on the iPhone screen in fact while doing so). In theory at least, that could have SLIGHTLY affected the engine cylinder head temperature and the oil temperature, but I cannot see it affecting the oil temperature very much.

Today's test run was made with the results from that data recording session incorporated into the OEM Stage 1 tune to make it a Stage 1 tune now customized to my specific engine. Again, that could at least theoretically affect both cylinder head and oil temperatures. But again, the cylinder temperature has now been proven to be very volatile to begin with, and the oil temperature has been proven to be very slow to change. So again, I doubt that any impact of the customized tune was significant in the 2 temperatures.

As an aside, for whatever reason, the customized tune for the trike's 114 was notably less dramatic in its effects, than the customized tune for the Breakout 117.

The Breakout tune made the Breakout smoother, snappier in throttle throttle response, and noticeably quicker in acceleration.

The trike tune made the trike smoother, somewhat snappier in throttle response (but notably less effect than on the Breakout), and manifested the most when accelerating relatively hard from a stop to 100 kph = 62 mph. It might be reasonable to assume that the 477 lb weight disadvantage of the trike may simply be enough to dull the throttle response improvement a bit. Despite the weight, the trike IS ifting the front end notably on the way to 60 mph when a lot of throttle is being applied.

Jim G

 

My bad Jim I got lost in your thread … I asked because I have never had a single issue related to any of your testing threads with any of my bikes … ever.

” The other 54 “ plus the 4 HD’s … 58 Bikes in 56 years? Lot of issues with a brood that size?

 

No issues because I mostly had them 1 or 2 at a time, although once in a while more than that (once I had 5, but that was very unusual). I enjoyed them all, each in its own unique way.

Most riders don't even relaize they have any issues. They just ride, and enjoy doing just that. But my Engineering Physics education coupled with my natural engineering nature always end up having me look deeper than most riders do, in both my motorcycles and my cars. I love analyzing and modifying them. It's what I do for fun, and now in retirement, I actually have enough time to do it.

Jim G

 

Jim,
Dont know if I’m in the right thread or not, but yes I’ll do the 91 deg F and possibly a 101 deg F too. Lol

Might not hit 100 deg F anymore this year. Is your Bluetooth HD tuner you speak of the Screaming Eagle Tuner? If so I might have one of those, it’s the new one.

It’s possible a lot of guys engines get to warm down here in the lower 48 because it is so much warmer, and don’t even realize it. With the temp gauge we will know the temperature.
Thanks
Mike

 

Yes, this is the correct thread, Mike. I would greatly appreciate your doing the 2 higher ambient temperature tests, as we really need those to have the whole story, and Heat has a strong negative efefct on me, so I try hard to avoid it.

Yes, it is the newest model of HD Screamin Eagle Bluetooth tuner I am using, so we do appear to have the exact same tuner, and also LED temperature gauge (mine is balc finish and yours is chrome).

Do you also have the Stage 1 hardware and tune? And, have you done the "Smart Tune" process yet? I have both the Stage 1 tune and the Smart Tune customization now.

By the way, my LED temp & level gauge, despite being "not for the trike models", actually has the "add oil" line at the correct elevation on the dipstick, AND also the oil level as delivered by my HD dealer in my RG3 is EXACTLY at the top of the "normal" range (i.e. just below the "too high" mark. Nevertheless, the gauge is currently telling me "Oil High". Maybe the oil level being that CLOSE to the "too high" mark is causing that.

Also by the way, do you want me to send you my Excel worksheet? You could then just rename it for each of the 2 higher ambient temperatures, and change the numbers to match what you find in physical testing. If you want me to do this, just send me your email address in a private message.

Jim G

 

I'm still traveling, with limited time on the forums.

However, I will mention a few things.

1. Every time you stop to take temp readings, you are cooling down significantly, especially the engine temp.
2. Your findings are not surprising at all.
3. You cannot do an apple to apple test with an ambient temp that is varying between 62 and 72. Any test has to have all variables stable...this means:
a. Ambient temp
b. Throttle position
c. Speed
d. Wind (cross-wind, headwind, tailwind) This is A BIG factor
e. what gear you're in
f. Temps need to be measured within 30 seconds or less of letting off the throttle from sustained speed, otherwise the numbers will be skewed. It is pretty amazing what just 1 minute of slowing down, and riding slower will do to change the temps.
There is more, but that gives some food for thought.

In my previous post I realized I did not mention...when an engine is optimized, the difference between oil temp and the temp sensor on the rear cylinder head, on a fully heat soaked M8, will be 30-40 degrees F.
On an engine that is from the factory, that is not the case. You have a good oil cooler on your RG3, but not such great air flow over the metal.

Also, mentioned in many of our videos...230F for the oil is what is normal, according to Harley...but it is not ideal. Ideal is 190-210F, as shown by thousands of tests on engines.

The vast majority of Harley's, for the last 25 years, simply cannot achieve that, however, with a little work, 230F is achievable....even in ambient temps of 80-100F.

Last thought...for your testing to yield useful results, ride at sustained speeds (65 mph or more) until you see your oil temp stop rising. Then you know you are fully warmed up.

Kevin

 

Thanks Kevin. And on the tank lift, Natalie reassured me that the plastic triangular piece that also attaches via the front tank bolt is flexible enough and robust enough to adapt to the presence of the tank lift piece.

Jim G

 

“Most riders don't even relaize they have any issues.”

Is that a fair statement. There’s not a person here riding that doesn’t hear or feel even the slightest change, a click, a knock, a soft feeling tire, the wind and anything else that might be an “issue”

Most riders here know exactly when they have an issue. I certainly do and I’m sure any experienced rider also would

 

Example of what I meant: A normal Harley comes with NO engine temperature gauge, and NO oil temperature gauge, so most HD riders have no wya of knowing that they may have an engine heat issue.

Jim G