Photo of PV today

[DK Custom Products]

A while back I did a couple of posts on the different readings that the PV can give on temps.

Today, on a ride, I put the cruise on and took a photo.

You can see on the infotainment that it was a warm day for us...depending on where I was it was fluctuating between 89 and 92.

On the PV-

Middle Left reading of 203 is the actual temperature of the back left side of the front cylinder head. This is a hard reading.

Upper Left of 258.80 is a calculated number, and algorithm derived number. This is calculated by the factory ECM using a variety of factors ( ET, MAP, Throttle position, IAT & more). This "fake" or calculated number is what the ECM uses to adjust the tune, including knock retard.

This number can be as much as 100 F higher than the ET number, or it can be very close to the same as the ET number. It all depends on a variety of conditions.

The condition when the photo was taken was a warm day, had been riding for about an hour, it was on cruise at 60 mph in 6th gear on level ground (yes, it was lugging a bit, as evidenced by the MAP reading on the center right and the spark knock on the lower right).

This calculated number moves very quickly, up and down, depending on conditions, whereas the ET number (which is a real number) moves much more slowly.

On my TG, at 75 mph on a warm day, it is not unusual to see the ET at 210 F and the upper left number at 300 f. If I slow down, exiting the interstate, the ET will not change, staying at 210, but the upper left number can drop to 225 in a matter of 15 seconds.

Upper right number is a real number, showing the temperature of the coolant.

Bottom left shows my MPG I was getting cruising the back roads between 45 and 65 today.

Kevin

 

[Fearless]

A while back I did a couple of posts on the different readings that the PV can give on temps.

Today, on a ride, I put the cruise on and took a photo.

You can see on the infotainment that it was a warm day for us...depending on where I was it was fluctuating between 89 and 92.

On the PV-

Middle Left reading of 203 is the actual temperature of the back left side of the front cylinder head. This is a hard reading.

Upper Left of 258.80 is a calculated number, and algorithm derived number. This is calculated by the factory ECM using a variety of factors ( ET, MAP, Throttle position, IAT & more). This "fake" or calculated number is what the ECM uses to adjust the tune, including knock retard.

This number can be as much as 100 F higher than the ET number, or it can be very close to the same as the ET number. It all depends on a variety of conditions.

The condition when the photo was taken was a warm day, had been riding for about an hour, it was on cruise at 60 mph in 6th gear on level ground (yes, it was lugging a bit, as evidenced by the MAP reading on the center right and the spark knock on the lower right).

This calculated number moves very quickly, up and down, depending on conditions, whereas the ET number (which is a real number) moves much more slowly.

On my TG, at 75 mph on a warm day, it is not unusual to see the ET at 210 F and the upper left number at 300 f. If I slow down, exiting the interstate, the ET will not change, staying at 210, but the upper left number can drop to 225 in a matter of 15 seconds.

Upper right number is a real number, showing the temperature of the coolant.

Bottom left shows my MPG I was getting cruising the back roads between 45 and 65 today.

Kevin

Great info Kevin you are running 15 to 20 degrees cooler than I am with Old Shiney. Bot sure how to get it cooler though I consistently run 225 to 230 Stop and go 242 to 248 any suggestions possibly go remote oil filter this winter any thoughts? :Shrug: ride safe Fred

 

[Jack Klarich]

Very good info

My PV reads under 300 ET now with Mighty Mites on even riding 2 up

Fred I think a remote oil filter would be a HUGE plus

Get 1 from Kevin

 

[DK Custom Products]

Great info Kevin you are running 15 to 20 degrees cooler than I am with Old Shiney. Bot sure how to get it cooler though I consistently run 225 to 230 Stop and go 242 to 248 any suggestions possibly go remote oil filter this winter any thoughts? :Shrug: ride safe Fred

Old Shiney is air cooled, and the one shown in the PV photo is Twin-Cooled. The differences in temps between those two different Twin Cams are:

Unique to the Twin-Cooled (air-cooled/liquid-cooled hybrid), also know aswaterheads or wetheads:​

The basics are the same on the Twin-Cooled as the Air-Cooled & Oil-Cooled, with the addition of the following:

1. They have higher compression, which creates more heat.
   
2. They Have slightly "hotter cams" which create more heat.
   
3. The water pump is in the location where Harley normally puts the oil cooler, resulting in NO oil cooler. So the oil and all portions of the engine, except for the liquid cooled heads, are even Hotter on the Twin-Cooled engines than the air-cooled.
   

Bottom line is the TC & M8 Twin-Cooled has Twin Problems

• While the heads are cooler, the rest of the engine is hotter.
  
• The oil gets hotter with no oil cooler to dissipate the heat.
  

All things being equal, the Twin-Cooled ET will run 20 or so degrees cooler than an air cooled.

All things being equal, the Twin-Cooled oil temps will run about 10 degrees warmer than an air cooled.

That said, if you are seeing your oil temps match or ET temps, you are good.

If your oil temps are running warmer than your ET temps, then a oil filter relocation will help, and adding a secondary oil cooler like this ONE, and/or replacing the factory oil cooler with one that works better, like this ONE, will bring down your oil temps and overall engine temps.

The ideal balance on an air cooled, for engine longevity, engine performance, and mpg, is to have the ET and oil temps be within a few degrees of each other.

Kevin