Twin Cooled is the term the MoCo uses to refer to their engines on Touring bikes that feature a basic liquid cooling system with a coolant pump and a radiator circulating the coolant around the cylinder heads to cool the motor.

 

Thank you for sharing your opinion and I do respect it. I'm currently riding an oil cooled 124 running 11.1 compression and a big cam and it gets hot! Using Syn 3, I usually start feeling guilty after three to four thousand miles because the way it looks and smells.

After watching the video, my assumption was the oil in Twin Cooled oil tank would be hotter than the oil in Oil Cooled oil tank. I realize the new cooling system is going to circulate the coolant from the rear cylinder to the front cylinder and it just seemed like the oil might need a little cooling.

I thought it was interesting that the cylinder temperatures remained the same on both bikes.

Like you, I will just enjoy the ride.

 

I would just ask myself, who would be in the best position to understand and determine if that was really needed? obviously that would be the MOCO..they above all others know that they build hot running engines after over a century of doing so and design, test, produce, dissect failures and responsible to provide powertrain warranties...I'd just give them the benefit of the doubt that oil coolers are unnecessary on Twin Cooled engines .. I'm still very surprised out how I am not feeling any heat from my 117 after over 4000 miles and plenty of recent rides in mid and upper 70s .. my previous twin cams and M8s put off a lot of felt heat

 

Thanks again got sharing and I'm just looking forward to riding the new 121HO!

 

that oughta' be a kick in the @$$ !!!

 

I'll let you know!

 

[QUOTE=mjwebb;21643626]

Same Name, More Power

The Milwaukee-Eight 117 might sound like a familiar name, but this one’s updated inside to make more power than before. For 2024, that thrust is ramped up a little more thanks to the new-and-improved Milwaukee-Eight 117. Despite the name, this is not the same as the 2023 M8 117s, as the new bike makes 3% more power (105 hp) and 4% more torque (130 lb-ft). Shoving more air into the engine is the basis for this power bump, and credit here goes to the new airbox and air filter for the 117. With a capacity of 4.0 liters, the new airbox is more than 50% bigger than the 107/114 engines with the Heavy Breather intakes. Molded within the airbox is a new intake design that’s smoother, with less harsh bends for the air to travel around. The throttle body itself is bigger, at 58mm compared to 55mm on the 2023 M8 117 engines. Handling the larger income of air are redesigned cylinder heads with oval intake ports and low-profile intake valve seats for more intake air velocity and tumble. Combined with the deeper spark plugs and a different squish band, the air-fuel ratio now gets squeezed even tighter as compression ratio has gone up a point to 10.3:1 (from 10.2:1). The sum change creates more turbulence for a more powerful explosion once the spark plug ignites.

Of course, more power creates more heat, and this is where the new cooling system comes in. The new-and-improved liquid-cooled heads (NOT a liquid-cooled engine, as Harley stressed to us) focuses the coolant flow to the rear cylinder head first, as it gets less air flow and is thus hotter. Coolant then moves to the front cylinder before heading back to the radiator. Cleverly, the cooling fan on the radiator directs air flow underneath the bike so it’s not hitting the rider or passenger.[/QUOTE

Have an issue with them cooling system NOT running and overheating. The bike runs great but that little red light keeps looking at me.
what is potential for engine damage?
Have taken it to dealer and it keeps coming back. Thinking bad relay but I got no codes, can force fan on with engine off and the pump runs as well...

 

I think HD did it to reduce heat discomfort for riders. Which it does well. Probably not really necessary otherwise. Although in cooler fall riding I did sometimes enjoy the heat from the engine radiating up at slower in town speeds and stops.