I haven't seen any of these in person yet. However, the online images show VVT cam chest covers, which I found interesting, so I looked up cam chest parts, and they do list VVT parts but use different cams.
Performance descriptions for three RG models.

2024 Road Glide
NEW MILWAUKEE-EIGHTŪ 117 V-TWIN ENGINE
With increased displacement, torque, and horsepower, the 2024 engine features new liquid-cooled cylinder heads that further optimize thermal comfort for the rider, especially in low-speed riding situations and hot weather.

2024 CVO Road Glide
MILWAUKEE-EIGHTŪ VVT 121 V-TWIN ENGINE
The highest displacement powertrain ever to be factory-installed on a Harley-Davidson Touring motorcycle, the Milwaukee-Eight VVT 121 engine features liquid-cooled cylinder heads, variable valve timing (VVT), and a new intake tract. The increased displacement produces more power and torque than the Milwaukee-Eight 117 engine, while VVT broadens the overall powerband and improves fuel economy.

2024 CVO Road Glide ST
MILWAUKEE-EIGHTŪ 121 HO V-TWIN ENGINE
The Milwaukee-Eight 121 High Output (HO) engine is tuned to produce more horsepower and torque than the Milwaukee-Eight VVT 121 engine with a high-performance camshaft, race-inspired high-performance air intake, and elevated 5,900 RPM redline.

Interesting that HD doesn't specifically mention VVT for all three, and RG/Ultra Limited bikes only get 114 engines, but HD marketing is what it is.

Compared to last year's 121 VVT, the ST power gains aren't bad for an EPA compliant cam, intake, and mufflers.
The ST also has slightly lower overall gearing (different transmission sprocket/belt) for the acceleration enthusiasts!

PRIMARY DRIVE
Chain, 34/46 ratio
GEAR RATIOS (OVERALL) 1ST
10.233
GEAR RATIOS (OVERALL) 2ND
7.093
GEAR RATIOS (OVERALL) 3RD
5.268
GEAR RATIOS (OVERALL) 4TH
4.266
GEAR RATIOS (OVERALL) 5TH
3.635
GEAR RATIOS (OVERALL) 6TH
3.067

 

The 117 (Street Glide & Road Glide) and 121 HO (Road Glide CVO ST) engines do not have VVT. The only Touring models with VVT are the CVO Street Glide and CVO Road Glide. The non VVT 117/121 engines have a new cam cover (like the VVT models) as these engines also have a cam proximity sensor.

 

Even better! For myself, anyway, I did miss the lack of a VVT actuator solenoid in the parts call out earlier on two out of three. But I replace enough VVT solenoids and related things on our work fleet that I won't miss replacing them on a possible future purchase. Thanks for the clarification.

 

https://www.hdforums.com/forum/2014-...l#post21541561

Shows the various engines and their rated outputs

 

Motorhead, I am for not wandering into other forums and seeing that. Have you had a chance to dissect the CVO RG ST tune? Just wondering how different the tuning will be compared to the VVT version. However, my track record for finding a dyno tuner in my area that can tune one of my builds for an enjoyable ride and still live truly sucks.

 

What is difference between the 2018 117 and the 2024 117.

 

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.

 

I saw an interesting video where they measured the cylinder head temperatures and oil tank temperatures on both twin cooled and oil cooled touring models then compared the two models. No surprise, the twin cooled had the coolest cylinder head temperatures as expected. The epiphany for me was that the twin cooled had a significantly elevated oil tank temperature since it does not have an oil cooler like the oil cooled models.

Now I'm wondering if an auxiliary oil cooler might be a clever strategy for heat mitigation on twin cooled models. Of course there would be an extra load on the oil pump, but it should be able to circulate the oil a little further through an oil cooler.

Opinions Please, clever ideas sometimes need a second thought!

 

What is twin cooled? I have an M8 with oil cooled heads. Sump engine oil temp stays right around 200 degrees F, as measured via dipstick temp gauge = perfect.

 

Twin Cooled been around for years and I don't ever recall hearing reports of oil related engine problems .. I don't have any concerns and have gone back to HD 360 conventional oil on my 24 with complete faith and trust in its ability to perform its intended purpose, protecting my engine from excessive wear or damage ... its proven itself successful over a couple decades now even in earlier Softails that didn't even have oil coolers ... I'm just going to continue to enjoy riding tens of thousands of worry free miles as I always have without fail