2024 Touring VVT Engines, 117, 121, 121 HO
#1
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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
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
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Top Answer
01-27-2024, 09:33 AM
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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.
#2
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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.
__________________
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Jamie Long / Fuel Moto USA
The USA's Leader V-Twin EFI & Performance www.fuelmotousa.com
Contact 920-423-3309
Email jamie@fuelmotousa.com
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Jamie Long / Fuel Moto USA
The USA's Leader V-Twin EFI & Performance www.fuelmotousa.com
Contact 920-423-3309
Email jamie@fuelmotousa.com
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#3
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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.
Last edited by HVYMTL1; 01-27-2024 at 09:50 AM.
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#4
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https://www.hdforums.com/forum/2014-...l#post21541561
Shows the various engines and their rated outputs
Shows the various engines and their rated outputs
#5
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https://www.hdforums.com/forum/2014-...l#post21541561
Shows the various engines and their rated outputs
Shows the various engines and their rated outputs
#6
#7
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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.
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Trending Topics
#8
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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!
Last edited by Beartooth Rider; 04-13-2024 at 12:41 PM.
#9
#10
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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!
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!
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