2023 Harley-Davidson CVO 121 Cu. In,

[Ohio HD]

I hadn't seen anyone post the 121 CVO motor specs. Below are the more pertinent specs.

Type: Milwaukee Eight 121 Cu. In. With VVT
Bore: 4.075"
Stroke: 4.625"
Max torque: 139 ft.lbs. @ 3000 rpm
Max HP: 115 horsepower @ 4500 rpm
Throttle body: 58mm
Static compression: 11.4:1
Cooling: Air, liquid, and oil cooling

So we now have an EPA compliant motor with .95 HP per cubic inch. Not bad for a smog motor.

That 4.625" stroke has me excited. I wonder how large of a bore they can fit with that stroke and new compression height of the pistons.

Anyone planning on going to the 120th shin dig? I assume that they'll have these on hand to demo ride them. I bet they feel strong for a stock HD.

[Hilly13]

I'm really interested to see what August brings, a Roadking Special with a 121 VVT engine would be awesome 😎

[boooby1744]

I think that motor will be exclusive to the CVO.However I'm guessin the VVT tech will be applied to the rest of the line and hopefully a 2024 RK Standard.

[Hilly13]

Yeah I dunno, it's not exactly the same engine as the 117m8, time will tell.

[tolobill]

Hey, they is a you tube video out that sows and explains hoe the VVT works and the cooling system.

[Coyote]

Hey, they is a you tube video out that sows and explains hoe the VVT works and the cooling system.

https://harleytechtalk.com/htt/index.php/topic,119665.0.html

[hrdtail78]

Heads are very interesting.  I assume they retrofit.

[Hilly13]

Must be something wrong with me, I'm looking at that intake opening and wanting to tidy it up 😂

[FLSTFIDave]

I hadn't seen anyone post the 121 CVO motor specs. Below are the more pertinent specs.

Type: Milwaukee Eight 121 Cu. In. With VVT
Bore: 4.075"
Stroke: 4.625"
Max torque: 139 ft.lbs. @ 3000 rpm
Max HP: 115 horsepower @ 4500 rpm
Throttle body: 58mm
Static compression: 11.4:1
Cooling: Air, liquid, and oil cooling

So we now have an EPA compliant motor with .95 HP per cubic inch. Not bad for a smog motor.

That 4.625" stroke has me excited. I wonder how large of a bore they can fit with that stroke and new compression height of the pistons.

Anyone planning on going to the 120th shin dig? I assume that they'll have these on hand to demo ride them. I bet they feel strong for a stock HD.

Isn't that the same stroke as the 135" motor Harley has?  So 135" should be no problem.  I would think Harley  will have a 135 kit for this like the have the 131 for the 117.

[rigidthumper]

135 will be the drop on kit for the 121 "Center Cooled" engines, but no SE map yet.

[ziggy24]

I hadn't seen anyone post the 121 CVO motor specs. Below are the more pertinent specs.

Type: Milwaukee Eight 121 Cu. In. With VVT
Bore: 4.075"
Stroke: 4.625"
Max torque: 139 ft.lbs. @ 3000 rpm
Max HP: 115 horsepower @ 4500 rpm
Throttle body: 58mm
Static compression: 11.4:1
Cooling: Air, liquid, and oil cooling

So we now have an EPA compliant motor with .95 HP per cubic inch. Not bad for a smog motor.

That 4.625" stroke has me excited. I wonder how large of a bore they can fit with that stroke and new compression height of the pistons.

Anyone planning on going to the 120th shin dig? I assume that they'll have these on hand to demo ride them. I bet they feel strong for a stock HD.

I am guessing these numbers are at the crank?!

[Coyote]

I hadn't seen anyone post the 121 CVO motor specs. Below are the more pertinent specs.

Type: Milwaukee Eight 121 Cu. In. With VVT
Bore: 4.075"
Stroke: 4.625"
Max torque: 139 ft.lbs. @ 3000 rpm
Max HP: 115 horsepower @ 4500 rpm
Throttle body: 58mm
Static compression: 11.4:1
Cooling: Air, liquid, and oil cooling

So we now have an EPA compliant motor with .95 HP per cubic inch. Not bad for a smog motor.

That 4.625" stroke has me excited. I wonder how large of a bore they can fit with that stroke and new compression height of the pistons.

Anyone planning on going to the 120th shin dig? I assume that they'll have these on hand to demo ride them. I bet they feel strong for a stock HD.

I am guessing these numbers are at the crank?!

I'd think not.

[FLDavetrain]

I hadn't seen anyone post the 121 CVO motor specs. Below are the more pertinent specs.

Type: Milwaukee Eight 121 Cu. In. With VVT
Bore: 4.075"
Stroke: 4.625"
Max torque: 139 ft.lbs. @ 3000 rpm
Max HP: 115 horsepower @ 4500 rpm
Throttle body: 58mm
Static compression: 11.4:1
Cooling: Air, liquid, and oil cooling

So we now have an EPA compliant motor with .95 HP per cubic inch. Not bad for a smog motor.

That 4.625" stroke has me excited. I wonder how large of a bore they can fit with that stroke and new compression height of the pistons.

Anyone planning on going to the 120th shin dig? I assume that they'll have these on hand to demo ride them. I bet they feel strong for a stock HD.

I am guessing these numbers are at the crank?!

I'd think not.

Yes, they are

[rigidthumper]

SAE J1349 (torque testing method) assumes 85% drive train efficiency.

[hrdtail78]

Here is the intake manifold.

You cannot view this attachment.

[Ohio HD]

I'm sure that all of the aftermarket performance businesses are looking towards what they can do with the new 121 VVT motor. Feuling seems to be in high gear working towards products for these motors. This short video gives some highlights of what they're working on. It also looks like hrdtail78's assumption of retrofit on the heads is correct.

Some really exciting times are ahead I think for the M8 motor.

[FLSTFIDave]

Feuling seems to be in high gear working towards products for these motors. This short video gives some highlights of what they're working on. It also looks like hrdtail78's assumption of retrofit on the heads is correct.

Some really exciting times are ahead I think for the M8 motor.

The new M8 VVT is  very nice motor.  I have just over 1800 miles on it. I wanted to do what I always do with the CVO bikes, Fullsac Baffles because they work and sound good and you can keep the good looking stock exhaust.  At this point Steve is not making the Fullsac baffles for it, because instead of 2 tack welds holding the baffle in, Harley now welds the circumference.  That said his excellent M8 head pipe bolts right up.

The motor in the real world performs very well.  Same valve train noise as the regular M8 and video showed why.  Motor pulls good, and is smooth. You can feel the difference between rain, road and sport modes.  On motor side its throttle response and compression braking changes, so I am speculating it changes cam timing a little.

Being this motor has same stroke as the 135, will HD have a 135 Kit for it?  They have the cylinders, pistons, intake and so on for it.

You cannot view this attachment.

[rigidthumper]

No ECM mapping at the moment for anything other than "121" Center cooled Stage 1" on the VVT models. The 135 cylinders and pistons are a bolt on, but no tuning device or tunes exist as of right now.

[HogMike]

Feuling seems to be in high gear working towards products for these motors. This short video gives some highlights of what they're working on. It also looks like hrdtail78's assumption of retrofit on the heads is correct.

Some really exciting times are ahead I think for the M8 motor.

The new M8 VVT is  very nice motor.  I have just over 1800 miles on it. I wanted to do what I always do with the CVO bikes, Fullsac Baffles because they work and sound good and you can keep the good looking stock exhaust.  At this point Steve is not making the Fullsac baffles for it, because instead of 2 tack welds holding the baffle in, Harley now welds the circumference.  That said his excellent M8 head pipe bolts right up.

The motor in the real world performs very well.  Same valve train noise as the regular M8 and video showed why.  Motor pulls good, and is smooth. You can feel the difference between rain, road and sport modes.  On motor side its throttle response and compression braking changes, so I am speculating it changes cam timing a little.

Being this motor has same stroke as the 135, will HD have a 135 Kit for it?  They have the cylinders, pistons, intake and so on for it.

You cannot view this attachment.

If your head pipe is the same, you should be able to use the cvo mufflers from earlier m8 bikes.

I used my 2017 cvo mufflers on my 2019 and my riding buddy has those same mufflers on his 2021. 

[FLSTFIDave]

No ECM mapping at the moment for anything other than "121" Center cooled Stage 1" on the VVT models. The 135 cylinders and pistons are a bolt on, but no tuning device or tunes exist as of right now.

I understand this.  Harley already has a tuner for this bike.  What they need is an EPA compliant map for this bike as a 135.

[FLSTFIDave]

If your head pipe is the same, you should be able to use the cvo mufflers from earlier m8 bikes.

I used my 2017 cvo mufflers on my 2019 and my riding buddy has those same mufflers on his 2021. 

True.  I have no more CVO mufflers from the M8 left.  They went with my 19 I traded.  I have asked friends who have had M8 CVO's none have any.  My friends on CVO's mostly like me, went the Fullsac route.

[HogMike]

If your head pipe is the same, you should be able to use the cvo mufflers from earlier m8 bikes.

I used my 2017 cvo mufflers on my 2019 and my riding buddy has those same mufflers on his 2021. 

True.  I have no more CVO mufflers from the M8 left.  They went with my 19 I traded.  I have asked friends who have had M8 CVO's none have any.  My friends on CVO's mostly like me, went the Fullsac route.

IIRC
The 2023 cvo muffler is a little larger OD than last year's model?
I'll bet Steve is working on a solution for the new ones. It just takes a little time to get everything done and on the dyno.

It will be interesting to see what the new motor will produce with the Harley "stage kits" as they roll out!

I'll keep my 124. 😁

[FLSTFIDave]

If your head pipe is the same, you should be able to use the cvo mufflers from earlier m8 bikes.

I used my 2017 cvo mufflers on my 2019 and my riding buddy has those same mufflers on his 2021. 

True.  I have no more CVO mufflers from the M8 left.  They went with my 19 I traded.  I have asked friends who have had M8 CVO's none have any.  My friends on CVO's mostly like me, went the Fullsac route.

IIRC
The 2023 cvo muffler is a little larger OD than last year's model?
I'll bet Steve is working on a solution for the new ones. It just takes a little time to get everything done and on the dyno.

It will be interesting to see what the new motor will produce with the Harley "stage kits" as they roll out!

I'll keep my 124. 😁

Muffler is 4.5" instead of 4".  Baffle is now welded in, the entire circumference, instead of two tack welds like past CVO's.  I have talked to  Steve, he is trying to figure out if a tool can be made so customers can get baffle out with out destroying the muffler.

Steve's Fullsac head pipe fits just fine.

[ziggy24]

Here is the intake manifold.

You cannot view this attachment.

Interesting that they dumped the plastic manifold.

[HogMike]

If your head pipe is the same, you should be able to use the cvo mufflers from earlier m8 bikes.

I used my 2017 cvo mufflers on my 2019 and my riding buddy has those same mufflers on his 2021. 

True.  I have no more CVO mufflers from the M8 left.  They went with my 19 I traded.  I have asked friends who have had M8 CVO's none have any.  My friends on CVO's mostly like me, went the Fullsac route.

IIRC
The 2023 cvo muffler is a little larger OD than last year's model?
I'll bet Steve is working on a solution for the new ones. It just takes a little time to get everything done and on the dyno.

It will be interesting to see what the new motor will produce with the Harley "stage kits" as they roll out!

I'll keep my 124. 😁

Muffler is 4.5" instead of 4".  Baffle is now welded in, the entire circumference, instead of two tack welds like past CVO's.  I have talked to  Steve, he is trying to figure out if a tool can be made so customers can get baffle out with out destroying the muffler.

Steve's Fullsac head pipe fits just fine.

👍👍

[FLSTFIDave]

Here is the intake manifold.

You cannot view this attachment.

Interesting that they dumped the plastic manifold.

The shape change is also interesting.  Obviously the intake on the heads also changed. 

[Ohio HD]

Here is the intake manifold.

You cannot view this attachment.

Interesting that they dumped the plastic manifold.

I would say they did that due to the non-round port connection. That elliptical shape would most likely not seal well made from plastic. A round shape nade from plastic will resist collapsing under pressure from the intake seal and flange. An elliptical shape will

Here is the intake manifold.

You cannot view this attachment.

Interesting that they dumped the plastic manifold.

A plastic version with the elliptical shape would fail faster than the round plastic manifold does.

[Ohio HD]

Another video released from Feuling regarding the 121 CVO motor. I hadn't heard it mentioned until I saw this video, HD removed the head breathers completely and are venting through the transmission housing and then back to the TB air breather. They didn't go into any details as to what type of valving is used in the new venting system.

[FLSTFIDave]

Thank you for posting that video.   I was curious about that line to back of Air Cleaner when I changed out mine to the Extreme Heavy Breather. Nice they are using a better head gasket now.

I'll roll over 5000 miles on mine today, its at 4983 right now.

[Ohio HD]

I thought this was a significant bit of info from V Twin Powersports. They've used an aftermarket ECU from Rusefi on a 2023 CVO 121VVT. According to what they said, the new ECU, no RPM limiter, no traction control, no speed limiter, and no air box on the bike. Other than that all stock including exhaust.

Pretty impressive. And I think they as well as others will possibly find more in them as tuning tools progress for this motor.

V Twin Powersports 2023 CVO 121VVT

[Ohio HD]

They added a D&D system, a few more ponies came out.

[FLSTFIDave]

That is pretty impressive for just tuning, albeit by a new ECU.  Adding a good pipe sure helps this tune. Great torque curve.  I would like to see what Power Vision and TTS accomplish tuning this and keeping traction control and the other rider aids, but removing rev limiter and speed limiter.

[rigidthumper]

It'll be a while before anybody gets access to the factory ECM. HD went to great lengths to prevent tuning access- that's why Mark went with a non-factory ECM. As of right now, he is the only game in town.

[IronButt70]

It'll be a while before anybody gets access to the factory ECM. HD went to great lengths to prevent tuning access- that's why Mark went with a non-factory ECM. As of right now, he is the only game in town.

Guessing factory ECM has 256 bit encryption. Will take time to crack if it does.

[rigidthumper]

They have a dual can bus protocol with air gap flashing, in addition to the normal encryption. The race teams are not even using the new system.

[hrdtail78]

I saw somebody posted some blank cams for VVT.  Now a tuning strategy.

[Ohio HD]

That should start making for some lively times. I imagine the tuning process will be somewhat complex, or at least add time to the tuning session.

[hrdtail78]

I don't think we will get control over valve timing.  We might get an ignition trim table based on cam position.  BUT I would bet that cam advancement at 100kpa is predicable.

[Ohio HD]

If I follow the VVT operation, the shift in cam timing is either, here or is there, and not variable. Is that how the system works? 

I guess I should have written this as the cam timing is variable, just that it has a fixed advance and retard position, and not anywhere in between. At least that's how I understand it.

[FLSTFIDave]

Not sure on how timing actually is achieved.  That said I know that both Fueling and S&S are both working on cams for the VVT 121.

Looks like H-D is planning on VVT for the future and the New body style Road Glide and Street Glide and CVO ST have the same timer cover as the VVT 121.

[rigidthumper]

The cam covers look the same, but they are not- the 117RG/SG & 121ST use the 25701666 cover, and only get a cam prox sensor (32700162), where the CVORG & SG 121VVT uses the 25701485 cover, gets that same cam prox sensor, and a VVT Cam actuator solenoid (31500034).
Data found here & here.

[Buglet]

   Looks like they use the same engine cases for ST and VVT 121. But a different number for the 117 I would say it's the same cases just the color is the reason for the different part number. I think this will give you the option to go either way.   

[boooby1744]

All 2024's have the same primary gearing and 2.87 final drive.
The Road Glide ST has a 3.06 final drive...

[wfolarry]

If you want to see some flow #'s
https://www.facebook.com/permalink.php?story_fbid=pfbid02XyvAfXiYCkXKjWr5qVRd91g13gn3AKyVVxFpArLsbx7SNK7DUek8NT8xCnSYn1R6l&id=100063488652744

[wfolarry]

Here it is on the flow bench
https://www.facebook.com/100063488652744/videos/521062117041067