CMB 21 VAC

[Nigtmare]

Has anyone tried this engine yet???? how is the P/L fit.

I want to get a new engine for my JAE and dont't know whether to get the new CMB or the 35 plus N/R???

Thanks. Nick

 

[DaveMarles]

Way better than any previous valvola. Massive improvement in torque and drivability.

Dave

 

[Stuart Barr]

Mark Grim has tested the proto type 21VAC recently and he has said the same as Dave. It pulled all 21 props with authority. This motor should be in stock in 3-4 weeks.

Stu Barr

 

[WIDEBOY]

Nic

Check out the Hydro section on here with the JAE 21 with a Novarossi or try an A/A.

 

[Duck899]

Has anyone tried this engine yet???? how is the P/L fit.

I want to get a new engine for my JAE and dont't know whether to get the new CMB or the 35 plus N/R???

Thanks. Nick

N/R or A/A

 

[Rokieboater]

Mark Grim has tested the proto type 21VAC recently and he has said the same as Dave. It pulled all 21 props with authority. This motor should be in stock in 3-4 weeks.

Stu Barr

Was Grim's stock or typical Grim worked?????

Robert

 

[Richard Dahlheimer]

Mark Grim has tested the proto type 21VAC recently and he has said the same as Dave. It pulled all 21 props with authority. This motor should be in stock in 3-4 weeks.

Stu Barr

Was Grim's stock or typical Grim worked?????

Robert

Hello Nick, the piston and sleeve fit on mine is very good, but do to hard water i can not post any test results. Mine is prepped by Steve Wood, and i am very anxious to try it. Richard D

 

[Stuart Barr]

Robert,

I asked him to evaluate this motor in stock form and he did.

 

[Nigtmare]

Hey Stu what are the timing # like? and what type of a boat was the engine evaluate @ .

Thanks. Nick

 

[Nigtmare]

Nic

Check out the Hydro section on here with the JAE 21 with a Novarossi or try an A/A.

Hey Steve I saw the video and that is with the N/R flash...... I will never pay what those engines sell for I been running CMB engines for a while now but I had a bad experiences with the CBM 21 06/07 model that has left a bad taste in my mouth :lol: I have 3 CMB's 45/s and a 67 that are tanked with no problems..

I know nothing about the AA engines :unsure:

Nick

 

[Duck899]

Nic

Check out the Hydro section on here with the JAE 21 with a Novarossi or try an A/A.

Hey Steve I saw the video and that is with the N/R flash...... I will never pay what those engines sell for

I been running CMB engines for a while now but I had a bad experiences with the CBM 21 06/07 model that has left a bad taste in my mouth

I have 3 CMB's 45/s and a 67 that are tanked with no problems..

I know nothing about the AA engines

Nick

The A/A engines are being built by Rossi for Al Hobbs with mod recommendations that are done at the factory. The mods are things done by a couple of guys who run JAE 21's....so, essentially you get a hopped up stock engine.

 

[Nigtmare]

Mark Grim has tested the proto type 21VAC recently and he has said the same as Dave. It pulled all 21 props with authority. This motor should be in stock in 3-4 weeks.

Stu Barr

Was Grim's stock or typical Grim worked?????

Robert

Hello Nick, the piston and sleeve fit on mine is very good, but do to hard water i can not post any test results. Mine is prepped by Steve Wood, and i am very anxious to try it. Richard D

where did you get the engine from Richard??

Thanks. Nick

 

[DaveMarles]

I was asked to test the CMB 21 stock which I did. After a little run time it had outstanding power through the corners and it would throttle down to very low rpm on the water and pull away every time without struggling. ABC set is the same as last years motor and induction was 149/55. I later modded mine to my usual specs and bored the carb to 9.5mm and still the same outstanding torque and throttling. Unlike any 21 engine I've ever come across. This is going to make running a 21 motor a walk in the park. I've converted 2 of my greenhead motors to the new drum and carb assembly and the same kind of improvement was there. I figure it has to be something to with the fact that the conrod is not obstructing the induction port but that's only a theory

Dave

 

[larcor69]

glad I am hearing good thing's with this engine, cant wait to run mine!!

 

[Nigtmare]

I was asked to test the CMB 21 stock which I did. After a little run time it had outstanding power through the corners and it would throttle down to very low rpm on the water and pull away every time without struggling. ABC set is the same as last years motor and induction was 149/55. I later modded mine to my usual specs and bored the carb to 9.5mm and still the same outstanding torque and throttling. Unlike any 21 engine I've ever come across. This is going to make running a 21 motor a walk in the park. I've converted 2 of my greenhead motors to the new drum and carb assembly and the same kind of improvement was there. I figure it has to be something to with the fact that the conrod is not obstructing the induction port but that's only a theory

Dave

Dave dont't they have a different type of a crank also? was it any gains from the mods at all?

Nick

 

[DaveMarles]

I was asked to test the CMB 21 stock which I did. After a little run time it had outstanding power through the corners and it would throttle down to very low rpm on the water and pull away every time without struggling. ABC set is the same as last years motor and induction was 149/55. I later modded mine to my usual specs and bored the carb to 9.5mm and still the same outstanding torque and throttling. Unlike any 21 engine I've ever come across. This is going to make running a 21 motor a walk in the park. I've converted 2 of my greenhead motors to the new drum and carb assembly and the same kind of improvement was there. I figure it has to be something to with the fact that the conrod is not obstructing the induction port but that's only a theory

Dave

Dave dont't they have a different type of a crank also? was it any gains from the mods at all?

Nick

I didnt use the crank with balance weights. The modded motor performed much better but lost none of the tractability and throttling.

Dave

 

[dwilfong]

I was asked to test the CMB 21 stock which I did. After a little run time it had outstanding power through the corners and it would throttle down to very low rpm on the water and pull away every time without struggling. ABC set is the same as last years motor and induction was 149/55. I later modded mine to my usual specs and bored the carb to 9.5mm and still the same outstanding torque and throttling. Unlike any 21 engine I've ever come across. This is going to make running a 21 motor a walk in the park. I've converted 2 of my greenhead motors to the new drum and carb assembly and the same kind of improvement was there. I figure it has to be something to with the fact that the conrod is not obstructing the induction port but that's only a theory

Dave

Dave dont't they have a different type of a crank also? was it any gains from the mods at all?

Nick

I didnt use the crank with balance weights. The modded motor performed much better but lost none of the tractability and throttling.

Dave

Dave

I was told that the boost port is larger in the new sleeve. I have an old small case MAC will this new sleeve work in the old case.

David

 

[Richard Dahlheimer]

Hello Nick, i bought my Evo .21 from Steve Wood. Great service and great man to deal with. Steve is a CMB dealer also. 319-752-4482 Richard D

 

[ids987]

I was asked to test the CMB 21 stock which I did. After a little run time it had outstanding power through the corners and it would throttle down to very low rpm on the water and pull away every time without struggling. ABC set is the same as last years motor and induction was 149/55. I later modded mine to my usual specs and bored the carb to 9.5mm and still the same outstanding torque and throttling. Unlike any 21 engine I've ever come across. This is going to make running a 21 motor a walk in the park. I've converted 2 of my greenhead motors to the new drum and carb assembly and the same kind of improvement was there. I figure it has to be something to with the fact that the conrod is not obstructing the induction port but that's only a theory

Dave

Dave,

Do you think that the improvement in torque, could be partly due to improved pumping - smaller case volume etc ?

Ian

 

[DaveMarles]

I was asked to test the CMB 21 stock which I did. After a little run time it had outstanding power through the corners and it would throttle down to very low rpm on the water and pull away every time without struggling. ABC set is the same as last years motor and induction was 149/55. I later modded mine to my usual specs and bored the carb to 9.5mm and still the same outstanding torque and throttling. Unlike any 21 engine I've ever come across. This is going to make running a 21 motor a walk in the park. I've converted 2 of my greenhead motors to the new drum and carb assembly and the same kind of improvement was there. I figure it has to be something to with the fact that the conrod is not obstructing the induction port but that's only a theory

Dave

Dave,

Do you think that the improvement in torque, could be partly due to improved pumping - smaller case volume etc ?

Ian

Ian, It doesn't have a smaller case volume.