CMB 21RS vs. Nova Rossi SXM?

[Terry Keeley]

Looking to re-engine my little Speedmaster and am down to the above choices, been running Nova 2000's (SS) and am very happy with them but my parts inventory is getting low.

I really don't like that 25.4mm rear bearing on the Nova that's only available from them at $50, heard the race's can crack too.

Also heard through the grapevine that the 2514 rear bearing on the CMB can wear out quick, anyone else experience this?

Any other points? :blink:

 

[Walt Barney]

Terry,

I just put new bearings in my Nova Rossi and the the set was not even 40.00. From Boca Brgs.

Walt Barney

 

[carlnoki]

Terry;

been running a 21rs in my little girls speedmaster 20 since last season. still on original bearings. runs great.

carl cisneros

 

[Terry Keeley]

Terry,

I just put new bearings in my Nova Rossi and the the set was not even 40.00. From Boca Brgs.

Walt Barney

Hey Walt:

Is that the long stroke model with the 25.4mm rear bearing? Thought it was only avail from NR at $50. :blink:

Terry;

been running a 21rs in my little girls speedmaster 20 since last season. still on original bearings. runs great.

carl cisneros

Thanks!

 

[F.Orlic]

Novarossi bearings are much higher quality than 10 years ago, are they overpriced you bet, however when bearing last 10-12 gl running hard that is good enough for me. Terry, you have seen my engines run, I run them hard with only 6% oil and no bearing failure. Only bearing that failed (to the best of my knowledge) were Boca or bearings refitted with wrong ceramic balls.

In my experience main cause of bearing failures was fuel with poor quality oil. This is less of a problem with bigger engines which can run just fine with poor quality oil as long as there is a lot of it.

 

[Terry Keeley]

Thanks for the input Franco, and yes I've seen your NR's, they smoke!

I just can't seem to get around that rear bearing thing, also heard parts are getting harder to find, is that true?

 

[Marty Davis]

Thanks for the input Franco, and yes I've seen your NR's, they smoke!

I just can't seem to get around that rear bearing thing, also heard parts are getting harder to find, is that true?

Terry:

As good as the engine that you have been running runs, I can't imagine why you would change it.

Marty Davis

 

[AndyBrown]

Terry,

The newest CMB's are using 13 mm bearings. They are cheap, but they don't last long. So you won't save anything in the long run.

I would stick with Novarossi before I paid big money new CMB RS 21.

The MAC buggy engine is almost identical to the RS. The RS porting is almost an exact copy of the MAC buggy porting.

I'm selling those engine cheap...you could get two for the price of an RS and I will have parts for a long time to come.

If you decide to stick with Novarossi, don't forget, There are tons of parts availible through the car market outlets.

 

[john22469]

Andy

do i understand you correct that we can get parts for a short stroke nova rossi marine from the car guys. i have two short stroke nova that i need piston and sleeves.

 

[Terry Keeley]

Thanks for the input Franco, and yes I've seen your NR's, they smoke!

I just can't seem to get around that rear bearing thing, also heard parts are getting harder to find, is that true?

Terry:

As good as the engine that you have been running runs, I can't imagine why you would change it.

Marty Davis

Ya, I know, thanks...

Pretty impressed with the 45 & 67 CMB's I've been running and was wondering is the 21 is as good?

Terry,

The newest CMB's are using 13 mm bearings. They are cheap, but they don't last long. So you won't save anything in the long run.

I would stick with Novarossi before I paid big money new CMB RS 21.

The MAC buggy engine is almost identical to the RS. The RS porting is almost an exact copy of the MAC buggy porting.

I'm selling those engine cheap...you could get two for the price of an RS and I will have parts for a long time to come.

If you decide to stick with Novarossi, don't forget, There are tons of parts availible through the car market outlets.

Thanks for the input Andy, well taken!

 

[Walt Barney]

Terry,

I just put new bearings in my Nova Rossi and the the set was not even 40.00. From Boca Brgs.

Walt Barney

Hey Walt:

Is that the long stroke model with the 25.4mm rear bearing? Thought it was only avail from NR at $50. :blink:

Terry;

been running a 21rs in my little girls speedmaster 20 since last season. still on original bearings. runs great.

carl cisneros

Thanks!

Terry

Yes 2003 Model and all long strokes take the same brgs. this is the long stroke, I just received invoice and it cost me about 25.00 + shipping.

Walt Barney

 

[Terry Keeley]

Where did ya get that rear for $25 Walt? Uncle Bill shows $49 on his site... :blink:

 

[Jerry Wyss]

The MAC buggy engine is almost identical to the RS. The RS porting is almost an exact copy of the MAC buggy porting.

I'm selling those engine cheap...you could get two for the price of an RS and I will have parts for a long time to come.

Hmmm, I don't know if you'll see this Andy but does the Mac .21 buggy crank have the same

crankpin arrangement as the O/B crank? Say a pull start or roto-start model?? same possible pto pin h34r:

 

[Scott Schneider]

That rear bearing from BOCA is refered to as bearing# MR25414 TH-9 C-3

Its a 25.4mm O.D. & 14mm I.D. & sells for @ $29.95

** Also bearing #MR2513 TH-9 C-3 thats 25.0mm O.D. & 13mm I.D. sell for $29.95

Front BOCA is # MR607 TH-9 C-3 and $13.95

I'm a BOCA dealer and sell lots of them locally here.

Scott

 

[Terry Keeley]

Thanks for all the input guys, off to Evansville, see ya in a couple of weeks!!!

 

[Joe_Knesek]

Terry I'm sure you are already aware of this but I would not use the Boca bearing in the Nova Rossi Long Stroke. I made this mistake and it failed after 6 heats. I've had the original Nova Rossi bearing in the motors Franco built me for over a year and they are still smoother than the Boca bearing. Granted I do not run that much but I will never run a Boca bearing in this motor.

 

[Chris Wood]

Terry I'm sure you are already aware of this but I would not use the Boca bearing in the Nova Rossi Long Stroke. I made this mistake and it failed after 6 heats. I've had the original Nova Rossi bearing in the motors Franco built me for over a year and they are still smoother than the Boca bearing. Granted I do not run that much but I will never run a Boca bearing in this motor.

yep the boca's are JUNK... don't waste your time.. 2 runs and mine were trash..

chris

 

[J_Moore]

Terry I'm sure you are already aware of this but I would not use the Boca bearing in the Nova Rossi Long Stroke. I made this mistake and it failed after 6 heats. I've had the original Nova Rossi bearing in the motors Franco built me for over a year and they are still smoother than the Boca bearing. Granted I do not run that much but I will never run a Boca bearing in this motor.

yep the boca's are JUNK... don't waste your time.. 2 runs and mine were trash..

chris

Yep i'll third that. I think i ruined 2 nova rossi before i realized that the Boca bearings are garbage in this motor. In every motor the balls split and went throught he motor in a very short time. I know some guys that hardly change there bearings and have got almost 3 seasons on nova bearings

 

[jaxracer]

Terry I'm sure you are already aware of this but I would not use the Boca bearing in the Nova Rossi Long Stroke. I made this mistake and it failed after 6 heats. I've had the original Nova Rossi bearing in the motors Franco built me for over a year and they are still smoother than the Boca bearing. Granted I do not run that much but I will never run a Boca bearing in this motor.

yep the boca's are JUNK... don't waste your time.. 2 runs and mine were trash..

chris

Yep i'll third that. I think i ruined 2 nova rossi before i realized that the Boca bearings are garbage in this motor. In every motor the balls split and went throught he motor in a very short time. I know some guys that hardly change there bearings and have got almost 3 seasons on nova bearings

I guess I'll be the fourth to vouch for Bocas being junk. Had a set in my Nova Rossi and let's just say it wasn't pretty. Half of a ball got wedged between the piston and sleeve and another whole one got stuck underneath the crank. The prices from Boca might be cheaper but so is the quality :angry: .

~Mitch

 

[user 115]

I'm hoping to run a geraghty modifed CMB RS this weekend. I'm running a gerghty frankenstein motor now that has a NR P/S in it so should be able to give a decent comparison.

Charley