I'm posting again some helpful Tips on Sirios

For your records, below is the official answer I got from the factory concerning conrod life for the Sirio S12. Also I did measurement to crank pin on a new stock engine and found that it has 4.428mm.

"The right play between crank pin and conrod bushing is 0,04 - 0,05 mm. I don't know if you're able to check it, but I suggest you change the conrod every 2-3 hours running.
The life of the conrod depends mainly on the fuel you use, as the lubrification and the right carburetion keeps your engine running well for long time."

Regards,

ANDREA ROSSI
Lavorazioni Meccaniche srl
Via Meucci, 3 Seggiano di Pioltello Mi Italy
Tel +39 0292160235 Fax +39 0292160581
Visit our Web Site at :
WWW.STAR-MOTOR.COM

From calculations about conrod life, according to Sirio factory, one should change the conrod between 0.4756 to 0.7133 gallon.

How come??? Well, if a 75cc tank lasts an average of 5 minutes, one makes 12 tanks in 1 hour, which is 900cc. So according to Sirio that says change conrod after 2 to 3 hours running, that means change conrod between 1800cc and 2700cc of fuel. Now if 1 gallon has 3,785cc, that means the lifetime of the conrod is less than one gallon.

BREAK-IN

After reading a post by Andrea Rossi in the Sirio's web site, this is the correct Break-In procedure for the S12's

1.- One (1) tank in the bench at WOT with very rich setting of HSN, avoiding it to go on 4 stroke.
COOL DOWN
2.- Three (3) tanks on the track with very rich setting of HSN, and tuning the HSN at the end of third tank to get almost full power.
COOL DOWN AFTER EACH TANK
He says after that, the engine will give more power after every new tank.
3.- For 20% Nitro, use .20 head shim and N° 7 Glow plug.

Which means that Break-In should be done with more or less 300 to 500cc of fuel.

AFM

Exactly; bushing wore too fast. Luckily I was able to get 2 new rods. I am hoping they have good bushing strength b/c I think they are from the original s12s which had no issues that I know of.

WOW!!!! Less than a gallon of fuel, that's pretty lousy!!! I like power these Sirio 12's have, but I dont think it's worth the xtra $$$ you have to put out every month or so for a new rod, depending how often you race. I have a Novarossi RX 21 Kangaroo engine I ran in my Slide all last year. I have over 8 gallons of fuel through it and it still has excellent compression and it still gets stuck every so often when trying to start it. I guess you can't beat the quality of a Novarossi.

The Sirio conrod seem to work fine on my EVO2 so far have been running at least 1 gallon of fuel thru it and the engine is still going strong, in fact I feel it getting stronger and the pinch on at TDC is still there. Btw I am running O'donell 25% on my FW05R on a mid size track and I have no problem catching those guys running JP

u r puttin the jp's to shame....

Can someone give me some info on a Sirio motor I saw at my LHS.Its says on the bow "Sirio .12 SG shaft 3 Port ECO.".What are the specs on this motor?

Check the connecting rod clearance with the crank pin. Give us some numbers please!

I think it's a quality issue; I.E. Sirio has some rods with soft bushing material out there.

I did measurement to crank pin on a new stock engine and found that it has 4.428mm.

The right play between crank pin and conrod bushing is 0,04 - 0,05 mm.

AFM

I have question regarding the EVO2. Are the 3 port version all standard plug or do they come in a "ROAR legal" turbo plug version? Thanks.

Thank you "afm", for your ticks. This weekend i race in the 3Š probe spanish national, and my Sirio are a misil, i go very fast.
I see, same power and speed what others motors , JP , RB ...
i donīt put in the final, becouse my driving skills arenīt good, i only have this car for 2 months, and i not confident with it.
Only 3 seconds....
but i are very happy, with my car and my motor.

Only, one mistake,...i broke de crank shaft. I think, the fault are of the batteries of my powerstart, they are a LRP GP3300 (120€ c.u) , the max. selection from my electric touring car.
the piston are in the TDS, and i not see, i probe the start my motor, but i speek "crack"...

I use in the 710 , 16-59 / 22-56 , in a medium track (230 meter) the straight are 60 meters, more acceleration and ultra fast.

Did you use a micrometer or caliper?

Congratulations luis, what pipe did you finally use???

Rigt now I'm in Madrid, and will go shopping for parts for my Sirio, and will be present at Alcobendas next weekend for the 1/8 th Nationals. I'm at 91-650-8842 (Alfonso), if you wish to talk.
AFM

I went to a lathing shop and measurements were done with digital micrometers.

AFM

So I take it your conrod clearance is remaining constant?