Need help with a Nova Rossi .21 Carb

[Carl Ervin]

Ive raced all kinds of nitro stuff and am no stranger to barrel and/or slide carbs but this one baffels me. Why does this thing have 2 control horns and what looks 2 high speed needles. And what are the flat tipped screws in the inside of the adjustment needles for? Can anyone tell me what tunes and adjustes what? And what are good settings for the break-in ? Thanks!!

 

[Ron Olson]

Carl, what you have there is a third channel fuel mixture control that is built-in to the high-speed needle as opposed to those that are remotely mounted.

The screw inside is the low-speed needle. They keep it hidden so that people don't mess with them!

 

[steve wood]

Ive raced all kinds of nitro stuff and am no stranger to barrel and/or slide carbs but this one baffels me. Why does this thing have 2 control horns and what looks 2 high speed needles. And what are the flat tipped screws in the inside of the adjustment needles for? Can anyone tell me what tunes and adjustes what? And what are good settings for the break-in ? Thanks!!

it has a low speed needle, a high speed needle and an arm for 3rd channel mix. we remove all the garbage, cut off the threaded portion and solder up the hole, then make an adapter that screws into the barrel that will take a standard mac or cmb arm. also have to cut back the spray bar to get rid of the notch. this way you can press out the spray bar assembly and rotate it to have the inlet point where you want it to, then press it back in. you have to use a remot needle or third chanell mixture control when this is done. now i know why i hate typing!!!!!!!!!!

 

[Tofastformellow]

i prefer to use a cmb ls 21 carb.. works real good.

but the mixture thingy i use is a grim valve mounted to the tub..

Jason

 

[Mike Larson]

Hey Carl! The carb is not that hard to set up. You will have to set up a third channel system in your boat, ie: 3 channel receiver and the servo to run the carb..... Once you achieve this... you will never ruturn to manual needle settings.... Gain access to a boater with a flowmeter to set the range of the 3rd channel from 2.8 to 4.2 or so. Break in the motor gently starting with the carb set at 4.... if its too rich to run use the third channel and lean it a little at a time until you can achieve a few tanks of rich running.... NEVER lean down until you think the motor is through break in.... Once youve accomplished breaking it in... use the 3rd channel to tune for the days conditions..... always starting rich and "clicking" down till the boat turns on.... Kinda novice hints.... thats how I did it.... the dead boat scenarios are a thing of the past..... good luck.... mike