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Will you driving craze us? ?

That quote shows that you don't know much about the role of nitromethane in our fuel.

Nitro doesn't make the power, methanol does.

Going from 25% to 16% does not slow you down, it changes the mixture you have to run and your temps......

I'm quoting what you wrote right now.

Someone who is more expert than you will explain power and nitro percentage in rc fuel.

Problem with Flash .21 PTS
 

Hi there,

I would like to ask same help. I bought a Novarossi engine Flash .21 PTS Revisionato from the store in Italy last year but only made the braking in a month ago and tried to run with it but couldn't because i didn't find the correct tune and was afraid to brake the engine. The problem is that on a straight when i go full throttle the engine goes down as it was broke, and that scares a lot. I put my hand on the flywheel and it's ok, start the engine again and it's normal, put the car again on the track give same laps to heat the engine and try again and makes the same thing again, i tried to open just a little the maximum needle and the engine stays to rich and doesn't run good. Could you please help me to see what i should do? I´m ussing MLC fuel 16%, the engine has .60 shimming and use a glow plug 7 TGF

What are your opinion?

Thanks,

hi we have had 12 from there and most of them are modded /cranks/ex race motors with new piston rod and what ever rossi find is worn when they get it back if it is ex/race it should have a red dot on one screw they run in really quick as goes like hell hope yours goes better when you find out what's going on ours runs lean on bottom/took a hole nats to get it to Idel properly 21 shoud be on 25% NITRO or you shoud change shims////I know little about 21 as we race 12 most of the time I have had my foot in my mouth before when I am not shore but some one on hear will sort you out

25 % Nitro vs 16% Nitro
You don’t get as much RPM’s with 25% nitro as you would with 16%.
With 25% you naturally have to richen the engine, it gives you more low end power due to the 25%...but just not all the power at top speed.
With 16% nitro you can lean it out for more top end power.

NITROMETHANE. Also commonly referred to as NITRO for short, is derived from propane. In itself, nitro is not even extremely flammable as one might think. The real power producing potential of nitromethane is that it carries additional oxygen with it into the combustion process. It acts as a fuel too, but the molecule carries oxygen along with it. In a way, nitromethane is sort of like a chemical "supercharger" for an engine. It helps get more oxygen into the engine to help burn more fuel and produce more power, but because the flame speed of Nitro is much slower than that of Methanol, adding Nitro to the mixture slows the flame speed. This should not be a problem until you hit very high rpm’s. There's a moment where the engine cannot pickup more rpm’s because it needs to burn the mixture at much higher speed in the combustion chamber. 25% also burns at a lower temp so it will give you advanced timing and therefore more low end power.

With lesser nitro, you may need to lean it a little more and your fuel mileage will be a little better, temps will vary but combustion chamber and carb setup need to be revised, but... more nitro doesn't necessarily mean more power, but yes more fuel consumption and less runtime for the same CC’s.

Higher nitro content does not cool the engine, in fact it creates more heat. Basically, more nitro = more oxidizer to the methanol which in turn creates higher combustion pressures which create more heat.

AFM

there second hand race motors come reseal and security seal on the box.

go for a 7TGH glow plug, the 7TGF, is to cold I think for 16%
Maybe even go to a 6TGF....

Still waiting!;)

I have a brand new Nova Rossi Bonito .21 engine for my GT. I am like 4 years away from racing NITRO and I am sure I am way off about tunning or setting for nitro, but I want to know...if I am running Byron 25% thru out, do I have to remove ADD any head shim just to not blowing glow plugs on every round..?

I know back then...when running 30% fuel, head shim need to be added in order to not giving too much compression when running 30%. But for the Bonito, will the stock head shim thinkness is OK for 25%? From their diagram, it listed there are two 0.3mm and one 0.2mm that is = total 0.8mm. I have no problem to add 0.1mm more on the head as I DO NOT need the motor to run the absolutely fastest. I want my glow plug to last and not having the engine shut off on a one hour race...

I will just follow the manual said and run in the engine for 30 minutes and then lean the crap out of it...LOL

is the kappo same as kangaroo? except for a 25.8 bearing

Stock shims will work with Byrons 25%. For GT use, we do recommend using the C8TGH glowplug (on-road) instead of the off-road plug that comes with it.

Same engine, both use the 25.8 rear bearing.

thanks! so, the Piston Set can use on the previous R21 or Kangaroo, can't it?

Maby someone can point me in the right direction to look for a reason for the strange behaviour of my sons Novarossi Flash .12 with 2660 pipe.

Towards the end of a nice training session (about 12 tanks of faultless operation) the engine started suddenly to go extremely rich 1-2 times per lap for a short period like 2-3 secs and then operating well again. No changes were made in any settings. Temps were normal about 125-128 celsius before disaster started and then temps dropped very much. For some reason the engine flooded on its own for short periods and then continued normal operation on its own. When the problem was on it sounded like a new engine during early breaking in and it would not take any higher rpm.

What could cause a normally functioning engine to start suddenly going extremely rich for short periods of time and return to normal? And this repeated very poor / running well / very poor...

Before the session we put in a new air filter and afterwards it looked like the carburator had somehow flooded up to air filter too.

Any similar experiences?

Air was about 20 celsius and weather was sunny and dry.