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Nitro Engine needle settings


How to setup brushless motor.

Part 1 <Part 2 <Part 3 <Part 4 < Part 5


How To Tune the Engine?

1. What other tools and accessories do I need so that the nitro powered Vehicle will run? ans.
2. Prior to running what must I do? ans.
3. My car will not start when I pull the starter cord. ans.
4. My car starts but I cannot keep it running. ans.
5. My pull cord is stuck and will not pull. ans.
6. Nitro engine break in procedure. ans.

1. What other tools and accessories do I need to enable my nitro powered vehicle to run?

You will need 12xAA batteries. 8xAA for the radio control transmitter and 4xAA for the car servos. You will also need Nitro Fuel, we recommend 10-20% Nitro and this can be purchased from most local hobby shops. Lastly you will need a Glow Plug Igniter since it is a necessity, which normally retails for $29.99! This can be purchased at time of checkout or at any hobby store.

2. Prior to running the vehicle, are there any preperations that I must do?

There are a few things everyone must do prior to starting the first time.

1. Air Filter Oil should be used on your air filter. This will prevent dust and dirt from reaching and damaging your engine. Air filter oil can be purchased from any hobby shop.

2. Fresh batteries; this is important, due to problems and symptoms that can be caused by weak batteries.

3. Fully charge Glow Plug Igniter.

4. Prime the fuel line. See below.

5. Find an open area.

3. My car will not start when I pull the starter cord, how can i fix this?

The first thing that many new users of Nitro Cars need to know is that a Glow Plug Igniter is needed. The Glow Plug Igniter must be fully charged prior to attaching it to the glow plug. If it is fully charged and it is attached to the Glow Plug, make sure a good connection is made.

Second, if the above is done you should check to make sure that fuel is getting to the carburetor. This can easily be done by holding your finger over the exhaust hole and giving a few pulls on the pull start. This will cause fuel to siphon through the fuel line to the Carburetor. Make sure that you do not pull the pull cord all the way to the end. Using the pull start is a learned art and can easily be done with short quick pulls about 1/2 of the way.

Third, if the above two do not resolve the starting issue, you may have flooded the engine. You can remove the glow plug and turn the car upside down and pull the cord a few times to clear out the fuel than restart.

Lastly, your settings may be misadjusted. If you continue to have issues, we highly recommend that you visit a local hobby shop for guidance on the correct starting procedure and setup.

4. My car starts but I cannot keep it running.

This is common for all new cars. All cars need proper throttle, rich & lean adjustments to get the car running just right. We recommend visiting www.rcuniverse.com for further information on how to tweak your car so that runs perfectly. You can also visit a local hobby shop or visit local races in your area so that you can learn the tricks and tweaks needed to enjoy your RC Car to its fullest.

Some symptoms of misadjusted engines and carburetors are:

1. Car does not start.

2. Car starts but will not stay running.

3. Car starts but exhaust spits out amounts of gasoline.

4. Car starts but each time I use the brake it stalls.

5. Car does not seem to have power.

5. My pull cord is stuck and will not pull.

You should remove the glow plug to release the pressure within the engine and pull the cord a few times to free up the cylinder. Reinstall the glow plug and try again. This usually resolves a stuck pull cord. If it doesn't, your cord may have come off track and you can simply open the rear of the engine and check to see if adjustments need to be made.


Break in procedure for higher displacement and standard engines.


Before you even attempt to put fuel in your engine. Set the engine on a bench, or in your r/c car. Remove the glow plug and place after run oil down the centre of the head of the engine where the glow plug is placed.


Dry run the engine with a starter box or some other means of turning the crankshaft for about 20 mins taking (5 minute intervals at a time) to make sure the piston wears into the sleeve. Even though you might have a pullstart engine or electric starter you will not have a problem with using a starter box for this purpose.

Also note that using your electric starter unit for more than 20 seconds at a time could burn out your electric starter motor. We do not recommend using this device for the above mentioned process in step 2. Electric starter can be replaced with a cordless electric drill for this process. Then you can use your electric starter unit for starting purposes as in normal use, after the above process have been met.


Set the engine in the vehicle or run it on a bench or whichever is suitable for you and run the engine on idle for 2 full tanks. Please note no more than 15% nitro mixture of fuel for the break-in of the engine is recommended. Using an electrical fan for cooling is also recommended.


Don't let the engine rev up and make sure it stays cool around 45-60 degrees Celsius, use an electrical fan if possible to cool the engine head assembly.


For the next 6 to 8 tanks, the engine should be kept under half throttle running the engine rich. Remembering that most engines come already factory set at the fuel rich position on the needle (top end needle) (Turning anti clockwise you richen the engine, turning clockwise you lean the engine on your fuel top end needle).The bottom needle setting must not to be changed it, it is factory set. (Only experts may use this setting.)


You should now be able to start tuning your engine to your preference.

Please note that if you run your engine too lean you will damage it, no matter wheather it is a high performance engine or standard engine.

Himotoracing infomation:

From what we have experienced with high performance and standard engines including Nova Rossi, Sirio, and RB, force, Team Infinity or Vertex engines that they have a very long and extensive break in process that if followed it will give you a problem free engine for a very long time.

Don't arrive at the conclusion that breaking in your engine, no matter what type of brand of engine it is, that if you run 4 tanks of fuel through the engine that its enough breaking in, because this won't do at all and your engine will have a very short life span.

Please note that anyone who is a novice and has never owned a nitro engine, please ask your local hobby shop expert for help on the breaking in process of your engine.

Do not attempt it yourself if you are a novice.

Have fun racing/bash around the backyard or the tracks and may your engine last you a very long time.


If at anytime your pull-start or electric starter becomes hard to start the engine, stop and don't attempt starting the engine until the problem is solved.

The problem is maybe that your engine is flooded with excessive amounts of fuel.

Loosen the glow plug with your glow plug tool until your engine seems to have less compression.

Pull the pull-start or rotate the electric starter a few times to clear the excessive fuel in the combustion chamber.

Once you have completed clearing the excessive fuel from your engine, tighten the glow plug up again then release it 1/4 of a turn. This will give you a little less compression for ease of starting.

Place the glow igniter on the glow plug.

Start the engine by pulling on the pull-start or using the electric starter.

Once the engine is fully started and is idling, tighten the glow plug while engine is still in running.

This procedure above will save you from breaking your pull-start cord and damaging your one way bearing and engine.

Please note new engines have high compression and may be difficult to start if you don't follow the instructions above.


Which percentage of nitro should you run?

Everyone you seem to ask has a different opinion of what type of fuel to use. No fuel is ideal for every application or is it a fact that a higher percentage of nitro results in better all round performance. The correct percentage of nitro in a fuel and its effects on engine performance are rather complex issues due to the many variables as in climate, humidity and glow plugs used. To understand how nitro content affects engine performance, it helps to have a little basic understanding of nitro.

Nitromethane is a monopropellant which means it can burn in the absence of air.

Nitromethane contains nitrogen and oxygen, which provides more "fuel" for the combustion process.

The oxygen contained in nitromethane is released during the combustion process allowing richer needle settings that pack more fuel in the combustion chamber.

More fuel plus more air potentially equals more horsepower when engines are designed to run on fuels containing nitromethane or the amount of nitromethane that you run.

There are a great deal more technical aspects to Nitromethane, but this explains why you can produce more power with it.

Now running more nitro does not always mean more horsepower, the engine has to be designed to run the amount of nitromethane you intend to use. Running 30% nitro fuel in an engine designed for low to no nitromethane content, will not yield anything but poor, hot running engine characteristics. Using 0% nitro fuel in an engine designed for 20% or higher nitro will yield equally poor running engine characteristics.

RC cars and trucks with engine sizes .12-->.18 usually use 10%-20% nitro content fuel with 8%-16% oil content. It is hard for one person to tell you which fuel to use for your particular vehicle due the varying conditions of your surrounding area. If you wish to find out what really works, go down to your local track to see what everyone uses, that's the easiest way. RC cars and trucks with engines from .21-->.27 typically use more nitro content. The common range is from 20%-40% and around 8%-18% oil content. Fuels have different oils, and at different altitudes their flash points are different, so some people say a particular fuel is good, but for someone else it is not. It is mostly trial and error for which fuel will run best for your liking.

***Please note not following the above procedures will void the warranty on your engine


Himotoracing...Technical Support