Choke - 250R Ninja 2010

[Br3ndan]

Hi All,

I just bought my bike a few days back and would like a run down on the use of the choke?

I know the concept of it,,, and what it does but I am wondering the following things.

1) Do i need to use the choke everytime? Or do i try to start the bike first without it?

2) How long do i leave it on for? If i start the bike, put my gear on and ride off is that long enough to flick the choke off?

3) Whats the normal idle for this bike? I am assuming around 1000 -1500?

Cheers guys!

[nd4boost]

Hey man, choke should be on full before starting cold. I turn my choke all the way on, twist the throttle twice and then start it. Choke should be left on for the 2-3 minute warm up or until bike is ready to ride. I gradually turn mine down until it can idle on it's own

[IvanM]

^^ WHS

Also want to add that you have to turn off your choke when you're ready to ride (if you can't wait for it to warm up ).

With the choke fully open I start up my GPX and it idles at 5k. I immediately reduce the choke until it's around 3k and leave the engine to warm up for a minute. I then close the choke and twist the throttle once or twice. The bike should idle at 1.5k after that (even though it's still not fully warm).

[Br3ndan]

Thanks for the advice guys ! Much appreciated !

[Barfridge]

Now that the weather is cooling down, you may need the choke. With my GPX I never used it when the temperature was above about 20 degrees, it just wasn't required.

[g0zer]

choke with closed throttle for cold starting for all carb systems with manual chokes.

soon as the motor starts to stumble on the extra fuel close the choke. in australia its not so cold, i only use choke to get a bike to fire and after a few seconds close the choke, give the bike a couple of blips and the idle will settle down so the motor can finish warming up by itself.

choke circuit is designed to work with closed throttle, its the intake vacuum generated behind the closed carb slide that draws extra fuel through the choke.

Carburetor - Wikipedia, the free encyclopedia

When the engine is cold, fuel vaporizes less readily and tends to condense on the walls of the intake manifold, starving the cylinders of fuel and making the engine difficult to start; thus, a richer mixture (more fuel to air) is required to start and run the engine until it warms up. A richer mixture is also easier to ignite.

To provide the extra fuel, a choke is typically used; this is a device that restricts the flow of air at the entrance to the carburetor, before the venturi. With this restriction in place, extra vacuum is developed in the carburetor barrel, which pulls extra fuel through the main metering system to supplement the fuel being pulled from the idle and off-idle circuits. This provides the rich mixture required to sustain operation at low engine temperatures.

Some carburetors do not have a choke but instead use a mixture enrichment circuit, or enrichener. Typically used on small engines, notably motorcycles, enricheners work by opening a secondary fuel circuit below the throttle valves. This circuit works exactly like the idle circuit, and when engaged it simply supplies extra fuel when the throttle is closed.

[Red_is_Best]

IIRC There is a section on this in the manual, with recommendations of rev range. Once I got to know the bike you could distinctly hear the change in the engine as it warmed up and no longer needed it.