Idle Speed Question

I recently purchased a 2006 kx250f, and just had a question about the idle speed for 4 strokes in general. While i have it in 1st gear riding around, if I dont give it any gas, it will just go by itself. Not super fast, but it just goes by itself. We have been trying to get the idle speed right. Should it be doing this or not?

Alot of people that are new to 4strokes have trouble with idle speed and they end up turning it up because they stall, which is probably what the previous owner did. I would play with it and get it to your preference.

Yea, we are adjusting but my main question since we are just moving to 4 strokes is that should it move by itself without giving it gas in first gear.

Preference. I see many people that try to go to low like old style 4t. New bikes have tiny flywheels and some get noisy from the decompresion release if idled low.

Use the idle speed to adjust prefered decel braking. Higher is good if coming off of 2 ts.

Normal idle speed is about 1,800 rpm. To some it seems fast but any slower can induce piston slap. You should certainly not ride about and lug around at idle either. MX bikes are not play bikes and do not tolerate chugging about. They are meant to be raced.

i dont just lug it around in first haha. I just noticed that when i was coming off the track, when i was about to stop i just noticed that it went by itself. I was just curious. I know how to ride a bike, i am just new to 4 strokes, and my 2 stroke never did that.

You 2S had nearly 0 power at idle. A 4S engine carries more momentum in terms of energy in the greater moving parts.

I had to mention about lugging, I have seen some real torturous riders.

Haha yea, thanks for the answer though. Appreciate it, now I know there is nothing wrong.

In my opinion the answer to your question is yes, you should be able to putt around in 1st gear without giving it any gas. It will be very slow but as others said it helps prevent stalling during slow turns/maneuvers. I feel that the factory rec. idle speed is a bit too high so I slow it just a tad, but it's still running fast enough to idle in first without stalling.

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