05 Honda crf250r has miss in throttle . When I give it gas quick I will choke o

What's wrong

The infamous Honda bog. Need to mess with jetting, may have to do AP mod. I was able to cure it with just messing with the fuel/air mixture.Good Luck

Here's a quick explanation.

Lets say your bike is running properly at idle, meaning it is not too rich or too lean.

If you then open the throttle quickly, a rush of air enters the engine and will lean out the engine until it shuts off from fuel starvation.

In order to prevent this, modern carbs have an accelerator pump, which shoots extra fuel into the intake when you twist the throttle, like a squirt gun.

This pump can be adjusted to squirt more or less fuel.

To tune this, you need to first get your pilot jet/main jet/needle/float all set up properly, then adjust the pump to squirt enough fuel so that you don't encounter this lean spot.

You can do this by changing the jet for the pump.

A lot of people do an o ring or safety wire mod to the pump which bypasses the pumps normal setting and makes it just shoot a lot of fuel.

It isn't technically the "right way" to tune the accelerator pump, as it makes the bike briefly run a bit too rich when you hit the throttle, but in reality it works pretty well to fix the lean spot.

purchase a factory R&D AP bowl with ALJ

Then dial in the leak jet

Well that explained it all . It runs perfect at idle but soon as you twist the throttle it chokes and dies .

So should I just adjust the jet and see where it takes me ?

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