Ok i just got a 2004 crf 70. i have taken carb apart twice and cleaned every jet ect... problem is when wide open it cuts out spits and spudders. I have changed settings on throttle cable and swapped out another carb and is doing same thing. I crack open the choke just a little and it runs great. what can be going on?

It sounds like you may have some dirt or debris in your main jet inside your carb. You will have to remove the carb and then remove both carb jets>>pilot jet<< and >>main jet<< . Check them for blockage by holding up to the light and see if you can see thru them. The holes in the jets need to be fully clear and appear perfectly round. You can use a wire brush bristle to clear both jets.

Hello, it sounds like a fuel delivery problem. Start with the fuel petcock, make sure it is clean and gas is flowing freely to the carb. Check for vacuum leaks.
If that is ok, the idle/pilot jets & circuits are probably clogged & will need to be cleaned. I hope this helps.

The carburetor needs to be taken off then the float bowl at the bottom of the carb. Trash and water and varnish have plugged up the jets in the carb and is causing the float to stick open. Get a can of spray carb cleaner from the auto parts store then spray into every hole in the carb. Remove the choke and the throttle and air screws and spray into those holes as well. What goes into one hole should come out of another. Wear goggles to avoid getting any spray in your eyes.

clean fuel and air filters,if no help you may need to remove trash from carb.(jet, float valve and seat)

Chances are the air filter is extremely wet. Air can't get through a wet filter, and if no air can flow through the carb, no gas can flow through either. Remove the filter and try again to get the engine started. I assume you drained and cleaned the gas tank already. If still no joy, remove the carb and clean it using spray carb cleaner. Remove the air screw and throttle screw and spray into the screw holes as well as all the little drill holes in the carb body. The object here is to clean out the pilot jet and idle circuit. When re-assembling the carb, put the air and throttle screws back in and turn them inward until they LIGHTLY seat. Now open each of them up one and one half turns. This is the factory setting. Please rate my answer.

check ya carb jets or take the carb(s) out and clean it with carb cleaner. also just give some air pressure to the jets. Or cud be you air filter too.

Sounds quite typical of a small four cycle engine; twisting the throttle open rapidly just leaves them gasping for air. The best you can do is make sure that the basic state of tune is correct (clean air filter, valves adjusted, timing set correctly, etc.). The changes you've made to the jetting and the throttle needle sounds like you're going in the right direction - and may help. But don't expect too much.

Carb jets need cleaning.

The key to your problem is the phrase "Also the carbs were just cleaned"
You have done something wrong.
Check for air leaks, worn seals, worn needles, etc. cleaning the carbs is the obvious point at which something was last changed.

The carb jets need to be cleaned.


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