Way too much backfiring!

[super90]

So lately my 200x has been backfiring way too much, even when you let off the throttle going 5mph it starts popping horribly. It used to just pop once or twice sometimes but now it just got to the point where its annoying. What are some things i can do to shut it up? So far ive messed with the air/fuel mixture screw on the side of the carb, and the small screw on the bottom of the float bowl (not actually sure what it does but im guessing it is sometime for the fuel flow! I was also thinking about raising the needle clip a couple notches since it dosent idle. The only time it will idle is when i put the air/fuel mix screw all the way in, but then it usually revs up and stays revved for a minute, and im guessing thats running too lean.

So what do you guys think I could do to stop the backfiring and make it idle correct?

[bigreddaddy]

Well it could be running too rich, or it could be a timing issue. I don't currently have a 200X but sounds like the screw at the bottom of the carb is for draining it.
Have you checked your air filter? Where is your main needle set at now? Are you running the stock main jet? Stock exhaust?
Oh yeah, what does your plug look like?

[super90]

I forgot to check that out, Its never fouled out yet and the engines never been opened except by me when I replaced the clutch plates. If it was the timing wouldnt it skip when I kicked it over? And no its not the drain screw, Theres another one with thats is vertical and you need to remove the whole carb to adjust it. So if it is running rich, should I: raise the clip, bring the air/fuel screw out a few turns to compensate for the more air flow? Im completely confused by carbs also BTW.. They just never work out for me

[bigreddaddy]

Yeah carbs can really be a pain. Well, do you have two adjusting screws on the side of the carb that are easy to get to? If so then I don't know what that other screw by the bowl is.
If you only have one adjusting screw on the side then the screw by the bowl is probably the Pilot screw.
There are two adjusting screws on a carb, air and pilot.

The needle clip needs to be raised which causes the needle to stay in the main jet longer allowing less fuel to flow.
BUT, the needle position does not affect the idle. That would be your Pilot jet, Pilot screw adjustment.

Have you taken the jets out and cleaned them? If the pilot jet is plugged it will give you problems starting and idling.

If your Pilot adjusting screw is the one thats vertical then you definitely need to adjust it. Start at 1 1/2-2 turns out (turn left). The pilot screw needs to be adjusted first then you adjust the air screw (start around 2-3 turns out).

I know its confusing at first but after messing with it for a while it gets easier.

So start by finding/adjusting the pilot screw as long as the carb has been cleaned recently. If not then go through the carb real good first and make sure those jets are clean.
Also make sure you have a clean air filter.

[Vealmonkey]

Super90, Check the rubber boot between the carb and the head for cracks. Also make sure the carb is securely bolted to the intake and the intake is securely bolted to the head. If the intake sucks air, it makes it pop sometimes. Also check the exhaust gasket, I've seen where the exhaust had a leak at the junction where the exhaust gasket was and that helped to make a bike back fire too.

[dblshockpower]

Ahmmmm....

Adjust your valves.

[Dangerous-UK]

As mentioned above,the exhaust gasket leaking causes back firing

[riverrat]

It won't idle?

Clean the carb out first, then try all that other stuff.
Make sure your float is ok.

[super90]

Alright, so it wasnt the valves or timing or exhaust leaks. Heres what I did, I raised the needle clip as far as it would go, gave the air screw 2 1/2 turns out and gave the pilot? screw about 2 turns also. I went for a quick ride and noticed that on the bottom end it bogged some and that when you let off the throttle it wanted to keep going, which eventually brought me into a small group of saplings after I went down a hill. So when I got home I turned the pilot screw in about 1/2 turn and everything is fine. Idles perfectly now and everything. Thanks for all the help!