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Bear with me for a long post:
I rejected my 02 200 the other day, 158 main, 42 pilot, stock needle 3rd clip from top. No airbox lid. Anyway, I took a short ride around the yard and it ran like a top. Today, took a ride and its back to bogging until half throttle. I take apart the carb, reassble, and it runs awesome-for a few minutes. Then it's bogging again-and usually it will try to backfire before I get a complete kick on the lever. I can smell strong gasoline even when the petcock is off. There's a noticeable white smoke that accompanies this behavior. My plug is like new save for a coating of wet gasoline. I set my floats to 19mm but my method may not have been precise enough. As I type this I can smell strong gas odor while my bike is not running and petcock is off. Any clues?

The floats should be set at 16 +/- 1 if you are using a Keihin 35mm.

Oddly enough, I just installed an inline fuel on/off valve from a hardware store, and the problem seems to be solved. Strange. It acts like its just swimming in gas, so I'd say floats need reset as well. For the time being though I'm back in business. On a side note: I noticed that my clutch side crank seal had 3 small indentations in the case aluminum, and one of them looked like it was thin enough to see a small portion of the seal? I jb welded it closed, but has anyone else seen something similar?

Sounds like your float level is too high, it should be 16 +/-2 mm. The correct way to measure it is in the manual, but suffice to say if you had the carb upside down (so the float bowl would be on the top) then you did it wrong and your floats are probably further off than you think. You may also want to check the float and its corresponding seat and make sure it isn't damaged as well as your petcock assembly to make sure it is operating correctly. If a new inline valve helps, its likely because the petcock is leaking (when in Off) and/or the seat is'nt fully engaging. If you let these bikes sit long enough on the side stand with the gas on, they all will leak some.

Actionman wrote: On a side note: I noticed that my clutch side crank seal had 3 small indentations in the case aluminum, and one of them looked like it was thin enough to see a small portion of the seal? I jb welded it closed, but has anyone else seen something similar?

??? I think you will need to post a picture of that one.

Sadly, I didn't get a pic. Imagine looking inside the clutch-side case around the power valve bearing and water pump bearing; above those bearings is the crank seal(actually the seal is facing the crank, but you get the drift. The part of the case that holds the crank seal has 3 oval shaped indentations, and one of mine absolutely looked like I could see a sliver if the seal through it- like the metal was thin there. Could've been bad lighting, but I put some jb weld in those indentations.

bufftester wrote:Sounds like your float level is too high, it should be 16 +/-2 mm. The correct way to measure it is in the manual, but suffice to say if you had the carb upside down (so the float bowl would be on the top) then you did it wrong and your floats are probably further off than you think. You may also want to check the float and its corresponding seat and make sure it isn't damaged as well as your petcock assembly to make sure it is operating correctly. If a new inline valve helps, its likely because the petcock is leaking (when in Off) and/or the seat is'nt fully engaging. If you let these bikes sit long enough on the side stand with the gas on, they all will leak some.

I have heard multiple people say you shouldn't measure it sitting upside down but my manual specifically states you should.


Notice the note at the bottom.
Some people have said the float shouldn't compress the little pin, etc, etc. I just followed the manual and have had no issues.
I guess you could hook a hose up to the drain like in the first part to confirm. I've never tried it though.

Interesting difference between the 2 manuals. The one I have says "When checking the float height turn the carburetor sideways with the float hanging from the pivot pin. Angle the carburetor back about 25° so the float is resting on the fuel valve but not compressing the spring inside of it. Measure the distance between the float bowl gasket surface and the highest part of the float with a set of vernier calipers or float height gauge" which is the same procedure in all my other bikes service manuals, both 2 and 4 stroke. Of course, the spring in the valve has about 1 mm or less of travel, so you would still be in the same tolerance range either way. Doing it upside down is certainly easier to hold the carb and the calipers.

bufftester wrote:Interesting difference between the 2 manuals. The one I have says "When checking the float height turn the carburetor sideways with the float hanging from the pivot pin. Angle the carburetor back about 25° so the float is resting on the fuel valve but not compressing the spring inside of it. Measure the distance between the float bowl gasket surface and the highest part of the float with a set of vernier calipers or float height gauge" which is the same procedure in all my other bikes service manuals, both 2 and 4 stroke. Of course, the spring in the valve has about 1 mm or less of travel, so you would still be in the same tolerance range either way. Doing it upside down is certainly easier to hold the carb and the calipers.

Mine is the official shop service manual for 1989. Maybe down the road they realized it was better to do it the other way.

I'm using cyclepedia, maybe someone who has the 95-06 200/220 print manual can look it up and see what it says for comparison.

I have the "Second Edition Dec. 10, 1996" H series book and it shows the gauge with the hose and it shows the carb being tipped and says that "the tang on the float just touches the needle rod in the float valve." and there is a note that "The needle rod must not come out during the float height adjustment."

Spec is 16 +/- 2 so probably it really doesn't matter that much because the height would still be in the range compressed or not. But if you are taking the time to do it you probably might as well do it right.

My brother has a ktm with a pwk and there manual says set the float by holding the carb at 45 degrees. And adjust until the float touches the needle at that angle.

Yep, I've got to reset those floats. It ran like moldy ass today, so I'm going to fix it tomorrow. Boo!

I reset floats til I'm blue in the face, and still no respite from carb woes. I have, however, decided that its more of a "stutter" from closed throttle to 3/4 fully open throttle instead of a bog. Could I be too lean somewhere instead of too rich? 42 pilot, 158 main, stock needle with clip in top position. No airbox lid. Cdi problem? Anyone else ever chased a problem like this?

The pilot and main seem to be in the average range but it might be worth dropping the clip back to the middle and see if that helps.

Ignition problems can be tricky to get figured out if it isn't a constant problem.

compression check?

air leak between the carb/engine? or air leak into carb? clogged passage in carb(maybe soak it in cleaner)?

New gasket on reed valve, tightened to spec. Airbox boot sealed and crack-free. Carb has been dipped, soaked, massaged, and talked dirty to. Carb passages cleaned with guitar strings very gently. Reeds are perfect. One odd thing I've noticed is that the filter-facing part of the slide is coated with a slick white substance like lithium grease everytime I disassemble the carb. I assume its the filter oil, but I'm wondering what it is now? Not burning any oil, water, nor is any fluids mixing together in the radiators or tranny. I assumed a 42 pilot would do it, but could it need another drop in size? I'm a +700ft altitude in eastern ky. Need a new needle maybe? I'm at 125psi during my compression check. Seems like the good end of the scale I'd think? Forgot to add that my plugs like great, save for a shiny coating of gas.

Actionman wrote: Carb has been dipped

If you dipped the carb then you most likely need a new jet block o ring. The o ring doesn't fare well when the carb is dipped in carb cleaner. You need to check that before you go further.

Actionman wrote: I'm at 125psi during my compression check. Seems like the good end of the scale I'd think? Forgot to add that my plugs like great, save for a shiny coating of gas.

I know the book says that you can go down to 98 or so (H series) but I would really start to think about a new top end at 125.

Dipped was just a figure of speech. I soaked my carb in dawn dish washing liquid and then cleaned it out with warm water, sprayed out the passages, cleaned them out with wire, then sprayed them again. My psi was 135 not 125, sorry. It's hard to type on my phone when the ends of my fingers look like miniature German soldier helmets.

Actionman wrote: One odd thing I've noticed is that the filter-facing part of the slide is coated with a slick white substance like lithium grease everytime I disassemble the carb. I assume its the filter oil, but I'm wondering what it is now?

What are you using on your filter? You have had problems with water in your filter box, did you clean your filter since then?

*I hate carbs. Every time I try to fix them I make it worse, so don't pay any attention to me.