Help. Diagnosing problem carb? Plug?

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If you look at this chart you'll see that your plug looks Oil Fouled:
http://www.4secondsflat.com/plug_chart.html

The smoke at startup could be Oil burning off.

What does your Oil level look like when the Bike is Level ???
If it's above the Top line on the Oil Sight Glass then you need to drain a little out ( I keep mine at 1/2-2/3 between the 2 lines).
If it's at the correct level you probably need to adjust your valves and check/replace the Valve Seals.
 
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Thank you Steve,

The plug does have a dry sooty look, but if I use my finger to rub it, it certainly leaves skid marks on my finger. It doesn't seem to have an oily appearance, but I didn't use it for a long time, just a 10-20 minutes ride.. Maybe not enough time to make it really look oily?

If I take the plug out after running the bike, the plug does look black and a little wet and I can smell gas. But if I leave it out after a while, it looks dry (evaporates?).

If you can smell fuel it probably is which would suggest an over fuelling issue.
I should have said an oily skid mark - soot will do likewise but will be dryer.

The smoke on the RH side is probably some excess fuel that has leaked into the cylinder and is being burnt off.

Can you smell fuel in the oil?
 
Thank you,

I have another picture, taken as soon as I pull the plug out. So this one looks a bit wet. But I know I really need to learn to take a better picture. Not sure you can see the detail.

The difference with the pictures on plug chart (thanks DMAN999) is that my plug looks smooth (the black part), the oil fouled plugs on the chart show the oily surface doesn't look as smooth.

If I put the bike on center stand (level ground), the oil level glass window is full of oil, all the way to the top. So If the my oil level is too high (which looks like it is). wouldn't all the other cylinders show the same problem? Why is it just on #3 only?

Other than the smoke when the bike starts, What other symptoms I should see with oil/valve problem?

I took a compression test today. The result WOT is 150psi for this #3 cylinder. Which is good I suppose. Cyl #1 is about 140-145psi. I didn't have time to check #2 and #4. (But I did the test with engine cold, I forgot to warm it up, and I didn't put any oil in the cyl)

My question is it possible to have a good compression with leak valve? How difficult of a job is it to adjust valve and change seal? Can any bike mechanic do it, or does it have to be vmax expert?

Thanks again
Regards,



If you look at this chart you'll see that your plug looks Oil Fouled:
http://www.4secondsflat.com/plug_chart.html

The smoke at startup could be Oil burning off.

What does your Oil level look like when the Bike is Level ???
If it's above the Top line on the Oil Sight Glass then you need to drain a little out ( I keep mine at 1/2-2/3 between the 2 lines).
If it's at the correct level you probably need to adjust your valves and check/replace the Valve Seals.
 

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If you can smell fuel it probably is which would suggest an over fuelling issue.
I should have said an oily skid mark - soot will do likewise but will be dryer.

The smoke on the RH side is probably some excess fuel that has leaked into the cylinder and is being burnt off.

Can you smell fuel in the oil?

Thank MaxMidnight, but what do you mean by smelling fuel in the oil? What oil? You mean the plug, yes, I can smell the fuel on the plug.

I tested the bike today with the AF screw on #3 turn all the way in (0 turn), but still the plug looked black again. Other than idle problem, the bike runs just fine.

So how do you fix an over fueling issue like mine?

Thank you,
Regards
 
Did yo ever get Ya problem sorted out? I had a similar issue with one of my cylinders on the left side of my bike not firing at idle and it turned out to be an electrical issue. Mine is a 85 and 2 out of the three wires coming off of the stator were broken in half. I know that may sound off the wall but I swear after I put new connections on it, not only did I solve my charging problem but now it fires on all for at idle. Mine seemed to effect the #2 cylinder though. When I revved it up past idle it would hit on all four but at idle only three.
 
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