cb200 not running -cam 180 out?

Bert Jan said:
I gave it some fierce kicks full throttle. Plugs are dry. I suck for not checking that before. Sorry!
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Sounds like you have a fueling issue. First up, don't try to start with the throttle open unless you know you're already a bit flooded. It's extremely difficult to start a carbed bike with the throttle open because you can't kick hard enough to pull enough air for the main jet to work.

Try ten more kicks with the throttle closed and see what the plugs look like.
 
Checked carbs, they're ok. Plugs are wet now aswell after kicking it couple times.

edit. posted this before previous post. gonna kick it 10 times closed throttle now.
 
Time to pull the carbs.

First thing to check is to see if there if fuel in the bowls. There should be, provided your petcock has been on. If you have a vacuum-type petcock, it should have been in the "prime" position for starting and then switched to "on" on "run" after the bike is goind.

Next, check to make sure the slides (or butterfly valves, if your carbs are CV types) are open slightly. There should be a screw on the side of the carbs that adjusts the idle. This idle adjustment works by opening or closing the valves/slides a slight amount. If the screw is adjusted so that the slides/valves aren't open just a little bit, the bike will not start. They only need to be open a very little in order to work.

Finally, if the first two things check out OK, you'll probably want to pull the jets and give the carbs a decent cleaning. Something is likely blocking up the carbs. Admittedly, this would be rare to have both carbs blocked unless they have gone a long time without cleaning or have been sitting a long time without the bike running.
 
Both carbs and all needles are clean as can be, have fuel in the bowls and the sildes are open just a little (light is barely shining thru). Could it be a valve issue, i mean, they need a vacuum to suck up mixture. When valves are open when piston goes down, it's not working right? But, as my cam is correct and my valves still straight :) i guess that's ok.

Im getting very confused...
 
Im not running a tank but 2 hoses. I can see the gas going down when i kick it. Gas aint going to cyberspace but i don't know where if the plugs stay dry and the fuel goes down..
 
intake valve should be open when the piston is moving down, and close a little after it starts moving up again, exhaust should be closed from slightly after piston starts moving down to long after the compression stroke is through, if you have compression in both cylinders, it's indicating the valves are closing and opening at the proper times.

describe how you set the valve clearance in detail.
 
I took off tappet covers and rotor cover.
Turned rotor at 'T'
Looked wich (left or right) intake valve was closed.
adjusted that one at 0.05
adjusted corresponding exhaust valve at 0.05

turned rotor at 'T' again
did the same for other cilinder
 
Let's back up a little. Full throttle kicking only works if the engine is flooded. Low air velocity doesn't pick up any fuel from the jets. OK for flooded motor - no good for normal starting.

I would pull the carbs and check the small holes in the carb at the front of the slide. Remove the float bowls and blow through the pilot jets. You should see fuel spray out of the small hole. Next spray from the filter side down each of the two air holes. The pilot (no jet) should blow out of the pilot jet and that hole in the bore. the brass air jet (main air jet)should spray out of the main jet and/or the needle jet. Check that both carbs are the same.
 
I did my 550 top end couple years back and been wrenching on bikes all my life, but i don't get this one.

Ok so now i have fire on both plugs, compression fo-sho as its been honed with new rings, but fuel won't come into the room. I've set the needles inside the carbs one notch higher. I thought it would suck up more gas that way. Still no fire, not even an exidental late misfire. No nothing.
 
It has to be something simple that we're just not thinking of. Did you try Starting Fluid down the carb throats to see if it fires up on that?

Is the cam correctly timed? Easy check is to watch the intake and exhaust valve on one cylinder at say 20 degrees either side of TDC on overlap. Turn the engine over TDC and the valves should open/close roughly the same distance either side of TDC.

Are the slides in the wrong sides with cutaway facing the valves instead of facing the filters?

Is there fuel in the float bowls when you took them off and was it roughly the same amount on each side?
 
definitely try the starter fluid, it will eliminate the fuel variable if that's the cause, like teazer, i also wonder if the cam is off a tooth or two, that may not be enough for valve contact, but enough to make it impossible to start, what were your compression numbers? they may indicate an off cam
 
The cam is correct, as at TDC the notch on the cam is either at 12 or 6 EXCACTLY.
Slides are in with the slanted side facing the filters.
Going to get some starter spray now, back in a few
 
Tried with starter fluid, still nothing. Not even a "poef". Installed new spark plugs also, just to be sure.
 
This makes no sense. Is it possible that the spark is too weak. Maybe it looks OK in fresh air, but has not enough power to light the fire under compression?

Try another coil to eliminate that possibility and replace the condenser.

Try to bump start it. Sometimes a rebuilt engine takes a long time before it will fire up. I have had that situation several times
 
I dont have a chain and sprocket in yet as this is a complete rebuild. I soldered every wire (instead of plugs to eliminate corrosion) and just installed new wires. I have a battery straight up to the coil and frame and use another battery to start. When i spray jump starter in the carbs it gave a little pooef.. but that was is. Going for another coil. I have a cb125 coil wich looks the same. Going to put it on right now.

Thanks for the help guys, its driving me crazy and you keep me going! Love (nohomo)
 
i installed the 125 coil and the spark is about the same. There is a big fat spark (wich would normally be at the plug) on the points however, and it doesn't matter wich coil i use. The points spark like crazy.
 
Spark on the points is far more intense that at the plugs. Actually the spark at the plugs is hardly noticable.
It does not matter wich coil i use. The spark is the same with both.
 
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