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james2153

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Hey all, new to posting. I have a MSO 140 oil cooled don't know what model or anything.
i bought the bike a couple of years ago not running. no spark. i replaced the coil and the magneto, didn't know how to test them and apparently the cdi was replaced. does anyone know how to test the cdi?

any help would be greatly appreciated.

Thanks, James
 
the way to test a cdi is to check it on another (known) working bike.
you need to make sure the circuit is earthed correctly to bare metal on the frame
 
:welcome: to miniriders mate..

ok firstly can you tell us a bit more about your bike..

what sort of ignition does it have? inner rotor or standard magneto setup?

did you replace just the magneto or everything to do with the magneto?

couple of things to try if ya havent already..

disconnect the kill switch just in case its a problem..
try a different spark plug and plug cap, preferably one from a running bike..
make sure all the earths in the wiring are good and make sure the coil earth is touching bare metal...

as for testing the cdi, its easier to exchange it for a known working one..
 
does the kill switch work by closing the circuit or opening it? with the magneto im not to shur it had a few wires coming it. all the earths on it have been soldered to the one earth wire that goes to the magneto. as for what sort of ignition it has... im lookin on some forums to see lol.

thanks mate
 
i was having a fiddle today and its sparking now. but it is if the timing is out or something. i kick it over it backfires and the kickstarter kicks back. anyone have any ideas?

Thanks, James
 
do your valve clearances... if its running a standard stator, it's not possible to alter the ignition timing. valve timing can be out, if the cam has been installed incorrectly, and the cam timing is out, this will prevent the bike from firing at the right time, and can cause kickback...
however, if it's causing kickback, the timing cant be too far out, so i'd be suggesting it's time to set the valve clearances accurately.
 
i was gonna do the valve clearances but i think the timing is out. if i line the crank to tdc the cam is out about 45degrease. i should have some pics up soon. what do you guys think?
 
dont take the mark on the magneto as gospel.

cam timing @ 9 o'clock and usually magneto mark @ 12 o'clock, but if you have the magneto off then line the keyway up @ 9 o'clock..

rip the spark plug out and use a small screw driver and chase the the piston up the bore with the screw driver down the spark plug hole while turning the magneto anti clockwise, when it reachs it max height then look at the cam timing..
if its 180 out then roll the magneto around another 360 degree's till the piston is up top again...

might also pay to mark TDC on the magneto when you have the piston at the top
 
thanks for your help guys, i set the timing and valve clearances now. starts first time. but as soon as it starts it revs really high. it has a mikuni carb on it. where are the idle and air/fuel screws on it. there is a screw on the opposite side to the choke in one under the carby and one near the fuel drain tube.

help appreciated
 
the screw on the opposite side to the choke is the idle screw, the one underneath is the air/fuel screw and the one near the drain tube, is the drain screw...
if it's revving really high when it starts, i'd say your idle is set too high, or you have your carb slide in the wrong way...
 
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