I have a 1980 twinstar 200...I put a new battery in today...I am getting power to the points...around 4 volts. If I use a screwdriver to the points I get the plugs to spark. If I try to start at the selonoid or kick starter I don't get the plugs to fire. Can anyone help?
Electrical help
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Clean the points, sounds like the contact surface is dirty.
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Is that with the points open or closed? If closed, replace the points, but if open, you have another problem, like a seriously leaky condenser.
I put the battery on charge all night...voltage at the battery is 6.77 and at the starter solenoid. Voltage at the green wire is 4 volts. I can put a screwdriver to the points both open and closed I get the plugs to spark...but when I spin the crank I get no spark to the plugs.
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So you are saying that, with the points open you have 4V? Or, is it 4V with the points both open and closed?
Also, are you using the screwdriver to short across the points from the moving arm to the grounded side, or to lift the arm to open them?
When I test the condenser wire I get 4 volts with the key on. I am using the screwdriver in between the two points as in when the gap is closed...spreading them causing the spark. It appears as the wire bringing power to the condenser is losing the power...
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Clean the points.
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This is a basic ignition system, which is how yours is arranged, but ignore the wire colors: https://i0.wp.com/www.ihcubcadet.com/forum/messages/106/29778.jpg?resize=640,361
As you can see, the condenser is connected to the points and coil, and is grounded, either through a wire to the frame/engine, or directly to the frame through its case when bolted down. When the key is on, the coil should have battery Voltage at both low-Voltage terminals, as will the condenser and points, assuming the points are open. When the points are closed, there should be 0V on the coil (-) terminal, condenser, and points; this allows current from the battery to flow through the coil, creating a magnetic field. When the points open, that current stops, and the magnetic field collapses. This change in field tries to keep the current flowing, but it can't, so creates a high Voltage in the secondary winding that is great enough to make a spark; it also creates a high(er) Voltage at the points, which spark too. The condenser reduces the strength of the spark at the points, so they last longer; it also slows the rise of the Voltage at the secondary, making for a longer duration spark through the plug.
You never answered if the 4V is with the points open or closed. Also, where did you measure that Voltage when you disconnected the condenser, at the coil or points?
As you can see, the condenser is connected to the points and coil, and is grounded, either through a wire to the frame/engine, or directly to the frame through its case when bolted down. When the key is on, the coil should have battery Voltage at both low-Voltage terminals, as will the condenser and points, assuming the points are open. When the points are closed, there should be 0V on the coil (-) terminal, condenser, and points; this allows current from the battery to flow through the coil, creating a magnetic field. When the points open, that current stops, and the magnetic field collapses. This change in field tries to keep the current flowing, but it can't, so creates a high Voltage in the secondary winding that is great enough to make a spark; it also creates a high(er) Voltage at the points, which spark too. The condenser reduces the strength of the spark at the points, so they last longer; it also slows the rise of the Voltage at the secondary, making for a longer duration spark through the plug.
You never answered if the 4V is with the points open or closed. Also, where did you measure that Voltage when you disconnected the condenser, at the coil or points?
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So, the points aren't really closing, or they should short the coil/condenser to ground. That, or the plate the points are mounted to isn't grounding for some reason, or the connection to the arm side of the points is done wrong. I'm thinking the points are bad, and the screwdriver is connecting the arm to ground when you stick it in there, making the spark when you lift the blade off the cam.
Referring to the above diagram, did you have the condenser disconnected from both the coil and points? Does the black wire connect the condenser to the engine case at the points cover, or to the points? Just to be sure you're measuring the correct part, the condenser is a small, usually round, metal-shelled component, about the size of your thumb.
BTW, if you put your general location in your profile, there may be one of use near you, who can come have a look.
Ok so I got new points...the old ones were pretty shot...I'm getting fire now but can't get the bike to crank. I'm getting 4.4 volts at the points. I have set the points to the proper gap. Can anyone help me get this thing cranked again. What do I need to check?
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