TOPIC:

I have a 2 volt drop between battery and coil and another two to three volt drop from the points to coil. It seems that is one big drop. Does anybody know what the voltage from points to coil shd be?
The bike is a 79 kz650sr. coils are aftermarker 3.4 oms

Post edited by: jltomey, at: 2007/10/23 15:43

I would think that the low power to the coils is more of an issue than the voltage from your points.

These are with the motor not running, but the ignition on. But don't have the bike in that condition for more than a minute or two. The coils can overheat.

From battery to positive side of the coil should be less than 1 volt when the points are closed. Should be zero when points are open.

From the negative side of the coil to the positive side of the points should be less than 1 volt when the points are closed. Should be zero when the points are open. (Negative side of the points are always grounded.)

When the bike is running, theoretically, the drops should be less than 1 volt, but due to the nature of the points turning on and off, the meter may be slightly innacurate.

There is only current when the points are closed, and that's when you are concerned with voltage drops. True 2v drops indicate bad connections or bad wires.

9~10 volts at the points is good. the 2 volt drop is to prevent unwanted arcing

the 2 volt drop from battery to the coils needs to be fixed. you don't want any voltage drop there

pretty sure that the condensor i there to stop the arching, if you are getting a 2 volt drop on the wire running from the points to the coil there is some wrong, those wires are like 18 inches long connected at the points then a bullet connector at the coils, there should be a very little voltage drop, like .2 of a volt or so. start by cleaning all you connections and inspecting the wires for corrosion.

trippivot wrote:

9~10 volts at the points is good. the 2 volt drop is to prevent unwanted arcing

Like Matt said, it's just a piece of wire from the coils to the points. A 2v drop would indicate a bad connection or wire.