Starter Solenoid Testing 101
By Mark Shively

Check the Starter Solenoid by isolating it from other components (disconnect small electrical wire). Check the primary winding by connecting a VOM (multimeter, Ohm meter, or continuity tester) to the small, 12 VDC wire. You should have continuity or little resistance (if any) when connecting meter test leads to the single wire and its metal body (ground) with engine off.

The larger terminals on the solenoid are tested by listening for the "click" sound when starter button is pressed while starting engine. What’s happening when you hear the click is the solenoid is an electro-magnet. When the starter button is depressed, battery voltage through the small wire creates a magnet effect inside the solenoid. This attracts the high current contact (a spring loaded T-shaped contact inside the solenoid) to travel upwards and connect with the two large exterior terminals on top of solenoid (heavy cable leads 10 gauge wire). When this connection is completed, current flows to the starter motor for starting engine.

Another bench testing method is to connect the solenoid's small 12 VDC lead to a 12 VDC battery source while grounding the solenoid body. Watch, feel, and listen for the solenoid "click and jump" when voltage is applied. This test verifies total solenoid performance.

High current contacts may become pitted or burned by arcing. This is normal wear. In severe cases, pitted and burned contacts may cause starting problems. The solenoid may be disassembled, inspected, and repaired, though internal parts are not sold separately. Disassembly requires de-soldering and re-soldering of the small wire from the solenoid cap, and bending metal retainer tabs before cap removal is possible. Once separated and opened, clean and file the contacts to restore performance. There are only a few parts to the solenoid; cap, body, T-contact, and contact return spring (not counting primary wire).

I prefer to use dielectric grease on electrical connections such as multi-connectors and bullet type connectors. Dielectric grease helps to prevent shorting due to rain and washing. It also helps to prevent formation of corrosion.

 

And another.......

When you hit the start switch do you hear a clicking sound from the start relay? If so, then take a piece of wire and then unplug the small wire that gos to the starter solenoid. Now place one end on the battery pos terminal, the other end touch the solenoid connect that the small wire was hooked to. (Make sure the bike is in neutral) Did the starter now turn normally? If so the problem is in either the starter relay, or in the start wiring from the start switch to the relay. In this circuit you will have two plugs that the wire runs through. Make sure the contacts are good. Also the wires to the start switch from the plug for the right hand controls are white and black and red and black Find these two wires and check with a voltohm meter set to low ohms. Put one probe to one terminal and the other probe to the other terminal that these wires are connected to. Press the start switch. ANY resistance indicates a bad start switch. If this check is normal then leave the probe in the black and red cavity and go to the start relay. Place the probe to this end of the black and red wire. With the VOM set for low ohms what is the reading? If ANY ohms is indicated check the wire back to the plug for it should read O ohms. If everything checks normal remove the start relay and take it to any auto parts store and pick up an identical replacement and install. Does the starter now work? If yes you found the problem. If no, take the VOM and place the black lead to ground and touch the red lead to the black and red wire of the start relay with the relay plugged in. Now hit the start button. What voltage did you read? If it was anything other than battery voltage you are dropping voltage somewhere in the circuits. Since ALL circuits are grounded through the main ground bus on the main chassis of the bike I would start there and check each individual wire for a solid connection at this point. Don't just look at them, examine them. If there is ANY sign of coorosion around the terminal(s) remove the wires and clean them up before reinstalling. If these wires are fine and are solidly connected then go to the battery ground wire and check to make sure it isn't cooroded even inside the insulation of the wire. Make sure that both ends are clean and solidly connected.

Good luck my friend, for an intermitent electrical problem can drive a good tech nuts, and cost big bucks in labor to find. And unfortunately, they don't get any better. Usually, once they start they just get worse. Samuel

 

Thank you Dawg for posting these tips. I've load tested both the old and new battery at about 200-250 Amps at the local Auto Zone. Both came out great. Now, I'll follow these guidelines and troubleshoot the Relay, connections, and the starter motor itself.

 

I have seen the contacts in the starter solenoid go bad to the point where the starter motor will not spin. The heavy click you hear is the solenoid moving the plunger to engage the drive and close the contacts.
You'll need to perform a voltage check at the large copper terminals while the start button is pushed. If voltage is present at 1 terminal and not the other then the contacts are burnt in the solenoid.
Sometimes you can remove the disc, clean it and clean the contacts with a little sand paper and get lucky that way.
If you really want to tackle this yourself I'd recommend getting a Maintenance manual and the Electrical troubleshooting manual.
Good luck and let us know how you make out.