Cleaning and servicing the clutch switch
The clutch switch is a simple contact plunger switch. When exposed to dust and the elements, it can get clogged and grimy. If the contacts get clogged up with dust, the clutch switch could stop working. Most of the time, it just starts making really annoying grinding sounds and the switch starts offering resistance to the motion of the clutch. But if you get enough guck in the switch, the bike won't start with the clutch pulled in.
While you are doing this, be careful with the plunger on the switch. It's very easy to damage it, and you'll have to buy a new switch if you do.
Loosen the clutch lever clamp bolt (10mm).
You're going to twist the clutch assembly up, to get at the bottom of the clutch switch. Unplug the electrical connector before rotating the lever.
These two screws hold the switch onto the perch. Remove these to take the switch off.
The switch is only held together by the plastic clips on the housing. Here is one on one side.
And these two on the other side. These clips lift up by fingernails. A small screwdriver will also do it.
After the clips are pushed up, just lift up the housing.
And here is the housing wide open. The plunger is on a spring on the left. The right hand side has the contact plates.
Total parts are: 2 plastic case housings, 1 plunger with electrical wiper, 1 spring for the plunger return, 3 electrical track-style paths for the wiper to contact and the electrical connector. Use a small toothbrush and clean off the grit and grime that's in the housing. Then, move to a soft wire brush and then a pencil eraser to de-corrode the electrical traces (the copper bits). After the electrical contacts are clean, apply a small amount of dielectric grease to the traces, the wiper, and inside the electrical connector.
Put the plunger back in, then snap the two halves together and screw the switch back on. Use a strong wire tie or zip tie to hold the lever back while you reinstall. The plunger is easy to break. Be careful.