78e left switch grounding

TimeMachine

SeventyEighte
Messages
696
Reaction score
708
Points
93
Location
Vancouver Washington
Hello.. So while poking around in the infamous cramped headlight bucket, hoping to spot an obvious "fault" and comparing two left handlebar switches to each other for condition, I've come up with a question. How important is it for that left side switch to contact, apparently grounding to the handlebar ? The steel contact looks like an intentional ground ? Why ? Symptoms if not a good contact ? Thx, -RT
 
Very important. Contacting the bars makes a ground connection through them over to the other switch assembly, which has the same tab type contact to pick it up. This is the ground for your starter button. Without it, the button won't work. That's why if you install painted bars, many times the starter stops working. You need to clean the paint off in those two spots where the tab on each housing contacts the bars. Then the ground can "flow" as intended.
 
Okay, I see now the two switches ground through the bars to each other then ? I was uncertain of the reason as the handlebars are of course rubber mounted. That is good ! I'll check both switches now. Thx -RT
 
The left switch has an actual ground wire running into the headlight. The right switch doesn't. The right switch is fed it's ground from the left switch through the bars. The two switches share the ground connection from the left switch.
 
Good to know ! today all I found is a very bad pink wire connection which turns out to be the horn (big deal right) a poor handlebar ground and dirty poor switch action. A few lightly rubbed wires in the bucket. No smoking gun for blowing a main fuse. Off to work now, thanks again -RT
 
5T, A quick question here. I am modifying my 78se and am eliminating the left hand control. Do I just need to attach a frame ground wire to the bottom of the riser bolt to complete the ground cycle for the right control housing? I am only using the kill switch and light on/off switch.
 
yup that's how yamaha did it for a couple years, a ground wire with a big ole connector to fit the bolt.
 
Time Machine, I didn't realize you were still having issues blowing fuses. You can't believe how many bare spots I found inside my headlight shell. Shorts can be so hard to find because of the intermittent nature of them. Hang in there, you'll find it.
 
Willis, if you're not going to use the start button, you don't need a ground to the right switch assembly. The other two switches in there (kill, headlight) don't use a ground. They cut (kill) or redirect (headlight) a power wire.
 
Back
Top