Left Handlebar Switch
By Chad Hancey
The wiring diagram on the website was accurate and matched the color coded wires perfectly with the exception of the orange wire which was noted on the diagram.

I began by removing the two Phillips head screws that secure the switch to the handlebar.
After this I cut all the wires (they’re bundled together in black tubing) coming out of the old switch and set the switch aside for reference.
I then pulled gently on the wires where they fed into a hole on the bottom side of the handlebar to ensure I could identify the correct wire bundle to cut coming into the headlamp bucket (there are several).
Once I was certain of the wire bundle I cut it as close to the bucket as possible.
With the bundled wires free I used pliers to grab hold of the bundled wires coming out of the handlebars just above the bucket and pulled them through.
I thought of taping the new wire bundle to the other end BEFORE pulling it through but the resulting wad of wires and tape wouldn’t have made it through without getting stuck or otherwise damaging the new wires.
I then used ONE of the old switch wires and fished it through the handlebars from the handgrip end.
This took some time to get it past the junction of the left turn signal and then through the hole above the headlamp bucket. Be patient – it can be done.
With the fish wire in place I tied it off to the new wire bundle and wrapped all the loose ends in duct tape before pulling it through.
Use the duct tape sparingly to keep the wire bundle as small and tight as possible – I even used a small amount of WD-40 to lubricate the wire bundle.
Again, it took some time but BE GENTLE.
There can be some sharp edges on the holes in the handlebars that could damage the wires.
This was the most difficult part.
Once the wire bundle was pulled through I salvaged some of the black tubing to cover the exposed colored wires just above the headlamp bucket and fed it carefully into the bucket.
With the cut ends of the OLD wires still in place it was just a matter of pulling them out one-by-one and matching them with the new wires.
The only exception was the OLD ORANGE WIRE matched with the NEW BLUE STRIPED WIRE (noted in the wiring diagram on the Beatrice Cycle - DrATV website).
The new switch housing was a bit too small to clamp around the handlebars without a noticeable gap between the two halves.
Also, I removed the wire clamp inside the switch housing since it didn’t serve any purpose and actually made the fit even more difficult.
Some grinding on both sides of the switch housing with a Dremel tool took care of that.
Also, be certain to have the correct light bulbs in the turn signals or the flashing mechanism will not work.
The switch works like a champ!
Editor's Note:
DrATV's web site mentions this switch replaces OEM parts for CT90's, 1975 (K6) up to CT110's, 1986.
Right Handlebar Switch
Ignition Switch
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