Engine Kill Switch - Burned.

[Julio A.]

After an attempt to start the R65, My dad noticed smoke coming from the right combination switch. After which the R65 stopped idling and refused to start again. upon opening the part, I noticed the red kill switch was burned and melted beyond hope and the internal white plastic housing of both the starter and kill switch was damaged.

I did open up the combination switch assembly recently since the kill switch had a missing bearing on it before, making it unable to click; accidentally shutting off ignition when you hit a large enough bump.
I fixed it and was able to ride for a short trip before this happened.

I'm facing two problems right now:
•What was the cause of the heat build up
•Where the **** will I get a replacement assembly

[Barry]

I don't know where you would get a new switch but they should be available from airhead breakers.

The main current that passes through the kill switch is the current that supplies the ignition coils but on an electronic ignition bike that could be as much as 8 amps. A sustained 8 amps would be enough to cause your problem if the switch was not making a good contact.

Ignition circuits pass max. current when the engine is not running or at idle if it is running. Modern Electronic ignition systems have a cut off to limit  the amount of time at max. current and thus protect the coils from overheating . I think I'm right in saying that the early electronic module did not have this feature.

It's always good practice to not have the ignition switched on for more than say 30 secs if the engine is not running.

[zebedee]

I'm facing two problems right now:
•What was the cause of the heat build up
•Where the **** will I get a replacement assembly

You could try posting on an R65 forum and see if anyone has a spare?

For example, I have a very faded and worn left switch assembly, a brand new right switch assembly, and a near new right switch assembly that doesn't fit my left handlebar because I had a vague moment when I bought it...  1984 R65 twin shock, though I think they're all the same, let me know if you'd like photos to make sure.

Here's a search on ebay for the switch assembly.

[zebedee]

Postage to the Phillipines looks like about $15 to $20 depending how heavy the switch assembly is. (Au$1 = US$1)

[Julio A.]

Wow! Thank for the help!!!  

I could easily have one bought from ebay by my cousins there and have it shipped here.

[montmil]

Julio, you still need to confirm why the switch toasted itself. Plug in a new switch and there's a possibility it, too, might cook off on you.

While you wait on a replacement, check the harness for damage, shorts to ground, continuity, all that good stuff. Could have been the switch itself failed and caused the short. Maybe...

Get your volt-ohm multimeter out and play detective.

Monte

[zebedee]

Julio, how are you going with this; have you nailed down the original cause of the failure? And of course, should I be digging out my spare to sell to you? 8-)

Graham

[Julio A.]

Found the culprit, a wire got caught between the assembly; shorting it to ground. I did a temporary fix and it seems to be holding.

I'm still looking for a replacement. it'll be great if you could sell me yours.
 

[montmil]

... check the harness for damage, shorts to ground, continuity, all that good stuff. Could have been the switch itself failed and caused the short...Monte

Ooh, name it and claim it! Sounds exactly like my first bean can failure; pinched the can's harness between engine block and front cover. Finally wore through and stranded me w-a-y out in the country.

Wife, truck, ramp and beer = day's happy ending.

Monte