Topic: i got no spark... words of wisdom?

[dakeddie]

I can't get my bike started... and I'm super bummed out about it.  It's a 750K3, btw.  Here's what happened.  One morning I rode my bike to church and there was a light rain.  When I was leaving, I couldn't get the bike to start.  I checked for spark on cyl 1 and there was none.  I figured maybe the kill switch was buggered, so i wiggled it a lot.. nothing.  Then i wiggle the battery terminals.. nothing.  Finally the bike just started.  I got home fortunately, but the next day I couldn't get the bike to start at all.

Here's what I've done... suspecting the kill switch was buggered, I took the pod apart and checked the continuity of the switch terminals.  There was continuity always!  No matter which position the switch was in.  There seemed to be continuity with frame ground always too.  Is there continuity between the black wire and dark green through the regulator?

I have the clymer manual, which has a wiring diagram that really should be printed in colour... it's very confusing otherwise.  In my diagram it seems like the frame ground is dark green and that the black wire is not connected to ground.  I've just found this colour wiring diagram in the FAQ but it's for a K1.  It's missing some things like the 'starter motor safety unit', but it definitely helps.

I'm guessing my problem stems from the short between the black and black/white wire from my kill switch, but wouldn't that just mean that the I wouldn't be able to kill the bike with the switch?  Shouldn't it still start?  And if the problem were a coil or one the of points, then I would still get spark on either 1&4 or 2&3, right?  I checked for spark on 1, 2 and 4 and there's none.

I'm going to check out the regulator and see if I can find the short, any words of wisdom?

[Bob Wessner]

Are you sure it isn't just still wet someplace in the wiring harness? I seem to recall a post very recently where the poster had the same issue (bike left out and it rained). He put in the sun, removed tank and seat and put a fan on it. Problem solved. Just a thought before you start tearing into too much.

[dakeddie]

so i checked everything, condensor, points, coils, regulator, kill switch.  it all checked out.  but as i was trouble shooting and trying to start the bike periodically, the battery started to die.  i was about to put the charger on it, when i notice that the electrolyte was low.

got some distilled water, put the charger on it for a couple hours and the bike started up.  it's funny how the battery can have plenty of juice to turn the engine over, but not enough current to make a spark.

the good thing about this whole ordeal is that i have an excellent understanding of the electrical system of my bike.

[78CB750F1]

Glad it works!  I have had the same problem on other bikes with batteries.  The only good part about it is when you realize your electrical issue is nothing more than a discharged battery...

[Jay B]

I've never heard of that on something with points ignition. Usually if it will spin with the starter it will fire. I had a Suzuki outboard once that did that though. The starter would draw the voltage down far enough that the EFI wouldn't fire. It would spin over great because it was a 2 stroke, didn't take much to spin it. Anyway, glad it was an easy fix.