Sparks flying from my throttle pulley

Whats up guys. (Skip to bullet points if you're in a hurry )

This is my first official post! and sadly i can't find anything relating to it anywhere.
Here's my problem, it all started on the highway when after accelerating from 60 to 80 and letting off the throttle the bike felt as if it died, and i could only keep the bike running after a certain point of pulling the throttle back. It would let off a huge backfire and be gunning it. it was either full throttle practically or dead motorcycle. No idle. eventually under 20mph it died. Took it home looked at everything couldn't find anything wrong, Went and got a new battery and bam it started up again! Sweet let me take it around the block. As soon as i left my drive way and gave it gas it started shorting out and dying and running between throttle movements. i take it back home and a cable on the back end of my throttle pulley is throwing sparks when rubbing against the engine. where does this cable lead to?? and how much slack should it have. Thanks guys, i've been scouring and trying to find the name for this cable and what its purpose is and it gets lost under my tank.

BULLET POINTS
-Bike died while riding
-New battery fixed bike
-Now sparks fly off back end of throttle pulley
-What is the second cable connected to throttle pulley?

In this photo you can see its blackened from grounding out.

This is the cable at full throttle when its no longer making contact

Once again thanks for your time in reading the long post haha.
-E.

The only cables you should have on the throttle pully are the throttle cables!Some bikes have only one and some have two, one to open and one to close the carbs.
and from the photos its very obvious that one of your throttle cables is very loose. You need to tension it up or maybe its shagged out and you need to replace it.

No idea where the sparks are coming from unless you have a short somewhere in your electrical system,maybe a wire has rubbed through on one of your throttle cables.This could also explain the erratic running that you talk about .

If you lift off the tank,check the wiring for breaks and tension/replace the throttle cable(s).
Then see how it runs.Good luck.

(if youre replacing the cables,its a good idea to use the old one to pull the new one through.Then you know that its run is right and its not going to pinch or bind when you go round a corner.)

I saw this happen once to a KZ900 where, over MANY years of very lame ass maintenance, the two spark plug wire's insulation (on the right side under the tank) had rubbed through both the plug wires of 3 and 4 cyls.....and also, the vinyl sheathing on one of the push-pull cables of the carbs. Never seen the before or since.
That really created a horrible misfire and dead cylinders.
But sparks flying...? I'd pop the tank off and scope it out... should be obvious.
Or maybe the 12v up at the throttle control kill switch is shorting out to something through the push-pull cables?

It must be close or touching on of your spark plug leads. If it was 12 volt, you wouldn't see sparks.
Steve

Your cables are WAY out of adjustment! The manual shows how to properly adjust them; I wouldn't ride the bike until I had adjusted them. Ed

missionkz wrote: I saw this happen once to a KZ900 where, over MANY years of very lame ass maintenance, the two spark plug wire's insulation (on the right side under the tank) had rubbed through both the plug wires of 3 and 4 cyls.....and also, the vinyl sheathing on one of the push-pull cables of the carbs. Never seen the before or since.
That really created a horrible misfire and dead cylinders.
But sparks flying...? I'd pop the tank off and scope it out... should be obvious.
Or maybe the 12v up at the throttle control kill switch is shorting out to something through the push-pull cables?

hmmm i'll give it a good look, i was just curious as to what that second cable was. I'm sure its a similiar porblem here the bike was kept in a barn for a long time, had only 7000 miles on it when i got it. been slowly replacing things as they crumble haha.

Thanks all for the help, truly appreciate it. :side:

The bike has a push / pull throttle, that's why it has 2 cables. One cable is used to open the throttle, the other is used to close the throttle by twisting the grip clockwise. Normally the rider doesn't notice this becasue the spring on the carbs pulls them closed if the throttle is released. But if that spring should happen to fail when the rider cranks the throttle wide open that ability to close the throttle by twisting the grip can be a very good thing. :laugh: Ed

swest wrote: It must be close or touching on of your spark plug leads. If it was 12 volt, you wouldn't see sparks.
Steve

Well, to be honest, yes you will.
Try dragging a little wire across the positive and negative ends of your battery and tell us again you don't see any sparks at 12v... LOL.
Jesting... No don't do that.
With a measly 12v and all that amperage from a battery, you'll get a glowing wire and burn your hands right after you see all the sparks.

Check you handle bars switches. If you've had them off its easy to pinch a wire clamping them back down.

Out here Pack Rats like to chew on wiring and anything made of plastic. They'll steal shiny things and leave dog shit or something it it's place. They like to build nests in air cleaners and use Cholla cactus in their build. Reach in and get a hand full of spines. Nasty.
Look for chewed wires.
Steve

The wiring harness for the coils are right there so I'm betting there is a worn wire ..... I remember taping it up to the frame to keep it outta the way.