Hi, my 97 ZX-6 is intermittently missing. It does it sometimes and not others... it mostly did it at around 3,000 rpm.. Then one day it did it the whole time on a 40 mile ride. The local shop could not figure it out.

ANy ideas?

 

Carbs were checked out?

 

Yes, carbs completely drained and gone through, synced, etc.. A buddy of mine said to check the cam position sensor, but these don't have that. It's just pulsing rotor instead. I think.

 

If the carbs, boots and lines all checked out: A short or bad ground can cause you issues.

 

Okay...what do you mean by missing exactly? Describe what it is doing. Did you see the post below this one? And is your problem the same?

 

I see that thread now, haha. It is not the same. But it's hard for me to describe the issue. Today was my first ride in weeks... the bike did great for about 10 miles or so around town. Then it began. When it's "doing it" it will usually be from a stop.. I have to rev higher than normal and slip the clutch to keep from killing it.

When it does it at higher speeds, it it's often when I accelerate. It will stutter and miss, then smooth out. (that one day, new year's day, it NEVER ran right. weird. I took it the dealer then next day and it didn't act up ONCE on the way there. they had it for a few weeks and couldn't find a problem, though they were able to ride it and experience the problem.)

The dealer took all the carbs off and drained them, inspected them, etc. They are comfortable with the state of the carbs. So they say. That's the thing that's irritating.. SOMEONE has to hear this and go "oh yeah, that's the such-and-such."

The bike has under 12k miles on it, I use premium fuel of course. I'm only asking for help because my local dealer can't handle the issue; otherwise I have no trouble taking it somewhere where there may be a greater depth of experience.

 

i'm willing to put money on an electrical component.

meter your trigger coil with the motor cold. then, run for 10 minutes and meter it again.. should still be within a few % of the cold value and withintolerance or the kawi specified range..

next go to the CDI and the coils and do the same.... does it do it cold, hot, anytime, only when warm??
if it only does it when warmed up, go buy a can of computer duster stuff, and spray the components.. hold the can upside-down, this will cause uber coldness to exit the can, thus cooling the component being targeted.

if it stops acting stupid upon spraying, you've found your thermal defect.

also, if it does it without a load, (like in neutral) put the bike on a rearstand, remove the tank, run a line for gas (or sit the tank to the side) and run the bike til it starts acting up. at this point, pull the #1 plug wire (clutch side, or left when sitting on the bike).. note the sound difference.. do this for all 4 cylinders.. if you find that #3 makes no difference in the sound or missing, you've found the culprit cylinder..

be super super careful not to set yourself on fire or shock the shyte out of yourself, please? the spark should be able to jump a 10MM gap.. it'll reach out and touch ya bro...

you may have to do this several times to get a trustworthy base of faults and finds.. you want to rule out pulling a plug on a good cylinder, and it coincidentally misfiring on you..

like drag said.. carefully inspect the sparkplug boots for cracking, hardened/burnt rubber, oil, water, discoloring.. ect. listen for an audible "snap" during the misfire. ths will indicate a direct fire to the head, valve cover, or other source of ground..

good luck, and welcome to KF!!

keep us posted!