One last cry for help

[benchfalco]

This has been a problem since September 2004....maybe someone put a curse on my bike.....I've posted this before, and seem to be a making a little progress (no spark has become "some" spark).....

1993 GSX 600F Katana

Problem: Minimal Spark, almost none....I would assume a bad wire somewhere, but I swapped out an entire wire harness and the problem still persists.

I've studied wiring diagrams and followed the pathways, everything seems to be great (I'm obviously missing something.....). I performed all known (resistance) tests for the signal generator rotor pickup coil, and the ignition coils --- both coils and pickup were A-OK.
SpecialK tested a pair of my CDI's, "both are great" according to him, so the problem isn't there....

Battery is brand new, fully charged.....

I cleaned the ground connections....

The bike was running "fine" before it quit BUT the final weeks leading up to electrical-death she would hesitate from a standing start (low rpm) and wouldn't REALLY snort until the rpms increased (bad alternator...or regulator/rectfier within??)) --- I chalked the hesitation up to a dirty/improperly adjusted carb, but oh wait....I fixed that stuff earlier in the season. -- (the hesistation still could be a carb issue since I'm not an expert)

The day she finally left me....I was riding and the bike lost power (it felt like....say, only 3 cyls firing) and after maybe 5 seconds the problem went away, power returned to normal, I rode the short trip home, parked her for the night, and that was the last ride I ever had; she was lifeless the next day; never spoke to me again.

I am really at a loss.

The only other information(s) that might be relevant at all is:
ONE that the previous owner had the rear signals makeshift wired (jammed a raw wire into the fuse box signal fuse circuit)...this caused one blinker to flash slightly more rapidly than the other....(it has been that way for years with no problem).
TWO, there was an incorrect sized battery installed when I purchased the bike; it was larger (battery holder was modified to fit it) but the same voltage (12V) now I have the stock size installed.
THREE the highbeam indicator seemed to work intermittently, on sometimes, off sometimes (with highbeam on ) but the ACTUAL highbeam/lowbeam works fine (I figure a bad filament in the indicator bulb).
FOUR She quit the day after I returned from a LOOOOONG ride with a buddy. We rode a few thousand Km over a few days; hours on the bike per day.....

I don't know if any of that info is useful at all .....

Oh well, at least I had time to do some painting and fab up some frame sliders (3 per side) -- will post pics once she's back in one piece.

I'm looking for some real help on this one..... I've been to hellandback, and I'm thinking about revisiting.

Thanking you all in advance (again*again)

[pmkls1]

well just to put in my 2 cents worth I would definately check for a problem with the generator as it seems you have all of the other points pretty well covered. I dont do a lot of motorcycle work other than on my own so I would think that a bad generator would cause a no start situation but since they have such small electrical systems it is very well possible. I dont see any relation to the other electrical problems though. it would be nice if you at least had a working generator to try out just to eliminate it. but as a final question are you sure you have an electrical problem and not a carb or compression problem ???

[benchfalco]

when I ground the sparkplug against the frame or engine to test for spark there is a only a barely visible yellow/orange spark arcing on the plug......when it should be an aggressive fat-blue spark

both ignition coils (and all four plug wires) deliver the same result, so that leads me to conclude that they're still good (it's unlikely that both would fail simultaneously - right)

[pmkls1]

well, you also need to check for fire with a spark checker and not just a plug. it is unlikely that all 4 plugs are bad or both coils are bad but it still isnt impossible. also how much resistance do you have on the coils ?

[Katana Kid]

I can only give you advice from experience..... hook up a voltmeter to your battery. While its hooked up start moving wires around, look closely at all connectors see if the voltage increases. More than likely its something simple.

goodluck,

KK

[FTGRET]

Check to make sure that you've got battery voltage to the coils. Could be a bad connection.

[benchfalco]

thanks for the help so far -- I'll look into those things. I especially like the 'move wires around' advice -- I'll have to try that.

The ignition coils resistance test indicated that both coils were good, going by memory (I was last summer) I think the resistance was like 2-3 ohms, but don't quote me -- in any case, I know that the coils were good since they definitely checked out to be within the specified range. Thanks!

[donmega]

You can run a new pos from the battery to the coils if you want to eliminate a possiblity, all coils that I know of are negative trigger so the pos is always a direct connection.

I also didnt see ur plugs posted, I hope their NGK.
Rule of thumb if its forein NGK american Bosch
Stick to those rules and ur good.

[benchfalco]

nice tip with the pos direct connection!! --- I am DEFINITELY going to try that!!!! the plugs are NGK, DR8ES

[donmega]

How do you know the ignition is weak anyway ?

[kiba]

What's the gap on the plugs? Should be between 0.024 and 0.028" (0,6 - 0,7 mm)

/kiba

[benchfalco]

plug gap is good

I believe that the ignition is weak because the spark was not performing as intensly as it should have been --- it doesn't spark strong enough to ignite the fuel

I tried some 'quick start' spray today, and it seemed to kick over --- that was with the carbs removed, spraying directly into the combustion chamber.

I'm going to put her all backtogether and hope for the best....there is some spark, but it just seems minimal compared visually to other sparks from other machines, and I haven't tried to run the bike since the spark returned (it's been in pieces) so maybe I went through all these questions uneccesarily....we shall soon find out!

[benchfalco]

we did it! she's running great --- just need to sync the carbs, and put her back together; will be riding soon!

[md86]

So what's the story ?

[benchfalco]

story? my bike wasn't running, now after lots of help from everyone, it is (running at least) -- running well.


The problem I believe was initially electrical -- the problem was a broken magnet behind the pickup coil, and/or a bad wire (wire harness was swapped out) --- also the "minimal spark" might not have been so minimal after all (it sparks enough to run at least)

I also installed a new carb setup, and the bike sounds way lower now than it used to -- I'm hoping that this is only because of the new carb with stage 3 jets, and not a side-effect of minimal spark....

time will tell