93 Suz Kat 600 - No spark etc. -- Like to read?? - Motorcycle-Journal Forums

BenchFalco · 11-11-2004, 10:13 AM

I have a 93 Suzuki Katana GSX 600 F. I bought about a year ago and have been tweaking it constantly since it was in a state of disrepair when I bought the bike. Since I love working on bikes this is great. However things get frusterating when I don't know how to fix a problem or improve performance...I hate not being able to solve a problem myself, and I would rather get help from experts (you folks!!) which are riders just like me...so here we go....afterall, what's the fun in having a bike if you can't take your favorite girl for a ride?

PROBLEM: The bike won't fire, it won't even try to fire. No cylinders have spark. I have tested the electrical system front to back, everything was well withn spec.

Here's some info on what I did so far: I used an ohm-meter on each of the two ignition coils (checked all 4 plug wires) on the bike. These coils (and wires) checked out okay. Then I compared those readings against another pair of coils (with wires attached) and had the same readings. Great I thought! It's not the coils....next step. With the ohm-meter I checked the CDI (Black Box) ...no known test...so I swaped out the box for an identical one and checked the circuits which pass through the ignitor (checked both boxes) and got the same numbers so I move on from there. Still with the ohm-meter, I checked the resistance in the pickup coil that sits next to the signal generator rotor. This was within spec too.
The electrical system seems to check out. So I think that the only problem could be the actual rotor itself. But I cannot see how such a unit could wear out as it doesn't actually contact anything. OR, maybe there is a relay or something in this circuit that isn't performing up to snuff.
WHAT COULD THE PROBLEM BEl???

Heres a little background info about the ongoing trouble the bike seemed to be exhibiting:
1) When I (attempt) to pull away from a stop the bike had a tendency to hesitate. I figured it was a carburetion issue, or dirty plugs. "Strange I thought" Since I literally just tuned and cleaned the carb and installed new plugs. Then after I get into higher rpm the problem dissipates. This seems to indicate that the battery was weak and not generating sufficient charge in order to fire the plugs. I know that Katana's have a battery-dependant ignition system, which require a good battery for proper operation, especially in low rpm. SOOOO.. I got a new battery -- didn't fix the problem.
2) After/during a rainy day the bike runs a little more poorly than usual. Once it would not start at all after running perfectly. I figured it was some moisture grounding the spark inside the rotor housing (gasket needs replacing). After leaving the bike sit and for a few days (in dry weather) startup was no problem....but it ran okay in the rain after that....?!!?!?
3) Finally, before completely quitting, while riding the bike began to lose power, like only 3 cyls. firing. Then after 20-30 seconds the problem dissapeard. I guess this means that the rotor isn't generating power....

So with all the info above, WHAT COULD THE PROBLEM BE?

Also, I have a rebuilt carb (ebay) with a stage three kit installed and new K&N's. The carb has been sitting for quite some time as I am preparing to swap out my old for "new". Should I consider replacing the rubber gaskets or float bowl seals? I am somewhat concerned that they may have degraded after sitting for XXXX amount of time. What has been your experience with this type of situation?

I would appreciate any tips on squeezing out more power from this HEAVY-ASS 600. The frame is all steel and the sticker on the frame says that the Wet Weight is 925 pounds. Does that figure make sense to you folks?...I'm thinking that afterall I do have to wind this sucker right out and clutch it to get the front wheel off the ground...

All the obvious stuff has been dealt with. Valves adjusted properly, clean air filter. All that's left is perhaps the fuel delivery system. But I have never had a problem here........

ALSO I grounded a spark plud against the frame to test for a FAT-BLUE spark. All I got was a tiny, barely visible white spark. This would indicate that the problem is DEFINATELY ELECTRICAL .... right?!?!?

I'm assuming it's the signal rotor and pickup coil....

IF ANYONE COULD IMPART SOME WISDOM ITWOULD BE MUCH APPRECIATED -- if you have time after reading all that!! THANKS

Keep it between the ditches
-B