88 GSX600FJ outside 2 cylinders appear to not be working

[Askelon]

Im not sure whats going on with my bike. After I got new fuel yesterday and had done around 25k my bike stopped working properly - the two outside cylinders seemed to be starved of fuel or something - it would then surge then lose power again.

So far Ive replaced the plugs, that didnt seem to make a difference. Cleaned around the coils, pulled off the contacts and cleaned them up. It didnt make a difference at all. When I start it up after its been cold it'll start up on all 4, all 4 exhausts are hot to touch - roughly about even heat. Then when I start riding it'll start surging / losing power again. Im trying to find a real long screwdriver atm to try and drain the two outside carbs thinking maybe this'll help.

Anyone got any suggestions?

[scracha]

Swap the coils and see if the inside 2 cylinders exhibit the problem.

Older GSX's are famous for electrical woes, mostly due to stupid bloody design.

http://www.justanswer.com/questions/29cy6-own-1993-suzuki-gsx-600-believe

[Askelon]

Many hours later, 1 pissed off mechanic with no clue and I have it fixed :). He kept telling me dont waste your time on the carbs its electrical / spark plugs / blah blah blah. As soon as he left I pulled the bike apart again, pulled out the carbs and drained the buggers! 1 & 4 seemed to have a good buildup of crap in them, the others werent so bad. After assembling it everythings working perfect again. Im guessing its either the fuel I had gotten 20km earlier was either really filthy (not going back to that station ever again - Mobil in Glendene in case anyone wants to know!) or there was just a buildup over time - Im thinking the first myself.

Man the Harley was just sooo much more fun to work on!

[F5 Dave]

Possibly unintentionally you have fixed the problem. The crap in the carbs is likely from your rusting fuel tank. All suzukis of that vintage do that & a fine sediment of rust will pack like mud in the carb bowls. A decent tank sealant like POR or Kreem will stop that happening.

Can I bet that you have a fuel filter fitted? Or aftermarket hose?

These are not fine enough to stop the rust dust mentioned above, but they often can position the fuel line enough to crease it with the above symptoms. Seal tank & throw away filter &/or you can get right angle filters that help.