1990 Katana 600 rough idle and bog around 3k

[Ashlander]

I was letting it run choked a few weeks ago to warm up and went inside. Got caught up doing something else and forgot about it, and came out about 15 minutes later to find that it wasn't running anymore. Probably flooded or something. But ever since it hasent idled right. The next few days it didn't idle at all, choked or not. I had to rev it to keep it running, as soon as i let go of the throttle it would die. Another few days and it now idles, but very rough. I have to keep it idling high, 2500-3000 or else it'll slowly drop in rpm until it dies. It's tough to take off from a dead stop from normal idle rpm as well because of the issue with low idling. Also now when accelerating it'll bog from about 3-4k then it'll be alright. I've tried running cleaner throught the fuel system twice, and spark is good in all cylinders. Anybody know have any advice on what the issue could be? Or some tests i could run to give you a better idea?

It's still very driveable, I've driven it to work the last few weeks since im waiting on some parts for my car.

[firefighter313]

have you did the basic check yet

air filter
spark plugs
oil level/ fuel in oil
whens the last time the carbs were cleaned
are you sure your getting good spark or just that u seen spark from the plugs
also are the plugs black or white or are the wet when u remove them?

[Ashlander]

have you did the basic check yet

air filter
spark plugs
oil level/ fuel in oil
whens the last time the carbs were cleaned
are you sure your getting good spark or just that u seen spark from the plugs
also are the plugs black or white or are the wet when u remove them?

The spark plugs were new when I got it last fall (says previous owner). I tried getting them out to look at them, but none of the sockets i have will pull them out. The wires were all getting a nice spark though. I just ran some seafoam through the tank and sprayed some cleaner around the outside of the carbs when I got it out in the spring and it was just fine. Dunno how long it's been since they were actually removed and thoroughly cleaned.

[Stumpy]

I'd clean the carbs out thoroughly, change the oil, oil filter, fuel filter, air filter and new plugs.

You'll need a skinny socket to pull the plugs if you don't have the OEM one. Absolutely vital bit of kit!

If it was idling for 15 mins, you may have cooked some things - I hope that's not the case!

[Ashlander]

I'd clean the carbs out thoroughly, change the oil, oil filter, fuel filter, air filter and new plugs.

You'll need a skinny socket to pull the plugs if you don't have the OEM one. Absolutely vital bit of kit!

If it was idling for 15 mins, you may have cooked some things - I hope that's not the case!

I just finished up with work since school is starting again so i'll find some time to do that. Where should the fuel filter be? I didn't see one in the line when i removed the tank.

I think it'll be fine. I've been driving it about 70 miles everyday for the last 3 weeks since it happened, sometimes stuck during rush hour and haven't noticed any problems except this.

[Stumpy]

Oh - yours is a 1990 - you won't have a fuel filter. One less thing to check

[firefighter313]

The spark plugs were new when I got it last fall (says previous owner). I tried getting them out to look at them, but none of the sockets i have will pull them out. The wires were all getting a nice spark though. I just ran some seafoam through the tank and sprayed some cleaner around the outside of the carbs when I got it out in the spring and it was just fine. Dunno how long it's been since they were actually removed and thoroughly cleaned.

The spark plugs being new last fall doesnt say much for them tbh. I change my plugs everytime i change the oil and with the choke being on that long there is a good chance u burnt them pretty bad.also as i found out the other day it doesnt take much to gum up the carbs..id take em out give them a full clean then sync them back up..u will notice the diffrence

And as for seafoam it wont work if u have a jet that is fully blocked..there is nothing better then a full cleaning..i like to ride as much as the next guy but sometimes u just need to park the beast n give her the tlc she deserves

[Maverick.Marq]

I just ran some seafoam through the tank and sprayed some cleaner around the outside of the carbs

[blitz2190]

no one every reads the stickies, huh? we've had this question almost everyday this week

[Stumpy]

no one every reads the stickies, huh? we've had this question almost everyday this week

Depressing, isn't it

[Maverick.Marq]

I wish when you sign up. it forced you to watch carbs 102 before you could finish the registration

[firefighter313]

I wish when you sign up. it forced you to watch carbs 102 before you could finish the registration

Thats not a bad idea..mechanics 101 would be dead tho

[Ashlander]

no one every reads the stickies, huh? we've had this question almost everyday this week

I think most people dont bother looking at the stickies because on most other forums the stickies are usually just general common sense guidelines for posting.

And besides, I didn't know if it was specifically a carb problem. Could've been spark plugs, wires, air blockage, bad gas, etc.

[Stumpy]

I do have to ask - how did you check spark if you were unable to extract the plugs?

[Ashlander]

I do have to ask - how did you check spark if you were unable to extract the plugs?

I was just checking that there was spark getting to the plugs. If not, I dont know what kind of distributor or coil setup these things have. Im use to working on cars. Luckily it doesnt look like i need to worry about that yet.