Bike won't run without choke

[radon]

The bike won't stay running without the choke on. Just stalls. Once its running I can shut the choke off quickly and give it some gas to keep it going above 4k or so it runs fine but then when i let go of the throttle it stalls again.

Replaced plugs fouled plugs because I ran it to long with the choke on. Done a carb clean myself following Carbs 101 didn't change anything. Had a shop sync up carbs and clean everything, still didn't change anything. Mechanic said the carbs didn't look terrible but made sure the pilot jets ( i think thats what they are called ) looked clear. Battery has a charge. The oil is a generic brand I found at an autostore for four stroke motorcycle engines. Fairly apparent the previous owner didn't take really good care of the bike. Has just over 50k miles so one of the previous owners did though. Mechanic said everything looked good except for the lack of being able to have a constant idle. Any suggestions? I have searched and lots of ppl have similar problems but I have tried their solutions without success.

Also the bike is a 1996 GSX600F Katana with 50k miles. Any suggestions short of a new motor would be greatly appreciated. Thanks

[md86]

Well , it sure SOUNDS like the thing ain't fueling properly at idle for some reason , which USUALLY means there's crap in the pilot circuit , not necesarrily the pilot JET .... Usually it's the 3 little holes near the front that are plugged , or the pilot needle/screw .

[radon]

where exactly are these three holes? do you have a picture and don't you think the mechanic would have checked/cleaned those?

Another symptom that I failed to mention was the bike with the choke on will run but have varying rpms like the motor never seems to settle down it just varies from like 2k - 4k.

I will have a look at the carbs for the three holes.

[Damian]

Even though the carbs are synched, they could still need to have the pilot screws adjusted. Do you know how many turns out yours are?

I did the poor man's jet kit this morning and tweaked the pilot settings. This made a huge difference in the idle problem I've been having. The screws don't seem perfect right now, but I'm sure I'm within a half-turn. They are 2 turns out right now.

Do you have the stock needle and jets?

Can you adjust the idle screw enough to keep it running?

[md86]

where exactly are these three holes?

Inside the float bowl is this little cirlce section near the engine-side . Plus the hole for the pilot screw . If you look in the engine-side carb thoat and push the butterflies out of the way , you'll see the holes on the floor .

[radon]

Just started to drill out the brass plugs to get to the a/f screws (those are also considered the pilot screws right?)
The two that I have checked seem fine (set to 2 turns out) but I need to get to the other two and check. I will play with idle to see if i can get the bike to run without the choke on. hopefully I don't foul the plugs trying to run it.

On a side note doesn't look like I will be riding soon anyway b/c of the weather. It snowed/rained lastnight and everything is slushy and a mess this morning.

[Black_peter]

Since you have the carbs out, hose everything down with carb cleaner. All the tiny holes you can get to.
Also carefully run those screws all the way out and spray in the ports, clean the tips etc. Be very careful of the washer/spring/oring set up. Get that oring pinched or damaged and furgettaboutit. Clean those ports then clean them again (did I mention cleaning them?).
Even after I disassembled and cleaned the carbs I had to get in there twice with carb cleaner!

I did the poor man's jet kit this morning and tweaked the pilot settings.

Can you fill me in on that? I don't know about this.

[Damian]

I did the poor man's jet kit this morning and tweaked the pilot settings.

Can you fill me in on that? I don't know about this.

I was talking about the technique of placing a shim under the needles and richening the pilot screws.

At two turns out, this has worked pretty well, but I think it's still a little lean at idle. I'm going to do another half or quarter turn out.

I haven't noticed any performance increase from doing this, though the RPMs drop back down to idle much quicker.

[The CyberPoet]

Nobody else asked, but I definitely will:
What air filter are you running?

Cheers,
=-= The CyberPoet

[radon]

The air filter is a basic oem cone filter. I also changed it recently when I found gas or oil inside the air filter housing.

[The CyberPoet]

The air filter is a basic oem cone filter. I also changed it recently when I found gas or oil inside the air filter housing.

Did you change with a Suzuki OEM filter, or with an EMGO, which looks virtually identical, but provides less resistance to the air and less filtration (if you got it from me, it's definitely the Suzuki OEM).

If you are unsure, the OEM filter has the number 20C00 molded into the plastic either directly above or below the opening, and a blue number/letter code (like 69V) stamped in ink on the metal if you remove the filter & turn it over. The OEM one will also have come in a box that said SGP, Suzuki Genuine Parts.

Also: which exhaust header are you using?

The reason I keep asking questions is that the wrong filter and/or exhaust can make stock jetting very weak (not provide enough fuel) due to poor vacuum-building at the carbs.

Cheers
=-= The CyberPoet

[radon]

The filter isn't a OEM one but I am pretty sure the exhaust is completely stock. I was actually thinking more of a vacuum leak that was causing a improper a/f ratio after the carbs.

[The CyberPoet]

Try slapping the OEM Suzuki air filter in there before you do ANYTHING else and see what difference it makes. My guess is that it will resolve your issues, or at least a lot of them.

Cheers,
=-= The CyberPoet

[radon]

Don't have the OEM filter anymore. It must have been thrown out sometime. I did the carb cleaning today and checked all the a/f screws and set them to two turns out. Does it matter what kind of carb cleaner is used to clean with? I used the cheap generic walmart brand. After the thorough cleaning, I ended up using the entire bottle, I put the bike back together and attempted to start it up. The bike fired and ran for a second and then immediately shut off and wouldn't start again or even fire. I guess it might be the plugs that are fouled not causing it to fire. It might have been some of the carb cleaner that initially started the bike and then it died when it tried to run off of gas.? Thanks for all your help guys.

[Special K]

Sure sounds like carbs to me..............if you get it running at all, spray carb cleaner around the intake manifolds and the air caps on teh carbs and teh vacuum lines. If it revs up - you've got leaks.

Tighten stuff down.

If this does not show anything, go back thru the carbs. they are tricky and EVERYTHING MUST BE near perfect!