not firing on #2

[littlejohn2458]

Buddy of mine pick up this bike for $400.00 got it running and all but not on #2.

1982 Suzuki GS1100K


Well, here goes

compression: #1 150, #2 150 #3 145 #4 150

Spark: HOT on ALL!

just cleaned the carbs, set the needles at 3.5 turns out. it started and ran half way decent on choke, kinda not good but still ran. took choke off died, tried to throttle it up died. re adjusted the needle setting to 1.5 turns out and it ran off choke but still no throttle response. just died. (the needles on top of the carbs to the rear. spose there fuel flow needles and not air like boats) anywho. was running it for about 2-3 minutes and noticed that the #2 exhaust pipe was not hot. kinda baffled. dont know what to do. the only thing that is different now, is that the little screen in the seat was torn and mangled to i took that off. would that make this big of a difference as to not make it fire? I was looking through all of the carb specs and did not see any needle settings for this carb. it said factory setting.

anyone know what the setting is on those or where a good start would be? also, any clues as to why it would not be firing on #2. he is using the plugs that came with the bike. They seems to be carboned up a bit but the spark was extremly good. pretty sure im getting fuel into that cylinder cause that plug was also wet when i removed it.


(i am a boat mechanic and new to the whole motorcycle carb deal. not used to the slides and all that.)

please help.
Thanks a ton,
John

[SqDancerLynn1]

If the #2 plug was wet you need to check the petcock vacuum line for gas.
IT WILL NOT RUN properly without the airbox. The tiny screens are not mandatory, use to catch garbage that may not allow the needle to seat

[BassCliff]

Hi,

I concur with Ms. SqDancerLynn1. You probably need a new petcock. Follow the procedures in your "mega-welcome" and you should be good to go. Did you really clean the carbs?


Thank you for your indulgence,

BassCliff

[littlejohn2458]

yes i really did clean the carbs. the slides were suck and there was a lot of crap in the jets.

[littlejohn2458]

wow i just now saw that carb cleaning section. I was not far off when i cleaned them. I did not take out the air jets in the front of the carbs. I got everything else taken care of though. those looked like non removable jets. ill rip it apart again i guess and see if they are clogged or any thing.

any luck on the settings of the fuel mixture? 2.5 turns?

[tkent02]

The initial screw setting doesn't really matter, you are going to fine tune it later once it's running.

[bwringer]

wow i just now saw that carb cleaning section. I was not far off when i cleaned them. I did not take out the air jets in the front of the carbs. I got everything else taken care of though. those looked like non removable jets. ill rip it apart again i guess and see if they are clogged or any thing.

any luck on the settings of the fuel mixture? 2.5 turns?

It's not the air screws and it's not the carbs. It's a bad vacuum diaphragm in the petcock. This allows gas to drip down the vacuum line for the petcock and make #2 very rich.

Before you fart around with anything else, replace the petcock.

(And sorry, rebuilding the petcock often doesn't work -- get a new petcock from your local dealer or your favorite source for Suzuki OEM parts.)