GSXR1100 Idle and Running Problem

[csmutty]

So I just cleaned the carbs on my 86 1100 and rejetted it using the dynojet kit and got it running. I got it running and it ran like crap. Would not start without ether and when it was running it ran like crap. It would rev all the way to 10 grand but on deceleration it backfired. When cold the throttle response was bad but it was better when it was warm. The worst was off idle. So I bought new plugs and when I pulled them the center 2 plugs were white and the outside 2 were black. So why were the outside so much richer than the inside which were really lean? I called my friend in Mass who has worked with these bikes and he said syncing the carbs. The only other possible thing that I can think of is valve adjustment. What do you guys think?

[gixxer72]

So I just cleaned the carbs on my 86 1100 and rejetted it using the dynojet kit and got it running. I got it running and it ran like crap. Would not start without ether and when it was running it ran like crap. It would rev all the way to 10 grand but on deceleration it backfired. When cold the throttle response was bad but it was better when it was warm. The worst was off idle. So I bought new plugs and when I pulled them the center 2 plugs were white and the outside 2 were black. So why were the outside so much richer than the inside which were really lean? I called my friend in Mass who has worked with these bikes and he said syncing the carbs. The only other possible thing that I can think of is valve adjustment. What do you guys think?

My old '88 was pretty sensitive to float level...
Intake boots in good shape?
Odd that the plugs read that way, possibly a weak coil? If I remember one coil fired 1and4 and the other 2and3?
When my valves got tight (and they did, repeatedly) the engine would turn over more rapidly than normal on start up, but it would run OK.

[csmutty]

My old '88 was pretty sensitive to float level...
Intake boots in good shape?
Odd that the plugs read that way, possibly a weak coil? If I remember one coil fired 1and4 and the other 2and3?
When my valves got tight (and they did, repeatedly) the engine would turn over more rapidly than normal on start up, but it would run OK.

Yea I forgot to say that it does turn over rather quickly. So it could be valves then as well as carbs.

[Pigman]

Did you sync the carbs and adj all the floats???? if not.....

[Woodsy]

check jet position on the carbs? are you at the proper amount of turns on both Jets? other than that, sync the carb

[csmutty]

Did you sync the carbs and adj all the floats???? if not.....

No the carbs have not been synced yet. I am going to bring the bike to my friend in Mass on Saturday to have that done.

check jet position on the carbs? are you at the proper amount of turns on both Jets? other than that, sync the carb

I am 2.5 turns out on the airscrew. What do you mean by jet position?

[csmutty]

So i found out the problem. The plug wire for the 4th cylinder was not connected to the coil. I tore the whole thing apart and found that the wire was barely inside the tube in the coil. Pushed it in and the thing ran good. Still need to sync up the carbs as the idle is a little iffy, but the bike runs strong now. Thanks for all of your responses!!!

[Slyder]

Well cool you found the problem, I was about to say synch the carbs as well. Definitely still have that done though, I bet it will run even better afterwards.

Do you think you knocked that wire loose while working on the bike? If it worked its way out, or those are originals, maybe replace them as well

[csmutty]

Well cool you found the problem, I was about to say synch the carbs as well. Definitely still have that done though, I bet it will run even better afterwards.

Do you think you knocked that wire loose while working on the bike? If it worked its way out, or those are originals, maybe replace them as well

Well upon looking closer at the wire it looked like someone used silicone to hold it in place, like it had been a problem before. For now I am going to use zip ties strategically until I can get a new unit. And yes I am still going to have the carbs done up. I can't wait to ride it home after that. I am going to check the valves this weekend too.

[Pigman]

Good deal......I would look it over and check every thing just to be sure..and Sync those carbs and tune it, she is a OLD beast. I luv the old sling shot 750's red and white with black