Idle problem

[38 special]

Sorry if someone has already asked this question but I'm in a hurry and I'm just going to ask for possible things to check. I put new plugs in my bike and it seems to run better and get much better gas mileage (I was getting 22mpg ugh...) I'm sure someone will direct me to a thread if they it was already asked. My problem is the bike won't idle. I found the idle screw and it works okay, the problem is the throttle will back off to much not allowing the idle to keep the bike running. As long as I hold the throttle in position it will idle but as soon as I let go it will back off too far and the engine will die. Dosen't matter if it's been running an hour or a minute. I have to constantly hold the brake and the throttle at a stop to keep the darn thing running. Sometimes I over rev too much and it looks like I don't know what I'm doing. This is especially when I'm on a hill. Makes a veteran biker look like a fool over revving trying to keep the old girl running. Any suggestions? I have no manuel on it and lots of these things were not on any of my old bikes. I've always had old bikes. They fit my current budget.

[onegunguitar]

You wanna make sure the throttle bodies are synced correctly.Also,you might wanna check things like the fuel filter plus the screen in the fuel pump and make sure you have enough fuel pressure,should be in the 36 psi range.If you're only getting 22 or so mpg's,it sounds like you may be running way too rich. I bought and use a Colortune kit-the glass top spark plug, to set my throttle position sensor to get the fuel/air mixture correct,makes life alot easier than guessing.I have been getting 34-38 mpg riding 2 up running backroads and cruising in the 60-70 mph range.Adding Nology Profire coils also made my bike run alot better. Hope this helped!

[Me Again]

Try adjusting the cables to take the play out of them.
Also check the clutch cable.If it's not fully disengaging the bike is trying to move pulling the idle down.
Then when it idles down just reach under and bring the idle back up to were you want it.
You may want to set the idle a little high until you can get it to stay put.
If you still have problems try the yahoo site and set the position sensor.It can be touchy but others have worked out most of the problems.
Good luck.

[38 special]

Thank you, thank you both.
I do think she's been running too rich. How do I adjust the cables? Is it the two lines that come out of the top of the throttle on the handle bars? I have tried to adjust these not knowing for sure what they did/are. The one on the right (the farthest from me) is already all the way to the end of the adjustment nearest the grip. That gives me somewhere to start. Much appreciated guys.

[onegunguitar]

One cable pulls the butterflies open and the other helps pull them shut,although they are spring loaded. On the throttle bodies,one is adjustable the other is not-if I remember correctly.You should have like 2-3mm of play at the grip,they can be adjusted at the handlebar as well,which you know. I highly doubt that is your idle problem because when the flies are shut the cable really does nothing then,if they were staying open then yea,the cable adjustment could be the problem.There is an adjuster screw for the high idle lever and obviously the thumb screw for normal adjustment. The throttle position sensor controls your air/fuel mixture which can lead to alot of things,but I'd say since your bike doesn't want to idle and has poor fuel mileage,I'd say that's the culprit. If you pop the cover off you will see two screws,loosen them and turn the tps-you will hear the motor smooth out or get worse,it's hard to get it perfect,but you can get close by listening and checking the plugs,this is where the Colortune plug comes in handy!!! Also,too much fuel pressure can make it run rich as well. My bike ran too rich when I bought it and thru trial and error and messing around I got it running pretty good. I just came in from a 30 mile cruise running 2 up at 60-65 mph and the computer was showing 40mpg(without that crappy ethanol mixed gas).Just be patient,read and ask questions,haha!! Here's a great site if you haven't already seen it-http://www.kz1300.com/tech.html There is a wealth of info on there.

[Me Again]

If you decide to adjust your TPS make absolutely sure that you mark it first.You need a reference point because you don't move it very far and may need to readjust.
When you adjust the cables loosen them up first.
Turn both nuts all the way in, the one closest to you is the advance . gently hold the throttle in a closed position and turn the advance until you feel the throttle turn , then do the same the other way.Try to keep the cables an even distance from center.If you turn more than 3/8 inch without feeling any movement ,switch directions to keep adjusters even .
Do not force the throttle to move . make sure when your done the throttle SNAPS back to idle position. If you force the adjusters it will not return properly.Adjust idle and your good to go. Others may have a better idea according to the book but this has always worked for me and once it's done you find your throttle is much more responsive .

[38 special]

Thanks again guys. That's a real help. I''l let you know how it works out.

[38 special]

Well I got to fiddle with it a little last night. I have it at least idleing now. It could be better but at least it doesn't quit at every stop sign. The idle is a little high but if I back off any more it quits so I know I'm not quite where it belongs yet but at least it's better. It's about 1400 rpms so it's too high an idle.

[Me Again]

I just resurrected one thats been sitting for 9 years and I have it idling at 1500.
I keep having to slow it down a little at a time the more miles I get on it.
I usually run just over 1000 anyhow just because they seem to run good there.

[38 special]

Mine seems to be backfiring a little not very loud just little bits. I heard it better when I rode without my helmet to go get gas. Just every so often. Glad you got yours going.

[38 special]

Well I don't have the bike back yet but I dd take it to a dealer to have their mechanics look at it. They said the plugs were fouled out. Hmm... I just put them in 3 weeks ago and I put about 150 miles on it since then. Also said the plug wires were to old. Hmmm... they looked okay to me but maybe I'll try to get new ones. They also said the gas tank had lots of rust in it and they may have clogged the carbs. Hmmm... I just had the tank off and drained it when we just painted it last month. Of course for 65 bucks a carb they will clean them. That's too much for me not working full time so I told them, I'll do it. I did it on my old 81 KZ 1,000 I use to have it shouldn't be any harder than that, just more carbs to deal with. After I clean them do I have to syncronize them?

[Me Again]

I did it on my old 81 KZ 1,000

The problem with that is you have no carbs.Fuel injection.
If all you hear is a little popping I would probably leave well enough alone.
Change the fuel filter and plugs and maybe the wires.If I remember your mileage correctly it may be time to have the valves set.$$.
Check your coils for signs of real old age.(cracks and such)
Run some injector cleaner threw it and see what happens.
Did you ever find a replacement for that right side bag?

[38 special]

Hmmmm... another hmmmm... I forgot it was fuel injected. Even the dealer said they wanted to clean my carbs. I'm getting suspicious of them.
I have run one can of seafoam through it but it still is doggy.
No still looking for right (curb side) bag. Not looking hard yet.
Maybe the plug wires will do the trick.

[Me Again]

Maybe the plug wires will do the trick.

You may want to look into a set of coils also.
There are some less expensive alternatives out there.
Check the yahoo site and ask about the GM coils