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Discussion Starter #1
okay, so at first, i only had a slight hesitation as soon as i rolled on the throttle from idle.

but since bike week is here (i live 15 minutes from destination daytona), I have been riding ALOT.

sooo.. i start the bike today morning, and the idle is hanging up at around 3k when i rev it.. I took the tank off and noticed that in front of the air box is 2 nipples.. one is blocked off, and one goes to something right in front of it.. Something of concern or no?

The strange thing is- the idle sometimes goes down when i switch the headlights on.. electrical? or a vac leak?

all of my buddies that got sport bikes want to go on a ride in a hour.. Help is much appreciated.

Thanks
-Dom
 

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Does it ever come back down?

If it does, its probably lean as hell. Try it with the choke all the way on. If that improves things, then there you go. This usually means a leak in the intake system somewhere. Either the vac lines, or the carb boots.

If it just stays there, then turn down your idle with the black knob on the left hand side of the bike, that will close the butterflies a bit and choke down the air a little.

As for the nipples, its likely that you have the kleen air mod done to the bike. This removes the emissions BS under the tank. You don't need it anyways, unless maybe you are living in cali (you are not).

The blocked one... should be blocked. The other one should run DIRECTLY to the carb vent. There should be nothing else under there aside from your ignition harness, a big piece of plastic covering the front of the motor, the reed valve covers (which should connect together - the rectangular covers on top of the motor), and that single line from the carb vent to the front of the airbox.

If you do however still have the vacuum valve in place, but the secondary part that connects to the reed valve plates is gone, then you can/should remove that air valve assembly. My bike had a halfassed kleen air mod done where that was left in place with the vac line from #3 still ran to it. Then the other hoses that come off it were left disconnected. The bike ran like ass.



All four of the vac ports under the carbs should be either blocked off, or running to each other.

It is possible that there is a leak in the lines (if they are ran together) or a leak in the plugs, if they are plugged individually.

Also, make sure your crankcase vent is properly hooked to the port at the back/bottom of the airbox, right below the carb intakes.


As for the idle dropping, these bikes have garbage ass electrical systems. If the voltage drops just a little bit, it can translate to a whole lot of a drop at certain components.

As long as the bike continues to run, ignore it and consider yourself lucky. And welcome to the electrical shenanigans club.
 

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Discussion Starter #3
okay.. so when i put the choke to the on position, the idles goes all the way to 6k and stays there.

as for the vac lines- 3 of them are connected, and one has a hose that goes all the way to this thing in front of the air box...

and that black knob that you speak of.. well the previous owner gave that to me in a zip lock bag, stuffed in the trunk lol.. i need to use pliers to adjust the idle..

can you define the carb vent?
 

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Sounds like your PO was an idiot like mine.

That black knob needs to be connected to the bottom of the center of the carbs to adjust your idle. You need that.

The one that runs up to the "thing" needs to be blocked off, and the thing removed.

Then, run the second... you know, here.

http://www.zx7rmods.co.uk/#/clean-air-mod/4551020810


You can do this entire mod with pieces from the bike. I used one of the pieces of larger hose that fits inside the hose from the carb to the airbox like in the guy's first pic, instead of brass tube. Cut it about two inches long, then shoved it in to connect those pieces.

Then just make sure to block off that vac port.

The only thing I can think of is that the PO halfassed this, otherwise both of those front ports on the airbox would be connected.

And put that idle screw back in.
 

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Discussion Starter #5
okay, so the rpms hanging up is fixed.. it was a small vac leak..

now i just cant get it to idle right.. once i set it (the screw is in there, the cable snapped), it idles fine, but sometimes idles too low and dies.

im not sure how this would be a electrical problem since its carbed, but the idle goes down a little when the fan and headlights are on..

How often do you need to adjust the idle with that cable on the left side of the bike?
 

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All the time, until you get it set properly.

And it should only be adjusted while the engine is hot.
 
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