FZRSupport: the FZROnline Archive

Im in big trouble. I cleaned up my carbs (stock with everything), i lowered the needles by a level (now they are to last level), and i messed up with some screws. The screws below the gas level chamber were set at 7 and a half turns out and ai put them to 2 and a half turns out. I also messed with the screws between the carbs 1and 2, and 3 and 4 (i messed only with those 2, the one between carbs 2 and 3 is left as it was before) ,the ones that have some springs on them .I messed up with the screws between the carbs because i wanted the flaps that come over the carb boots to close and open at the same time.

Help me out and guide me trough the right way so i can make my bike idle again, because i'm going nuts.

What you are messing with are the syncronization screws.

There is a link in the wiki for a DIY (do it yourself) carb sync tool. Follow it, it is really easy and fairly cheap.

thanks CAD600, I understand that the ones that have springs on them are the syncronization screws. But what about the others below the gas level chamber ?

IMS (Idle Mixture Screws):

7-1/2 turns out is quite a bit. You can open them back up to 4 turns out and start from there. That will make the idle range fairly "rich" and easy to start. You'll need an IR Temp Gun to get them even. Fire the IR Temp gun at each header, aim about 2 inches down from the cylinder head and get about 2 inches away from the header (for an semi-accurate reading). Adjust the IMS till all of the temps are equal.

For those wondering where the IMS are located, here is an image:



**These are carbs from an FZR600 EXUP. That is why there is that funky tube coming out the bottom of the carbs.

Many thanks ragedigital!!!

One more thing, is there any other way to do the setup for the IMS screws, because i can't seem to find an IR temp gun anywhere near me? Can there be used any other type of thermometer? How high will the temp be on the headers when i will be doing the setup for the IMS screws?

If I recall, the temp will be around the 400-500 degrees F range at about 2000 RPM. The goal isn't a specific temperature, but rather making certain that each cylinder is close to the others in temp.

ragedigital wrote:If I recall, the temp will be around the 400-500 degrees F range at about 2000 RPM. The goal isn't a specific temperature, but rather making certain that each cylinder is close to the others in temp.

TFG,
As Darrin said it is equality of temperature that counts for road riding if you were racing them optimum temp for "the system" would need to be looked at.

There are diagrams for electronic fuel mixture meters on the web and I am sure that later model cars even by you have sensors that can be removed from the wrecks to be used.

Thanks for the answer YG. I have bought a thermometer that can be used up to 300' C. Is there a target temp that i should aim to have on the headers? I have also made a 2 bottle carb sync tool.
I have a problem with the tachometer too. The tach was dead and i took it to an electrician. He replaced a burned resistance (with the one in the image) and said that all the other parts are within specs and work fine. But now the tach goes up way too fast in comparison with the revs. Can someone please tell me what is the name of the original resistance that was in place of the one he pun in there, so i can replace it with an OEM part?

trifgeorge wrote:Can someone please tell me what is the name of the original resistance that was in place of the one he pun in there, so i can replace it with an OEM part?

I would take readings with this resistor & then use one double the value & see what the difference is

UNLESS some one has one open and can give us a value ?

The colour coding on the resistor (Violet Green Brown) indicate 750 ohms (if i have the colours correct). Double would be 1500 ohms (Brown Green Red).

Double check the colour coding here http://www.csgnetwork.com/resistcolcalc.html

Also top left of photo, looks like a variable resistor (plastic with phillps screw head marked J203R) could be for calibration. Try tweaking it slightly, and see what happens.

Thanks YG and Mawler.
Mawler, are those colors ( violet green brown) the ones that are on your resistor, or you refer to the ones that are on my resistor?

trifgeorge wrote:Thanks YG and Mawler.
Mawler, are those colors ( violet green brown) the ones that are on your resistor, or you refer to the ones that are on my resistor?

The ones on your resistor (photo)

mawler wrote:

trifgeorge wrote:Thanks YG and Mawler.
Mawler, are those colors ( violet green brown) the ones that are on your resistor, or you refer to the ones that are on my resistor?

The ones on your resistor (photo)

Mawler,
I think we are talking at cross purposes

The 750 Ohm resistor was a repair by T-George's as they did not know the right value of the burned out one.

Now their best guess makes the tach read too high too quick my best guess is it is too low and suggest they double that value (thanks for the link) and see what happens.

What we actually need at this point is some one who has an open tach to see the real colour code & tell us so we know what to drop in to get it working as designed.

did you ever discover the ohms of that resistor?

pulled my gauges and the resistor on mine is 680 ohms