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Need help with my 2000 r6

4K views 15 replies 6 participants last post by  CBR240 
#1 ·
Keeps flooding out so i replaced my float needles an when i turn the key the fuel pump just clicks really loud an pushes gas in the carbs so it still floads out their is a pressure relay in the fuel pump that is makin the noise
 
#3 ·
Okay if i start the bike let it run for a min turn it off an then try an start it again it wont start but if i unplug the fuel pump it will start so im thinkin their has to be a persure relay somewhere bc if the bowls are already full from it ruing an then the pump is pumpin more gas in the bowls so the gas is just pushin though the shut float needles bc i just replaced those with new ones
 
#4 ·
Does the pump run every time you cycle the key? If you turn it on does it stop, then if you cycle it off/on again does it run again? It shouldn't if the bowls are already pressurized.
 
#7 ·
Check the float levels then. If their too high the needles will never cut the fuel flow off.
 
#9 ·
The little metal deal the float needle hangs on has to be bent 1 way or another to raise or lower the float height. if you accidentally bent on even the slightest when you changed the float needles, it can change the float height. Its a real pain in the arzzz to get them right too. If you have never done it, I would consult professional help.
 
#12 ·
The service manual will have the "float height", and tell you exactly how to adjust. The normal deal is to remove the carb, remove the float bowl. Turn carb upside down, and bend until you meet certain measurements that are in the manual (such as set float height = "bottom of carb body to top of float = 0.74 inch + or - 0.04" this is an example, I don't have the 2000 R6 manual).


When doing a hack job on a MX bike at the track (simple old MX bikes is what my experience is mainly limited to) you would:

- unscrew the cover (or bowl), if turning the gas on causes fuel to flow from the overflow tube (with bowl in place), then the float retainer needs to be bent to press on the needle valve (fuel shut off valve) without needing so much "float". If you can't get it to stop with reasonable bending, then something is wrong with the needle valve, or the float don't float:) (actually another thing to check, they do crack sometimes).

- Once it's not dripping out the overflow, then you can turn the gas on while holding the bowl in place, and see how much you need to lower the bowl to get gas flowing again. If you have to lower it much, then the needle value is too "tight", and you will not get enough fuel height in the bowl. So, loosen (or bend the other way, so the float has to raise higher to cut off fuel) the needle valve retainer.


Also, you have 4 carbs on your R6, right? Is fuel coming out all 4 overflows? If so I'd have to wonder if the fuel pressure switch is not working. Sorry, I have FI R6, so I'm really not much help here:(.
 
#16 ·
OP - I think you've proved float height is the issue.

OK, so I had to find a service manual for your bike. :) You can download a service manual here:
http://www.r6messagenet.com/forums/r6-maintenance-technical/39254-r6-service-maintenance-repair-manual.html

Download both the 1999 Service Manual and the 2000 Supplement.

Look in the 1999 manual (there is only a 2000 supplementary manual that does not mention float height). I assume 1999 and 2000 had same carbs? IDK for sure.

They describe the correct way to set float height on your carb. Seems easy, but they suggest a special tool (Fuel level gauge 90890-01312). See 6-12 in the 1999 service manual. Doesn't look like it would cost much. Basically a bent tube to attach where the drain is now, with a level sight of some sort at the end.

You probably could just use clear fuel hose (rather than the Yamaha tool), they show you where it should be. I think they are saying that it should just be 17.5 - 18.5 mm below the mark on the carb body.
Maybe someone here that has done this can say for sure.

Float adjustment as described in the 1999 Yamaha R6 service manual:

MEASURING AND ADJUSTING THE FUEL
LEVEL
1. Measure: fuel level a
Out of specification  Adjust.
Fuel level (below the mark on
the body) 17.5  18.5 mm
a. Stand the motorcycle on a level surface.
b. Place the motorcycle on a suitable stand to ensure that the motorcycle is standing straight up.
c. Install the fuel level gauge 1 onto the fuel drain pipe 2 .
Fuel level gauge 90890-01312
d. Loosen the fuel drain bolt 3 .
e. Hold the fuel level gauge vertically next to the line 4 on the float chamber.
f. Measure the fuel level a .
Fuel level readings should be equal on both sides of the carburetor assembly.
2. Adjust:
 fuel level
a. Remove the carburetor assembly.
b. Check the needle valve seat and needle
valve.
c. If either is worn, replace them as a set.
d. If both are fine, adjust the float level by slightly
bending the float tang 1 .
e. Install the carburetor assembly.
f. Measure the fuel level again.
g. Repeat steps (a) to (f) until the fuel level is
within specification.:
 
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