Carb Float Tool & Float Level Question

In process of rebuilding carbs on KZ650 SR and purchased this tool. Has anyone used this tool, good, bad. Looking for some feedback.

From the instructions I have read, you place the legs on the carb-bowl interface surface (carb-side). You then tilt the carbs on a angle, so the float closes, but you don't want it to compress the float - hence, you don't place them upside down.

You then lower the measuring leg down to the floats and adjust accordingly.

I have not been able to find the measurement you need to attain when setting the float height. Using this tool, anyone know the measurement?

The float level measurement is fairly inaccurate on older carburetors where the original orientation of the floats has been messed up by folks in the past who have bent the floats and not the tang on the float to adjust them.

Since you don't have your bike year/model in your signature, I am not sure what type carburetors are being discussed but most VM series carburetors spec the float level at between 22mm and 26mm. To use the tool, remove the bowl gasket and turn the carburetors upside down with the bowls removed. The large leg with the measurement gradients and the other large leg that moves sideways go on the gasket mating surface and you slide the moving leg towards the leg with markings until you can get the L shaped piece that is next to the markings above the float. You then lower it until it just barely touches the float and take a measurement. You may need to bend the tang of the float up or down to get the specific measurement needed. If the floats themselves have been bent in the past 30 years, it is more or less a waste of time.

Some types of assemblies like the BS32/34 used on later carburetors call for a 18mm float height and this float height WILL NOT give you the proper amount of gas in the bowl which is about 4mm (most models) below the gasket mating line if you use the service fuel level method of measuring.

Suggest you edit your profile and make a signature with a minimum, your bike year/model and your location if you ever need local help. wg

I ended up using the advice given on the forum, I put the bike up on the center stand and put a piece of clear tubing into the drain hole. Then turned on the gas and held the tubing up to see where abouts it lined up. Then turned off the gas, drained and dropped the bowl and adjusted and repeated.

Took about 30 min to do all 4 carbs and worked well.

Yeah, as I understand the "static set" is just to get it in the ballpark and you will have to end up using the clear tube to get it correct anyway.

If you make yourself a dedicated shorty screwdriver that can remove the bowl screws with the carbs in place, you can drop the bowls really fast and it doesn't take too long to dial it in.

Appreciate the help. To clarify, the bike I am working on is a 79 KZ650 SR (D2). As far as making the clear plastic gauge, you just shove a piece of silicon tube into the bowl drain (make it into a "U" shape and hold next to the carb bowl. Fuel should be about 1/8" inch under the bottom of carb. Kind of just like using a garden hose to find where level across a distace. Is there any other trick to making the clear gauge?

It is a 1979 KZ650 SR (D2). I'll add my bikes to the signature - good point, thanks.

Nope, thats it. It took a bit to get the tube in, but it works. Now I don't have a carb overflowing or the lean conditions I did before.

I think it is better to find a 1/4" straight vacuum fitting and use some teflon tape on the end. Screw it into the hole where the drain screw goes. Put the hose on the fitting. These fittings are available in any autoparts store. You will get a lot less leaking.

Once you have the hose in place and turn the gas on, don't move the hose up or down as you will get a false reading and you will get air in the hose up near the bowl. You can blow gently into the hose or tap it to dislodge air bubbles. The carburetors must be dead level for this method to be accurate so we always do this step on a workbench with a carb holding jig.

I used the mechanical gauge this eveing and set all floats at 24 MM. Based on comments from wiredgeorge, this may be a good static setting.

If I read this correctly, the higher the number of MM's or greater the float height (as measured with this gauges), the less fuel will be in each bowl. At 24 MM, it would shut the fuel off 4MM less than if set at 18MM?

I checked the carbs before I adjusted them, and they ranged between 18-20 MM.

Anyhow, tomorrow will apply the clear plastic hose and verify the levels. Carbs are out, so should be able to level and do fairly quickly.

I found some soft silicone rubber fuel line that happened to "snug fit" into the drain screw hole on mine without leaking, then found some clear tubing with the correct inside diameter that I could shove the end of the silicone fuel line into with a snug fit. That setup makes it really easy.

A time-saving tip during tang adjustment is to temporarily use only one screw to attach the float bowl, which is perfectly sufficient for the clear tube test, regardless of any slight seepage past the gasket.

Credit and thanks to wiredgeorge.

Good Luck!

Thanks for all the help, 1 screw in the bowl trick worked well. Made the clear tube gauge for $1.50, worked great. Did with carbs out. Made a small fixture to level then did one at a time. After manually setting all the bowls at 24 MM, 2 were dead on, the other two just needed a slight adjustment, just slightly high on the fuel level.

Here is a picture of the gauge. On the barb, just forced into the bowl screw hole and threaded it that way, worked just like a die.