Need link to procedure to set float height BS34

I am tired of searching. How do I set the float height properly? I keep seeing clear hose referred to? Is there a link to a write up? Thanks1

I don't know where you would find a "write up", but the procedure is fairly simple, and I'll try to explain it for you. Take a length of 3/16" clear vinyl tubing about 12-16" long. If you like, you can take a fine tip Sharpie pen and mark two lines 3mm apart a couple inches from one end.

Put your bike on the center stand so that it is as level as possible.

Move your petcock to the "PRI" postion (if you have a vacuum petcock). Otherwise, turn it to "ON" if you have a manual petcock.

Attach the non-marked end of the hose to the drain nipple of a float bowl. Hold the marked end of the tube up against the side of the carb body, with the top mark even with the line where the bottom of the carb body and top of the float bowl meet.

With a screwdriver, open the drain screw at the bottom of the float bowl. This will allow gas to drain from the bowl and fill the tube up to the lower mark on the tube. If an air bubble gets trapped in the tube, flick it with your finger until the bubble clears--otherwise you will not get an accurate reading.

Have a gas can handy so that after taking the reading, you can close the drain screw and drain the gas into the can.

Repeat for each carb.

If the gas level is not within 1mm of the lower mark, then you need to adjust your float level. Switch your petcock back to the off position, then drain your float bowls. Remove the carbs from the bike, and remove the bowls of the carbs that need adustment. Remove the float assembly and carefully pry the adustment tang up or down, depending on if you need to raise or lower the level. Make SMALL adjustments. It doesn't take much movement to make a difference.

Reassemble and retest. Repeat until levels are in spec.

Skyman, Thank you very much for taking the time to explain it for me. What a great forum.
Will Piatt

del

The tang is the small metal square that contact the spring loaded pin in the float needle. Curious about how you flex a tang. I suspect that if the float level changed after you flexed it, you actually bent the thing. I would never recommend bending anything else on a float as it only mis-orients them making further adjustment even harder.

del

Here is a pic from kz400.com that shows the device to check the fuel level.

Great info guys. Can this adjustment be done and tested on a work bench or does it have to be done on the Bike?

Stevec6535 wrote:

Great info guys. Can this adjustment be done and tested on a work bench or does it have to be done on the Bike?

It can be done on a work bench. You just need to make sure the carbs are mounted to something stable (I use a bench vise with a towel to protect from scratching), and that they are level front to back and side to side. You then need to have a free-flowing fuel source situated somewhere higher than the carbs so that gravity can feed fuel into the carbs.

I don't think it would be easy to do the procedure with the carbs on the bike. While they are fairly level, they are not exactly level. We put the carburetors in a carburetor holder and use a level to ensure the carbs are perfectly level.

If you put the carbs in a vise, and it is just fine to do so, I would be a little scared to use a towel. The towel will help protect the surface a bit from scratching but vise pads allow the pressure to be distributed. I have bent the intake venturi on carburetors in the past and never realized what caused it. That stopped when I started using vise pads. I have several sets I bought from Golfsmith, a golf clubmaking supply place and a couple other sets that are L shaped and hang over the jaws of the vise and have rubber pads. Both work well. I don't remember where I got the metal (with rubber) pads but it was probably a home improvement place or hardware.