Float height already high, yet U bend method shows rich??

[jonathanhly]

So I am attempting to set my float height. Using the U- bend method, both carbs have too much fuel, about 1/4'' above the gasket level.

Now when I opened them up, the float height was already high. Meaning 14+mm (should be less fuel?).

I measured like this. Setting the carbs in a vertical position, one carb resting on my leg and the other in the air, then leaning the carbs in order to have the float rest on the needle. The needle is fully seated in the opening, and the tang is just touching the plunger. From this position I can push on the floats, which pushes the plunger and then when I release it returns to just resting on the plunger. I then try my best to measure from the edge of the gasket surface to the top of the float.

Is that the correct way to do it? Or do I measure from when the tang just begins to push the needle into the opening (not yet depressing the plunger)?

And if that is the right way to measure, why am I showing too much fuel with the U-bend method, if my float height is already high?

Thank much,
Jon

Does that sound correct?

[jonathanhly]

I guess what I am asking is should I set the float high to the 13mm as required for my carb (which proves to be about 1/4'' above the gasket using U-bend method), or should I set it to about 14 or 15mm which is my estimate as to where the U-bend method will show fuel equal to gasket level?

[jacob92icu]

Wish I could help you, butttt... 
I would need to know a little more about your problem. What type of problems is your current float height causing? Based off just basic knowledge I would say just make sure your float moves freely and does its job by cutting off fuel flow when the bowl is too full.

[jonathanhly]

I have a 2001 gs500k. 6400 miles on it. Everything stock. I adjusted valves and cleaned the carbs.

Now she idles much better than before. Right around 1300 rpm, however applying any throttle whatsoever cases long hesitation followed by heaving bogging.

I think I am running rich. I am fowling the plug in my right cylinder and after a quick idle the right cylinder is far cooler than the left.

I checked the floats as described and they are high. After adjusting and experimenting with may different amounts of adjustment, I finally set it to 13mm like the book says. Tested again with the U-bend method and they are still about 1/4'' high.

Also I tried vastly increasing the float height (to decrease the fuel level), which when I set up to test actually overfilled the bowls and began to drain. IDK why!?

I still have the caps on my mixture settings, so they are still stock.

[twinrat]

you measure from the top of the float to the metal body where the gasket would normaly sit.[eg  with no gasket ]the float is let to find its own level with out  any compressing of any part of the float valve  [[eg  free floating ]]..
I SUSPECT YOU HAVE BEEN MEASURING TO THE GASKET, AND IF NOT THIS ,,I SUSPECT THE FLOAT VALVE'S NEED REPLACING  AS THE NITRILE RUBBER ON THE VALVE SEAT HAS CRACK'S IN THEM FROM AGE
there is also a o ring under float valve also this may have crack's in it to.Use a magnifying glass  if you have to
if the valve rubber looks ok  SUSPECT the o ring
.

[jacob92icu]

Make sure you check all fuel hose connections and check for vacuum leaks. Could be you have your fuel house routing on incorrectly. A good reference for that can be found by doing a google search for fuel house routing on gs500. If you need the link i can get it for you tomorrow.

[mustangGT90210]

Do check fuel hoses. My bike didn't like to run or work really well when I got it because the hoses were routed wrong. Like in the wrong places and through the wrong nipples on the petcock...

Don't think "Oh they have to be right, whatever." That's what I did... I finally listened and it fixed so much 

[Paulcet]

In my experience, setting 13mm (or whatever) was no help.  I even milled a little piece to help measure, and got it quite accurate.  However, it did NOT correlate to actual fuel level.  One bowl was a little high, the other was very high. 

So now I use the U-tube, never removing carbs from the bike.  Then remove bowl (after shutting off the petcock and drain the bowl) tweak the tang and then reassemble and recheck.  After doing this a couple of times you get a feel for how much you have to move the tang to make 1mm of change.  Socket head cap screws on the float bowls are greatly helpful!

[jonathanhly]

Paulcet, I think I am going to just dismiss the 13mm float height and just set it to correct U-bend height. Just to make damn sure, if I have too much fuel, i.e. above the gasket line, than I bend the tang up (towards the needle)?

[Paulcet]

Correct!