The Yamaha manual says to adjust float height with carb body turned upside down, bend middle tab to adjust float height, BUT... make sure the tab doesn't compress the needle valve, only rest on the needle. well, whenever I bend the tab it pushes down on the needle and doesn't change the height of the float. when i put it back together, sometimes gas leaks out the bottom, so I think the tab is pushing the needle open. and the float height isnt correct, but if i bend it anymore, i'll prolly break it.

i think this is a generic question, but if you want to know, it's an '89 Breeze, 125cc. Float height is 21.8-22.8mm.

also, cold running it keeps stalling so i was hoping these adjustments would fix it. once warm, idles perfect and runs good. valves are recently adjusted.

 

When the carb is working, the fuel fills up the bowl which raises the float UNTIL it hits the needle. If you bend the tab up (carb upside down) it will raise the level of fuel in your carb.

When it says not to compress the needle valve they are probably talking about when you are measureing the height.

 

Its not very often the float is out of adjustment. But what works for me, is instead of going the full 180 degrees, and turning it completely upside down, only turn it about 120 degrees, and watch the needle and tang. stop rotating when the needle is lightly pressed, then do the measurement.
Check your idle mixture, you might have to go more rich, sounds like you have a lean condition in the idle circuit, and a low float will cause this , but a too small pilot jet and/ or mixture screw adjustment is usually the cause.
Make sure youre going the right way with the tab...if you have gas leaking out the overflo, the floats are too high, or the needle isnt sitting good in the seat.

 

well, i ordered a new float cuz i think i bungled this up so badly. i think it comes factory set to spec. then I'll check it. but whadda a joke on price: $29 (US). for a plastic float. i gotta get over these stupid prices. that is one good thing about all this Chinese stuff; their parts prices are cheap.

i've set the pilot screw to spec and then tried tweaking 1/2 a turn either way, no difference. also, needle valve assembly was cleaned. if this new float doesn't do it, then maybe i'll replace the needle valve assembly (only $40 US).

hey, would changing the needle height on the throttle body piston change any of this?drop it down or up?