78 ke175 float height? - Motorcycles

indicates either low fuel flow or problem ignition
replace the coil with a known good unit --if points ignition , replace the points and set to correct point gap
for fuel , check fuel flow to carby---set float level to correct height
clean /replace air cleaner

Try your local library. They have free access to most service manuals.

Hiya, two possibilities here firstly that your needle valve in the float chamber is stuck or leaking or your float height is set wrongly.

float heights are not usually needed to be adjusted, the float valve will have a rubber tip, so it wont wear and change the float height. if flooding is a problem, new float valves may be necessary, but more likely the fuel tap needs a kit

Float height should not be overly critical.. Why was the float level changed just to rejet? gas overflowing sounds like a stuck Float.

if you are sure that everything is clean, the float height is correct and there is no leak in the float...the problem will be that the float valve tip will have hardened with age and no longer seals correctly. Replace the valve...

Sticking floats or worn float valve needles or incorrect float height, tap float bowls to see it overflow stops (sticky float), remove and clean float bowls and fuel inlet passage with carb cleaner and compressed air, check float valve for wear to the rubber tip. Reset float height by slightly bending the metal tab on the float to adjust the closing height of the valve measure from the carb bowl mating surface to the top of the float when fitted then re adjust 1mm at a time higher untill fuel doesnt over flow.

you put it on the float base and allow the float to drop down and read the gauge where the float is read the top of the oppiste side where the float is hinged.

Alas I could only find a link to a manual for $10...
May be worth it tho if you plan to kep the bike for a long time??

http://www.tradebit.com/tagworld.php/yamaha+xs+400+seca+workshop+repair+service+manual+download