So after i last stripped the carbs on my race bike one or more of my float valves started leaking fuel into the cylinders quite badly when at rest. I replaced all 4 float valves and seats with brand new ones from david silver (copies, not genuine honda) and i thought it was ok but when i came down the in garage this morning i could smell petrol and sure enough when i tried to turn it over quickly with the kill switch off there was some hydraulic lock.

Unfortunately the fuel tap doesn't close all that well when in the off position and has a mod to remove the diphram and spring so the only way to shut it off properly is to disconnect a dry break connector in the fuel line, which means removing the seat each time.

I'll be stripping them down again this evening to see which is leaking and if theres any obvious reason but my question is, does anyone know any tips or tricks to help the float valves seal properly?

I know someone one suggested to me that i score a groove where it seats but i'm not too sure about that. I checked when i replaced the valves and seats and the float heights are all set correctly, though i had to adjust one.

I would re-install the vacuum diaphragm in tap

mine kept flooding due to a leaky seal in off position until I rebuilt my tap

It's been fine for the last 18 months until i had to strip the carbs for a running issue.

I'd rather find a way to get the float valves to seal properly than introduce another point of possible failure in the fuel system and restrict the flow with the diaphram.

GeeTee wrote:I would re-install the vacuum diaphragm in tap

mine kept flooding due to a leaky seal in off position until I rebuilt my tap

i wouldnt rely on a vaccum tap to make up for leaky carbs! they shouldnt leak even without vaccum tap (many bikes dont run vaccum taps... its just a Honda safety feature, but it should be that, safety not primary)

if the floats are leaking then the mixture could become too rich when its running, and if your vaccum tap fails and you leave it on then it will flood out anyway...

All I know is I rebuilt the tap with one of rick's kits and (touch wood) it's been fine since

I always leave tap in off position when it's stored in garage