smellydog wrote:
Was advised to do the "clear tube test" but can't locate the thread about how to do this. Basically, I want to know how to use a clear tube to check the float height on a twin. Any carb tuning advice would be appreciated.
This is a learning step for me, as I will probably mess my carbs up before I send them to wg to rebuild. I just want to know how to tweak them, for future maintenance, without messing them up.
This will be rather generic without knowing for sure which twin, make, model and year, and particular carb fitted. Am guessing KZ750 twin, but don't know if they used the same carb in all years.
To determine fuel level inside the float bowl.
Carbs level as possible, such as bike on centerstand, propped up or held level.
Turn petcock off and drain the bowl.
Connect a clear tube to the drain on the bowl (not the overflow nipple). My recollection is hazy in thinking some carbs (?CV?)may share a nipple for drain and overflow, which nipple I'm guessing could be used. But don't use the overflow nipple when there's a separate drain screw.
With correct size o.d., the plastic tube may be "threaded" into the drain screw hole. Or a plastic connector may be "threaded" into the hole, to which the tube is attached.
Run the tube up vertically beside the bowl. Hold it real still and steady.
Turn petcock on to allow fuel flow into bowl.
Fuel level in tube should match level inside bowl, which on manual slide Mikunis is typically supposed to be 2-4 mm below bottom of carb body (same as 2-4 mm below bowl gasket), but I don't know the specs on CV or other type carbs.
The
test won't mess up anything inside the carb. The "messing up" part comes later when attempting to
adjust the level by bending the float tang.
Good Luck!