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Old 05-19-2013, 07:09 PM   #14491
Gnarly Adventurer
ausibatla's Avatar
Joined: Mar 2009
Location: Waroona, West. Australia
Oddometer: 454
Originally Posted by wundis View Post
i'm confused now :/

it starts fine, works fine for 20 seconds, then starts to work like a hit n miss engine + black smoke out of the exhaust.

i've measured the float level with calipers - the lines are perfectly paralel, the level is at 14,7 mm. float level setup was made by following this link

i thought the k&n filter might be the faulty bit, but no - the stock filter does absolutely the same thing.

now when i measured the float level with the transparent hose the first time (carbs off, fuel in, tidy measurement taken) the results were +-0mm.
Now I checked the fuel level after I shut down the engine - i got surprising results, both floats were way up, like +7 mm up. how is that possible? if I bend the adjustment tab on the carbs to compensate for the +7mm , the lines won't be anywhere near parallel.

i somehow get a feeling that the new replacement needle floats (oem) have weak springs and are not able to hold up the floats in the middle point, vibration does its job and the small springs get pushed in, thus raising the floats and flooding the carbs = ergo the black smoke and shitty run.

guys, i'm stuck and i need advice. buying another set of needle valves is a true robbery. bringing back these - dont think it will work like that.

If you set the float height with the carbies level on the bench then they will be out a bit because they sit on the bike at a slight angle but 7mm is far too much because of that. Before you start pulling things apart again try adjusting the mixture screw. You might get lucky.
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