Fuel FLoat

[Byte]

Here is what i read off soem other forum...

"As the fuel enters the float bowl, it causes the floats to rise which push against the fuel inlet needle.

Once there is enough fuel in the float bowl to raise the floats to the specified "float level", the fuel inlet needle makes a seal with the fuel inlet valve seat cutting off the fuel supply.

As the carb uses fuel and reduces the amount in the float bowl, the floats are lowered and the seal is broken - allowing more fuel into the float bowl until the desired level is reached and the needle contacts the seat and shuts off the fuel supply."

WHen people talk about altering the tang on top of their fuel valve, how does this bend in tang affect above description?

Byte

[ktmfred300]

It affects the fuel level in the float bowl which can lean out the mixture slightly plus it keeps the fuel in the bowl and not on the ground.

[Gary jp4]

Usually the subject comes up because the float (or fuel) level is to high so we are bending the tab up to lower the level.

However, remember it goes both ways depending on which way you bend it.

You set the float level this way up or down.

[llamaface]

WHen people talk about altering the tang on top of their fuel valve, how does this bend in tang affect above description?

the tang is what transfers the force from the float to the valve, so bending it slightly one way or the other causes the valve to shut at a higher or lower fuel level.

[Byte]

thanks.

So. what impact will:

bending tang down?

bending tang up?

Byte

[odonnks]

[OrbaBill]

The stock setting lets the fuel level be too high, and this results in a lot of gas sloshing out the overflow and reducing fuel range significantly. Not a problem for track races and short races, but a problem for rides over 40-50 miles

[Mike in Fresno]

depends upon which way you are holding the carb in your hand as to "up or down". With carb apart and held upright, bending the tab UP will cause a lower float level-cutting the gas flow off sooner-and is generally what you want. The work manual photo shows the carb in a more of an upside down view or sideways view.

Just bend the tab a little, no need to measure, people make WAYY to big a deal of this, just lower the float level a little and reassemble the carb. Once back on the bike you dont want the fuel to run out of the overflow hose til the bike is leaned over about 45*. If it runs out later maybe its too low, if it runs out when the bike is on the kickstand its too high.

[rekless]

Hey Mike, I fiddled with the float level yesterday on the 200 and I think I got it dialed. Garett rode it down the street yesterday and he got off with a grin on his face a mile wide !! I caught him out in the garage last fondling and taking pictures of it when he was supposed to be in bed !!! ha ha !! I guess there are worse things that he could be out late doing huh ?? Thanks again, Chuck

[EXxrldtgnow300dtg]

Hey Mike, I fiddled with the float level yesterday on the 200 and I think I got it dialed. Garett rode it down the street yesterday and he got off with a grin on his face a mile wide !! I caught him out in the garage last fondling and taking pictures of it when he was supposed to be in bed !!! ha ha !! I guess there are worse things that he could be out late doing huh ?? Thanks again, Chuck

Cripe, I'm 41 and I still find myself looking over at my 09 300 everytime I'm in the same space. Now if I woke up in the morning, naked, laying next to it, I'd know I have a problem. The orange, black and white KTM's are damn sexy bikes. The two strokes are the sexiest dirt bikes around. They even have that hourglass shape to them and just love to be ridden hard and dirty.?

[Mike in Fresno]

Cool Chuck, did I leave it too high or was it a piece of dirt in there??

[rekless]

Probably just a hair high still....but Im not sure. I pulled the carb and douched it out with some gumout and that might have been what did. I lowered it ever so slightly and just followed the rec's in the manual. Were good now though !!!

[Byte]

depends upon which way you are holding the carb in your hand as to "up or down". With carb apart and held upright, bending the tab UP will cause a lower float level-cutting the gas flow off sooner-and is generally what you want. The work manual photo shows the carb in a more of an upside down view or sideways view.

Just bend the tab a little, no need to measure, people make WAYY to big a deal of this, just lower the float level a little and reassemble the carb. Once back on the bike you dont want the fuel to run out of the overflow hose til the bike is leaned over about 45*. If it runs out later maybe its too low, if it runs out when the bike is on the kickstand its too high.

Thanks Mike.

So, just to clarify things - when u say "upright" - do u mean just like it sits when installed into bike?

My bike runs differently now that I have fiddled with the float level. It does not hold idle and smokes more - I am trying to overcome these issues.

Byte

[trailmeisterjoe]

YES, as it is mounted you bend the tang UP to lower the level.

Joe

[EXxrldtgnow300dtg]

Is it safe to say that if fuel doesn't come out until you get to a 45* lean on the bike that the float is where it should be?

[Byte]

Once back on the bike you dont want the fuel to run out of the overflow hose til the bike is leaned over about 45*. If it runs out later maybe its too low, if it runs out when the bike is on the kickstand its too high.

OK - I spent 5 hours on this today and I think I have succeeded in obtaining the correct float height.

I ended up not worrying about measuring the height - instead trial and error of removing and re-installing carb/float 12 times to obtain that sweet spot of the tang where fuel does not piss out of the carb @ 90 degrees but seeps out at 45 degrees.

Many thanks for the heads up Mike and others!

Byte

[Byte]

Once back on the bike you dont want the fuel to run out of the overflow hose til the bike is leaned over about 45*. If it runs out later maybe its too low, if it runs out when the bike is on the kickstand its too high.

OK - I spent 5 hours on this today and I think I have succeeded in obtaining the correct float height. ?

I ended up not worrying about measuring the height - instead trial and error of removing and re-installing carb/float 12 times to obtain that sweet spot of the tang where fuel does not piss out of the carb @ 90 degrees but seeps out at 45 degrees.

Many thanks for the heads up Mike and others!

Byte

[Mike in Fresno]

glad you got it worked out, you will also see better fuel mileage too, and when up high in elev the jetting will work longer before the bike gets too rich.

[Byte]

thanks Mike.

Just what is an acceptable amount of smoke coming out of exhaust?

I am now fine tuning with air screw and mixture screw and see this varies quite a bit.

Byte

[Mike in Fresno]

there is no "mixture" screw, only the idle and air screws. The more oil in your mix the more smoke, the more total fuel the more smoke, the brand of oil also makes a difference. Generally with a synth oil, once the bike is warmed up after riding for a bit, you should see almost no smoke at all. While riding no smoke, when on the stand and you rev it you will see a little. If the bike gets real hot, from like a hill climb, then it tends to smoke a little from the pipe getting hotter and burning off some of the oil in it.