Author Topic: Effects of Float height?  (Read 4080 times)

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Offline Uzi9mm

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Effects of Float height?
« on: July 12, 2008, 11:10:25 AM »
Anyone know how the float height will effect how the bike runs?   Will the float level have an effect on how the bike idles?
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Offline BDI

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Re: Effects of Float height?
« Reply #1 on: July 12, 2008, 11:30:50 AM »
The float height will cause it to be lean or fat across the board.The best thing you could do is set it correctly and leave it. Trust me playing with float height will cause you more headaches then anything. There are already enough variables to worry about with jetting with out throwing float height in the mix.
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Offline GDubb

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Re: Effects of Float height?
« Reply #2 on: July 12, 2008, 12:20:25 PM »
My float was out of adjustment when I bought my bike and when I pulled in the clutch the motor would race and I would have to feather the clutch to bring the rpms back down. I fixed it ASAP cause I could see the potential for disaster.


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Offline Hillclimb#42

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Re: Effects of Float height?
« Reply #3 on: July 13, 2008, 11:41:12 AM »
My float height was wrong on the 250, when I bought it. It was set so that it hardly stopped the flow at all. It was new to me, so i had no idea about what it was doing to  performance. I did have a cold-foul deal, that i could bet on. Almost every start-up resulted in an eventual fouled plug, after trying to use the throttle just right trying to get warm. Too much gas=fouled. Not enough = fouled. Then with a new plug, started right up and rode the rest of the day. Finally let my buddy work on it and, he found the float adjustment to be way off. Bent the little tabs so that it shut off the valve right, and bammo, now I change plugs when I feel its been so long I can't remember when I put it in there. As for performance, I am not sure, I think it died on me less once fixed. Not sure though if that was the issue because I was throwing the book at it.(pipes, silencers and gearing) I think though, Bdi is right on with the set the float the way it supposed to be set, and tune with jetting. Actually the needle adjustment is pretty big factor to tweek on, but that is another topic altoghter.

Offline Uzi9mm

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Re: Effects of Float height?
« Reply #4 on: July 14, 2008, 08:08:21 AM »
Thanks for the replies.  Just put on a Pro Circuit 2 pipe and 304 silencer.  Cleaned the carb with carb cleaner and checkt the floats.  When measuring from the mating surface for the bowl to the top of the floats (i guess its actually the bottom of the floats) with the carb upside down at an angle so as not to compress the spring pin on the float valve, its 16mm.  Does that sound right?  Am I doing it correctly.  Anyhow, my 5 Hundo doesn't want to idle.  I got the screw all the way in.  It idles for a couple seconds and dies.  Could a backfire damage the reeds?  Carb is set at 2 turns out, 3rd clip, 55 pilot, and 168 main.  I'm at about 5-600ft 95-100deg.  BR8ES at .024.
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Offline Hillclimb#42

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Re: Effects of Float height?
« Reply #5 on: July 14, 2008, 02:59:57 PM »
I didn't set mine, but saw it done. It was set so that when the floats were level, the pin was closed. Not sure about the mm to anywhere spec. I also jus got a PC 2 put on. I also will need a tweek on jetting. I had the Pc platinum, then after some dings put on a stock pipe and seemed to run well. Now with Pc2 it seems a little lean on needle to main. Just had a test little warm-up though so not sure about fattening up just yet, but seems likely.

Offline KXcam22

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Re: Effects of Float height?
« Reply #6 on: July 15, 2008, 03:27:45 AM »
Uzi,
    I recall the spec is 16 to 18mm (not 100% sure) but for an easy method to set it look in the jetting thread. Cam.

Offline Uzi9mm

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Re: Effects of Float height?
« Reply #7 on: July 15, 2008, 04:21:29 AM »
Cam, found your post on how to set the floats.  I'll give it a shot.  Hillclimb, what are your carb settings and conditions?  Are you running a V-force or a Boyesen reed cage?
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Offline Hillclimb#42

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Re: Effects of Float height?
« Reply #8 on: July 15, 2008, 09:47:55 AM »
Boysen, but would like a V-force. 168 main,58 pilot, stock clip position, (3rd, i think). I just put on the PC2 pipe. Looks sweet /sounds lean. Probably will change to 170 main. Conditions vary from Dry and dusty hard pack to super wet and muddy. 70-90 degrees. Not much above seal level here in midwest. Has always run real strong after warm-up, but sound and acts fat while cold. Thats when to jet, by the way, after warming it up. Like I said mine sounds rich coming off the bottom until completely clean. Then its almost lean on needle setting so the hit is smooth throghout power, not a slam at midrange. Its all in the plug reading, man. A good tip that most people don't use (including myself too often) run the bike wide open in whatever gear you want,hit the kill switch while still nailing it. Then you get a true main jet reading. Back me up on this guys, if I am right. Seems crazy, but heard about that method and read it in the manual not long ago.
  Start with stock jetting, if you're bike is stock. Error on the side of a little rich, if you have some mods. The jetting chart really helped mine out. Runs better than just about any stock k5 that I have been around. Can't wait to dial in the new Pipe...... :-D... checked it out at PC and its just a needle change.
« Last Edit: July 15, 2008, 02:33:45 PM by Hillclimb#42 »