Adjusting Float Level

From: Sebastien (Original Message) Sent: 10/6/2008 10:24 PM
Hi, this is a newbie question. I had a sunken float on my K7 this summer so i replaced both floats without changing anything on the new factory replacements. I noticed that the little tab where the float valve sits was a bit higher than the tab on the old floats.

Now my bike runs obviously just a bit too rich: light carbon deposits on the plugs, small pops when slowing down after releasing the throttle, a bit of hesitation on quick throttle open from idle (and even backfires sometimes but rarely)

I would have thought that raising the tab would have pushed the float valve up "sooner" as the gas level increases in the float bowl resulting in lower float level and leaner mixture. Considering how actually my bike runs, i guess this is simply the contrary but i will be glad to read from you on this topic and your expertise is very appreciated.

Thank you all

Sébastien


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Recommend Message 2 of 8 in Discussion
From: Kerry Sent: 10/6/2008 10:59 PM
All floats for these carbs should weigh exactly the same, so a higher tab should shut the float valve sooner. You could clean them up and take them to a compounding chemist - he can weigh them for you. A small cheap balance scale will tell you if they're the same weight, though. If you need directions for setting the float height, just ask.

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Recommend Message 3 of 8 in Discussion
From: Sebastien Sent: 10/7/2008 8:20 AM
Thanks a lot for your input Kerry. I would appreciate hints and directions for setting float level correctly.

Sébastien

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Recommend Message 4 of 8 in Discussion
From: Kerry Sent: 10/7/2008 3:42 PM
To check the float height, make yourself a gauge out of one of those junk credit cards that arrive in the mail every few day. Set the float bowl down on it and mark the edge across the narrow dimension of the bowl. You're going to cut INSIDE these marks so the edge of the card will ultimately rest on the edges of the carb body. Scribe a line exactly 2 cm. below the edge of the card - that'll be the float height. Cut a rectangle out of the card (Xacto knife, single-edge razor blade) within the float bowl marks and along the scribed line, then hold the card up to the bottom of the carb and cut away whatever is necessary to clear the jet tower. Hold this under the carb so the bottom of the float rests on the inside edge of that 2cm box and the edge of the card contacts the bottom edge of the carb body on both sides. Turn the fuel tap on. If fuel leaks out, your float level is too high. If no fuel leaks out, lower the card just enough that it doesn't contact the edges of the carb body. If fuel doesn't start to flow out of the float valve, your float level is too low. Adjustment is made by bending the little tab that contacts the needle. Since at least some of the carbs use a needle with a spring loaded float contact, setting the float level with the carb upside down may not work. This is easier, anyway – and it doesn’t require taking the carbs off.. The motor will get along perfectly well with the level slightly low but it cannot be higher than the 2 cm level.

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Recommend Message 5 of 8 in Discussion
From: Sebastien Sent: 10/7/2008 9:23 PM
Thank you very much for this invaluable information! I'm gonna work it out tomorrow.

Sébastien

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Recommend Message 6 of 8 in Discussion
From: Sebastien Sent: 10/8/2008 11:02 PM
Kerry,
i must thank you again for this great tuning procedure, i am amazed how simple it is and how great the results are. I'm just back home now after a test run and my bike runs perfect! The throttle response is quicker and smooth, the engine runs smoother all along the rpm curve. No more pops, just a so excitingly satisfying roar

My float levels where definitely to high.

Sébastien

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Recommend Message 7 of 8 in Discussion
From: MSN NicknameUnpaintedHuffhines Sent: 10/10/2008 11:29 PM
Yes, yes, yes!!

Many props and much thanks to Kerry. I made myself a float measurement tool out of one of my wife's old credit cards, exactly as described above, and it worked perfectly. I had to adjust the left-hand float tab just a fraction, but it made all the difference in the world. The bike runs perfectly now.

Before today, I absolutely could not get the bike to pull more than 65mph and nothing above 5500rpm. Every time I would try to best that mark, the bike would sputter, shutter,and cough.

Now the bike hauls the mail. 80mph is absolutely no problem. Thank you, thank you, thank you. I did not have to remove the carbs, and this saved me a ton of time and more importanly, frustration!!

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Recommend Message 8 of 8 in Discussion
From: MSN Nicknamedinosaurthatroars Sent: 10/11/2008 8:10 AM
hahahahhahah ya do it yourself and save ..not just on the adjustments but the loss of one card in yer wifes bag is worth what
at several hundreds a yr hahahahahahah paul

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