How do you adjust carb float level?

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onanysunday

New Member
Apr 21, 2011
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St. Paul
I had my bowl off the other day to check for sediment and the jet size on my Dellorto. The float did not appear to have any way of adjusting it. There's just a straight metal pin connecting it to the carb. I hear people talking about adjusting the float level all the time, but how is this actually done? What do you adjust to raise it up or down?
 

2door

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Sep 15, 2008
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Littleton, Colorado
Very carefully bend the tang that the float pushes against. It is usually brass colored or shiny silver. It is pushed up by the float and in turn pushes up on the needle valve to close off the fuel flow when the bowl is full. Bending it upwards raises the float level. Or in other words allows the fuel level in the bowl to be higher. Bending it down lowers the float so it will shut off the flow sooner, or with less fuel in the bowl.
Just be easy and don't over do it. A slight change in the tang will drastically effect the float level. Good luck.
Tom
 

onanysunday

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Apr 21, 2011
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St. Paul
Ok, I'll keep an eye out for the tang. I'm trying to recall what that looks like..the tang is above the float, right? So I'd have to remove the float pin and float to get at the above tang? I have a fuel restriction problem and have ordered a new fuel valve from sickbike. I will replace that first and see if my fuel is still being restricted. If it is, then I will raise that float level a bit and see if that helps end my occassional WOT top speed bog issue.
 
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2door

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Sep 15, 2008
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Disconnect the fuel line from the carburetor, open the petcock and see if fuel flows. It doesn't need to be a fire hose flow, just a steady stream. If it just drips or doesn't flow at all blow into the fuel line, toward the tank, and check again for flow. There is a small in-tank filter that threads into the inlet of the fuel petcock. It might be plugged or partially plugged with rust or dirt from the tank. This is a common problem if the builder did not clean the inside of the tank prior to filling the first time with fuel.
The kit supplied petcock allows for sufficient fuel under normal conditions. A heavily modified engine might require more fuel at a sustained wide open throttle (WOT) condition but a stock engine will run perfectly well with the amount of fuel provided by the kit petcock. There have been reports of petcocks that were not completely open when the arrows says it is and that can be confirmed by moving the lever slightly while blowing through the petcock, checking for the place where there is the least restriction. Good luck.
Tom
 

onanysunday

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Apr 21, 2011
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St. Paul
Thanks, I'll try that. It's weird because it appears not to trickle at all or maybe only 1 drop per second (when disconnected) but is still enough flow to somehow keep engine going relatively smoothly up until maximum speed. I believe it is gravity feed? and the fuel is not being "sucked in" by a vacuum from the carburetor?
 

2door

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Sep 15, 2008
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Littleton, Colorado
Correct. It is a gravity flow system.
As I said above. If you only get drips, that's not sufficient to supply fuel for WOT conditions. You want a steady stream of fuel from the tank to the carburetor. The float and its needle valve will take care of the rest. Good luck.
Tom
 

adb140275

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Aug 8, 2010
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Harrison City, PA
its a dellorto, tom. you cannot adjust the float level, and there is no need to. upjet and clean out the spray bar (im assuming its an SHA) if there is a bog. shas are rock solid consistent in their stock form when jetted properly
 

2door

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Sep 15, 2008
16,302
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Littleton, Colorado
its a dellorto, tom. you cannot adjust the float level, and there is no need to. upjet and clean out the spray bar (im assuming its an SHA) if there is a bog. shas are rock solid consistent in their stock form when jetted properly
Thanks. Missed that. Sometimes we assume too much. We see so many questions about the same issues that its easy to miss details at times. I'm the first to admit that I'm no Dellorto expert but even so, I've never seen a carb, of any type, that you couldn't adjust the float level on. I'll research, and thanks again.
Tom
 

adb140275

New Member
Aug 8, 2010
176
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Harrison City, PA
yeah dellorto SHAs use 1 piece plastic floats that accept the needle directly. no adjustment, no need for adjustment. i have 3 shas, they are all from the 70s and 80s. they all still work great
 

Goat Herder

Gutter Rider
Apr 28, 2008
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There are a few carbs out there accurately done enough there are no metal tangs or anything just perfectly molded plastic. The few I have seen I was disappointed [no adjustment] but all have worked great so far. My fathers Honda Fat Cat Was one..