OMG I have to tune a CNS!!! Help

Hey Guys I bought a CNS (boo me later) and it runs great outta the box. I just need help ajusting the float cause fuel is pi**ing all over the ground. If anyone has pictures on how to do this or detailed instuctions I would greatly appriciated.

-Hawaii
 
You just bend it. It's not very technical. The higher the float is, the more fuel it will let in. The lower the float is, the less fuel it will let in.
 
But where is the tang at I don't wanna crack this thing open and mess it up. Do I need to undo the bottem where the bowl is??? Thanx again

-Hawaii
 
So #23 is what I need to find inside and bent ever so slightly to stop the flooding in the vents??? Thanx

-Hawaii
 
We talk about adjusting the float level on page one, post one, of this thread. It's easy enough to do.
 
I tried 2 CNS carbs on a 66cc with no luck. Got a speed carb today and the bike runs frickin' great.

Not going to give up on CNS tho. Once the engine is broken in properly I'll be drilling the jet out and strapping that picky ***** back on there. I honestly think it can be a better carb once it's tuned properly.

One question, what exactly is 4-stroking? And what does it sound/feel like? Cuz one the way up to top speed the sound of the engine changes (of course), just wondering if it's normal-ish.

Thanks for all your guy's help!! This forum saved my ass!....and countless hours.

Wish I had pics cuz my bike looks dope.
 
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Thanks for your quick reply.'
Is this corrected by adjusting the needle clip to run leaner? Even tho my plug is nice and brown?
 
It really depends on what throttle position your carb is at when you experience 4 stroking.
It is a very common mis-understanding that one should tune a carburetor for problems encountered during a particular RPM range. The truth of the matter is carburetors meter fuel in relation to throttle position and the air flowing through them, not engine speed.
The needle controls fuel flow from just off idle to 3/4 throttle.
The fuel jet controls fuel from 3/4 to full throttle.
(There is more to it, but that is just the basics that usually lets one tune these simple carburetors.)
There is overlap in the control circuits so when you adjust one it will have a slight affect on the other.
You need to determine at what position you are having issues at and tune accordingly.

The easiest way is to put a piece of tape on the throttle grip housing and another piece on the throttle grip. With the grip at the idle (closed position) mark a line on the grip tape to act as a reference arrow. Also directly across from this reference arrow put another mark on the housing tape to indicate closed position. Now hold the throttle grip at the full throttle position and put a mark on the housing tape to indicate full throttle position. Now put equally spaced marks in between the marks you made on the housing tape to show 1/4 throttle, 1/2 throttle, and 3/4 throttle. When you ride the bike and the engine acts up you now can glance down at this home made indicator and easily and accurately see where the throttle position is. No guess work or hunches needed.
This makes tuning the carburetor easy as you can tune the exact fuel circuit that needs tuning, not another circuit that you think might be the problem.

When you are done, remove the tape.
 
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biknut said:
The only way removing the vent tube could make any difference is if it was pinched to start with. It's just a vent tube to the float bowl. It really doesn't matter if it's vented to the air cleaner, or the atmosphere. It's not like it's a crankcase vent, or something like that going into the air cleaner.
Click to expand...

Might be a good theory, but not true in practice. Unlike some of the others, when I pull this tube from the air filter my bike runs like crap, I lose 7-10MPH from my speed. Put the tube back in the air filter and it runs good again, top speed is restored... I have repeated this test several times, same result each time....
 
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