Modder here!This fourm!This going to help my build alot

The one in the picture is the speed carb "welbro" style.Its not on my bike Fabian..
I just posted it to see if that is the best route to go carb wise.

I bought a locked up bike for 20 bucks today so Iv got spare partsss
 
So is this about the best way to go? Besides also having a reed intake from JNMotors
You were saying the stock carburetor is suck a pain to adjust is this one the best route?
I'm sure I can find it on the forum somewhere,but why not be a real nOOb if im going to be one:devilish:
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That is a CNS 3 (I think) carb, they shipped with 2010 Skyhawk motors, the left set screw is for idle air mix and a pain to get adjusted as which fuel circuits overlap is hard to get right.
The 2011 and later CNS carbs have that fixed and darn good carbs on the long Z-intake and even with the short ones if that filter will fit between your motor and seat post.

You will never get the power from an NT, even a Speed on a 66cc, the opening is just to small to allow the air flow.

Reed kits, boost bottles, ignition kits bla bla bla...
If you have lots of money, time and like to tinker they are for you.

If you just want the quickest, cheapest, and easiest power boost bang for the buck a SBP X-chamber and Iridium plug for under $100 combined delivered is the starting point, if that isn't enough for you or you just want to play, open your wallet and set the time aside is my advice.
 
You will never get the power from an NT, even a Speed on a 66cc, the opening is just to small to allow the air flow.

That's the worst advise i've ever heard; it's completely incorrect. Correctly jetted, and free of air leaks and maladjusted float height, any carburettor will be effective in mixing fuel with air.
 
I've tried most of the available carburettors on the market and non of them gave any extra power over the standard NT carburettor; in fact i went back to the NT carburettor, until Rock Solid Engines brought out their reed valve compatible diaphragm carburettor kit.
This was a big leap forward as it offered an externally adjustable air/fuel ratio method. Even so, the Walbro style carburettor did not make any more power over any of the other carburettors.

If you were to look at things from a point of restriction (on the intake side) the intake tube cross section will govern the maximum amount of air that potentially can enter the engine.
 
That carb looks to seal better and air flow mixture would be awesome RPM,If you have a expansion chamber.+vacum time advance?
I'm pointing at it..It says NH but I think its just called NT.Simple but if it gets too out of wacky then your bike might not run..
 
Far from expert on all things carburetor-ish, I did just get through another round of messing with a Dellorto SHA clone. I fixed the sticky slide. I got the throttle cable length just right. I fixed the sticky choke. I got the main jet just right, which I tested by setting the idle to full blast with no choke on a hot engine at WOT. It ran fine. Had a good sound.

Problem was that anything less than 3/4 throttle flooded the engine, and there was no way to adjust it. I went back to the NT. People say, "Cheap, China, crapola," but the NT units are perfectly decent little carbs that work just fine for these engines. I have noticed that some of the four stroke gurus like using them on the Honda and Honda clones. I'd sure like to test a diaphragm type, Walbro carb, though. That Fabian, as argumentative a cuss as he may be :giggle:, knows a thing or two, and his knowledge has been hard won in real world tests.
 
Roughrider that is a weird way you have of determining the correct main jet size. It's no wonder you screwed up the way it ran at 3/4 and below. The correct way is to start with a small main jet, clock your top speed on a flat road, and then try the next size up. The best jet is the one just after the one that gave you the best speed. But if you have a restrictive air filter then that also screws everything up. Run it with and without the filter. If there's much difference then the filter is too restrictive and it needs to go in the trash.
 
Roughrider that is a weird way you have of determining the correct main jet size.

True that! It was only by accident that I got the fracking thing to even start. In frustration, I screwed the idle all the way in to raise the slide, and only then would it even start at all! Seriously. Having the filter on or off made no noticeable difference. That was how I found out how it ran when bypassing the idle circuit. This was after time after time with a totally flooded engine.

I am thinking now I may have a defective carb. It is SO bad, that I'm just sick to death of playing with it. Really, Jag, if you were here, you'd go, "Hmm. This thing is way, WAY too rich at under 3/4 throttle." So just trust me on that. I'm not a complete idiot.

I'm no guru, but I know the difference between rich and lean. It's not that difficult to determine. I can hear it. I can smell it. I can feel it.

But when you say, "The best jet is the one just after [italics added.] the one that gave you the best speed," do you mean leaner or richer? I don't go by the numbers; I take my bits and measure the orifice. I notice that different manufacturers use different number systems. Example. In the JNMotor jet kit I got, .89 is a smaller hole than .70. So I just measure. Up? Down? These terms are meaningless. Only actual measurements in mm or inches speak to me.

And just so you know, the carb came with a jet that measured 0.280" and my tests showed a 0.0135" jet made it run OK at WOT. That's how far off the carb was when I started.
 
something is definitely off. Is the float height set right and is it shutting off gas? (check with bowl off and move the floats up and down to see if fuel flow turns on and off). There's a pictorial on my site showing how to set the float height.

UP in jet size is bigger diameter.
 
something is definitely off. Is the float height set right and is it shutting off gas? (check with bowl off and move the floats up and down to see if fuel flow turns on and off). There's a pictorial on my site showing how to set the float height.

UP in jet size is bigger diameter.

That would do it. The symptom is catastrophic flooding. I'll check that tomorrow. And thanks!
 
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