Carb controls mystery ?

[jmperry55]

Okay, started my second ever kit installation with a 48cc Grubee Skyhawk I got from KingsMotorBikes (1st was a silverslant 49cc I got from BGF) thinking I could knock off some time and a lot of aggravation since I'd done it before. Wrong! This kit came with a different style carburator that has two control cables already inserted and attached to the carb. One is obviously the throttle but the purpose of the other eludes me. References and pics in the downloadable PDF instructions, none of which actually match the product, suggest it may be a high-performance carb. The control end of the cable is designed to be mounted on handlebar and looks like a thumb push bell ringer. There is no manual choke on the carb, so I'm thinking remote choke? But it is not connected to a chokelike baffle that I can see ( I removed the aircleaner). Fuel shut-off? I don't know what this is, or which screws on the carb are fuel & air adjustment screws. Can anyone help?

 

[oldtimer54]

Its your coke.

 

[rohmell]

Looks like your new kit has the new CNS carb with remote fuel-enrichment thingy.
Read thru the forum here, and you will find many members having problems with that carby, and the simple solution is to buy a normal little NT carb, and the problems are solved.

 

[kojak]

Or, you could try installing it first. You're offering a solution to a problem that doesn't exist yet.

 

[rohmell]

Or, you could try installing it first. You're offering a solution to a problem that doesn't exist yet.

The problems are built into and exist in the carb, whether or not it is installed.
But, give it a whirl and see what happens.

 

[GearNut]

It controls an enrichment device built into the carburetor.
Instead of literally choking down the air supply with a plate covering the intake of the carburetor (the style you referenced to and are familiar with) to enrichen the air/ fuel ratio, this type is like a teeny auxillary carburetor. Sorta like having 2 carburetors in one.
It is opened or closed by a plunger with a rubber seal on the tip. Plunger down is closed. Plunger up is open and it will meter more fuel into the intake charge for starting and warm up. There is a fixed position, non adjustable needle in the center of the plunger, similar to the needle in the center of the main throttle control slide, that alters the fuel flow of the enricning circuit which lets you slowly close off the enrichner as the engine warms up.

 

[oldtimer54]

Looks like your new kit has the new CNS carb with remote fuel-enrichment thingy.
Read thru the forum here, and you will find many members having problems with that carby, and the simple solution is to buy a normal little NT carb, and the problems are solved.

I have the after market ver of that carb and I have never been able to do what I can do now, more power from the bottom to the top of my RPM band.
My bike has a much better bottom end and goes over 40 easy. I love this carb.

 

[dag_29307]

Or, you could try installing it first. You're offering a solution to a problem that doesn't exist yet.

The problem DOES exist!

It just depends on which version you have. If you have the one with the red air cover, The problem lies in the POS!!! CNS V2 carb.

If you were lucky and got the CNS V1 Carb. then give it a whirl I have heard many good things about them.

I have one of the CNS V2 carbs. and have had nothing short of a headache. I just bought a regular NT carb. off BGF on ebay for $12.50 and now I'm rolling again.

This is based solely on my own experiences,

 

[matthurd]

my cns v2 doesn't idle very well at all, but if i tighten both screws all the way in it moves quite nicely, and the remote chooke is very nice, just give it a puss and starting the bike becomes much easier, once the bike is running strong turn it off and you're good to go. mine wasn't bad at all.

got my c clip set to the second notch from the top, and i have a pretty darn perfect plug color if i do say so myself. im basically at sea level for anyone who is interested.

 

[Greg58]

the cns carb has a vent tube that runs from the bowl to the back of the air cleaner, on mine and three of my friends we removed the hose from the air cleaner and the engine runs great. It turns out that the engine is drawing gas from the bowl! Se my post and pic.

 

[jmperry55]

It controls an enrichment device built into the carburetor.
Instead of literally choking down the air supply with a plate covering the intake of the carburetor (the style you referenced to and are familiar with) to enrichen the air/ fuel ratio, this type is like a teeny auxillary carburetor. Sorta like having 2 carburetors in one.
It is opened or closed by a plunger with a rubber seal on the tip. Plunger down is closed. Plunger up is open and it will meter more fuel into the intake charge for starting and warm up. There is a fixed position, non adjustable needle in the center of the plunger, similar to the needle in the center of the main throttle control slide, that alters the fuel flow of the enricning circuit which lets you slowly close off the enrichner as the engine warms up.

Thanks for your extensive and detailed reply, Gearnut, and all the helpful replies. I really appreciate the information and feel confident enough to continue the installation tomorrow. A lot was posted about about the relative merits of this new style carb. I can't determine whether I have the CNS V1 or V2. It is the red air cleaner cover and has the numbers C-32CNS66-EPA on a sticker on the side. I'm going to roll the dice and install it as is, but it's nice to know I can get the old style replacement fairly cheap if needed. Thanks again to everyone who responded.

 

[matthurd]

Thanks for your extensive and detailed reply, Gearnut, and all the helpful replies. I really appreciate the information and feel confident enough to continue the installation tomorrow. A lot was posted about about the relative merits of this new style carb. I can't determine whether I have the CNS V1 or V2. It is the red air cleaner cover and has the numbers C-32CNS66-EPA on a sticker on the side. I'm going to roll the dice and install it as is, but it's nice to know I can get the old style replacement fairly cheap if needed. Thanks again to everyone who responded.

that's the V2, like i said, tighten both screws all the way down initially, and adjust from there, but i found that keeping em both all the way in worked best for me.