cns carb. JUNK ?

Discussion in 'Spare Parts, Tools & Product Developement' started by danlandberg, Jul 9, 2011.

  1. danlandberg

    danlandberg Member

    What is up with the "cns" carb ? I bought a GRUBI kit (66cc) because it came with the cns carb! So far, this carb is nothing but JUNK!!:poop: I have a stock (48cc) carb on now and it runs good! (30mph). There is no throtle cable adjustment, and the air adjust screw, and idle screw are "lock tight) solid!!! What is up with that?:confused: I'm going to get a "speed" carb, because I know they work! If Anybody has any input on this, PLEASE respond!:thinking: Need to know the proper jet size and what notch your needle clip is set at? I'm in L.A. (southern calif.) THANKS Dan

  2. Sgt. Howard

    Sgt. Howard Member

    CNS carb

    the locktite issue has to do with CARB laws in Californicatia- did you buy through Kings'? I have similar on my engines that I just bought- also there is an issue with gunkus in the main jet. If you cannot get it to do much more than idle, get to the main jet and pass a pipe cleaner through it's tube and soft wire through the jet. As for the locktite, that's actually epoxy... soak with gas and see what happens. Also, you can adjust the throttle cable marginally where it curves out of the handle but you have to dismount the handle to do it. Should you want more release of the cable, open the handle and shave down the stop of the grip with a good sharp wood chisel.
    the Old Sgt.
  3. PatTheThird

    PatTheThird New Member


    Consider the RT carb from I am soooo happy with it.
  4. thearcticfisherman

    thearcticfisherman New Member

    yo dont knock the CNS carb really! if you had a clue look at what the problem is no really look at how big the carb is and how small the air cleaner is. BAM!!!!!!!!!!!!!!! go buy a air cleaner for a pit bike, you will have to do a mod to make it fit but i tell ya what my bike went from doing 4 stroking and only 20 mph to no 4 stroking and 33 mph!!!!!! hope this helps to everyone!!!!!!!!!!
  5. danlandberg

    danlandberg Member

    I have tried running the CNS carb w/out the air filter, jet is clean, still no good!!! The cable is to long for the housing. So I cut a small push spring ( like whats in a ball point pen ) threaded it over inner cable to take up space and will compress at full throttle so the cable pull won't break, they are plastic twist throttles (cheap). I have had good luck with the SPEED carb, but I'm going to check into the RT carb. I'm in So CA now just above sea level. It should run better than it does. Thanks for the reply!
  6. lazydog

    lazydog Member

  7. Joeeastman

    Joeeastman New Member

    I had this carb with my skyhawk gt-5 and it was ok at first but that was the first engine that i ever had. My experience with these are that in time, the intake port on the housing will probably break, which i have seen happen already on friends bikes and the choke never seems to function properly. I got an NT carb, very simple and have had excellent results and reliability with it and they are cheap...
  8. danlandberg

    danlandberg Member

    The CNS carb came with my GRUBEE gt-5 and it never worked right.! :icon_cry: The air adjustment screw is loc tite(ed) so you can't adjust it, The idel screw is the same way. :veryangry: The piston plunger style choke W/cable SUCKS. :ack2: :poop: It was a good thing I had two stock carbs in my collection. :sweatdrop: I had a flying horse engine W/"SPEED" carb, (stold in Utah):( it ran great!!! :tt1: Going to get another "SPEED" carb and put my SBP chamber back on when I have a little extra $$$, :whistling: (Like there is a such thing as "extra" $$$). I'll stick with the "SPEED" carb any day, inexpencive and simple. :D
  9. VROOM

    VROOM Member

    I too am having trouble with my new CNS carb. It floods, choke doesnt work, stuck needles and runs terrible... I got a cheapo stock carb but it didn't come with a gasket . It also fits on the manifold very snugly. Should there be a gasket in there? Do I need a different manifold?
    I'm only asking you because your running the same engine and the same carb. Thank you.
  10. Al.Fisherman

    Al.Fisherman Active Member

    The seal between the manifold and cylinder can be sealed with RTV. Or cut a gasket out of gasket material sold at many automotive stores.
  11. geebt48cc

    geebt48cc Member

    CNS has been nothing but a paper weight on desk. What's so funny, is I really made sure that the (2010 Skyhawk CNS) was going to come with kit for a major boost in performance.

    REALITY--------------- I had a lot of papers on my desk that were blowing around, and I needed to have something I could put down on top of them to anchor them down. Awwww, CNS can hold down about a foot of paper stationary on my desk all at one time!!!! Thanks CNS from Skyhawk!!! It looks really good just sitting there on top!!~
  12. VROOM

    VROOM Member

    Good to know. But its the lack of room for a gasket between the carb and where it mounts to the pipe coming from the engine that troubles me. The opening on this carb is just so small.
    I guess i will try cutting a washer type gasket go in between. I just need to try not to make aluminum shavings again when sliding the carb in place.
    Last edited: Feb 12, 2012
  13. Sgt. Howard

    Sgt. Howard Member

    CNS carb

    Hmmm.... When I do the building of the next three bikes this Spring, I will render my instructions regarding the CNS carb. I've set up three of them so far, and they do require effort to overcome the "CA SMOG" issues... Kalifornicatia cannot alter a mechanical device without destroying it- you should see the 'recommendations' they impose on firearms manufacturers.
    STEP 1- pull off the air cleaner and PLUG THE BYPASS HOSE WITH A SCREW!!!! That way, externally there is no alteration. STEP 2- Open up the throttle handle and shave off some plastic where the throttle stops. The wretched thing is set up to run super lean- the only way it can do that is to run high idle. If you reduce the stop buffer of the white plastic on the handle, you can reduce the idle. Then it's an issue of RTV gasket sealant to mount the carb- that's it in a nutshell, but images will certainly help :army:
  14. geebt48cc

    geebt48cc Member

    Sounds like you've worked something out?! Appreciate if you have any images of what you've done to get the CNS to work?

  15. lazydog

    lazydog Member

    Attached Files:

    Last edited: Feb 13, 2012
  16. geebt48cc

    geebt48cc Member

    Thanks Lazydog, but I couldn't get site to come up? If anybody has pics just please send them on....................

    Thanks again. I just know that this CNS has the capability of being better than the "Speed" carb I'm using. (HOPE I'M RIGHT???)
  17. SdCruizer

    SdCruizer Member

    I just ordered one from BGF, im sure its a clone of it
    then later found out that offset intake tube doesnt come with it, so I had to scramble around to find one of those

    Hopefully I dont run into any issues but at least I got my stock carb working great I can always throw that back in

    ive been searching a ton about this carb, on another site they had pictures of what all the hoses or nipples do

    for the idle air tighter is what, richer or leaner?
  18. VROOM

    VROOM Member

    Tighter is generaly leaner.
  19. SdCruizer

    SdCruizer Member

    I finally got my cns clone carb working
    The first time I tried it the idle was very high and erratic. Im wondering if then I had some sort of intake leak. But top speed was 4-5 mph slower then my stock carb no matter what adjustments I made to the air screw.
    I had read they all needed to be drilled out larger, but from my little experience it seemed too rich.

    So I had ordered a small set of drill bits and finally got around to trying it again. I noted the stock jet is a 72. After going one size larger and up to 3 sizes smaller I found 70 to work the best. This is drilled jets, not bought ones.
    But the idle was always perfect, so im not sure why this time there were no problems I even used the same intake (stock) some reason the offset would still allow it to hit my frame. Didnt use the offset originally either.

    Now my acceleration from a dead stop is smoother, better and I gained 2mph top speed on my short top speed run I do with my gps. I have not done an official all out top speed run yet.

    So I would suggest anyone who buys one, either buy the jets from sickbikeparts or a small set of drill bits and be prepared to rejet it both directions.
    It really doesnt take that much time to do it, the carb is so easy to take in and out.
    I also had to adjust the needle for mid range smoothness too once I got the main figured out
  20. motorpsycho

    motorpsycho Active Member

    I had a cns carb and i only ran it on my bike for a few days.
    It was a pile of **** in my opinion!
    yes, i know how to tune carbs and this cns would not respond to any tuning that i did.
    this included re-jetting, air-fuel mixture tuning, jet needle settings...everything.
    The carb made my bike slower by about 5 mph as compaired to the stock nt carb.
    not only that, but it would not stay tight to the intake tube.
    my good old stock (re-jetted, tuned, high flow air filter) nt carb gets my bike up to 32 mph, without any 4 stroking, and it will sit and idle all day long.
    with the cns, i was lucky to get 25 mph out of it and it idled like ****.