CNS carb working great....

i have the V2 and V3 the V2 is a fine carb if you have the time to tune it but the V3 is the EPA problem child its a junker and the one everyone says to throw out i puled the plug out of mine and it didnt help much all the useless hoses sticking out of it pull in dirt while you ride and put it in the bowl and make it clog up

EPA parts shouldnt be built in china they have no idea how to set them up or do they care if it works right
 
V3 is the EPA problem child its a junker and the one everyone says to throw out

People been saying "throw away your CNS" long before V3 came out, that's for sure. V3's been around less than a year I would guesstimate, haven't had my hands on a V3 to comment on it directly, however, it does come with a better air filter than V2 (the red plastic V2 filter clogs too easy). V2 has the overflow hose coming up from the bottom (that is left open), the vent hose that comes out between the idle screw and air bleed screws, it goes behind the air filter but many people say theirs runs better pulled loose and run open (like V3), it doesn't have the third hose so I can't comment. Seems an easy fix for dirt sucking would be to rubber band some kind of mesh over the ends of the open tubes?
 
yea but its easier to just get a kit without the V3 or to replace it than to screw with it pulling the brass plug and trying to find ways to make it work right its a EPA carb made in china that screws you from the start
 
The biggest hindrance on any version CNS carb seems to be the needle on V3 only has one slot apparently. I have yet to confirm if a needle from V1 or V2 that has 5 slots will work in V3 or not? Has anyone with CNS V3 carb tried that???

My CNS carbs have five slots on the needles- first I've heard of this. In the absence of a lathe, blocking a drill into a padded vice will allow slots to be cut with a fine-toothed hacksaw blade. Practice on brass rod stock before you attempt such a thing... then again, it would be possible to fabricate a needle in this fashion, eh?
 
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V1 and V2 have them and the rebuild kits have them but the EPA V3 dosent have them its supposed to be a non tunable carb gotta love the EPA
 
Nightcruiser, if I sent you my CNS carb, could you tune it for me? I am at wit's end with mine, it will not work. Look up my other thread and you will see my problem.
 
Nightcruiser, if I sent you my CNS carb, could you tune it for me? I am at wit's end with mine, it will not work. Look up my other thread and you will see my problem.

You need to tune your carb to your motor. they all seem to have their own character, so I can't really do that for you....
I'll try to find your other thread and perhaps offer advice there if I have any...
 
My carb doesn't work period. I don't care if it's tuned to my motor or not. Nobody in NYC knows anything about this.....
 
im in NY and if you have a blue air filter CNS im sorry for you its a pain in the A$$ does it run at all or is the thing totally out of whack
 
It ran a little bit. Now it sputters and I tried adjusting the float. Contact me by PM and I will take it to you, maybe you can fix it?
 
My carb doesn't work period. I don't care if it's tuned to my motor or not. Nobody in NYC knows anything about this.....

I went and read your thread, you started out with a float setting that let too much fuel in the bowl from the description of how she ran when you turned your fuel valve off. You then made a float adjustment after which the carb was over flowing fuel, this was a move in the WRONG DIRECTION with your float adjustment. (or you lost your needle or inserted it backward, stick the pointed end into the valve) You need to get that needle valve under control and your motor will run.
In the meantime with the over flow situation you may have flooded out the motor, so you'll need to get your float setting/needle valve in check first and probably clear the flood from your motor before you get her running good......

PS Sometimes the floats can leak and take on fuel, the floats should be full of air, not fuel. Just thought I would throw that out there as well....
 
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It ran a little bit. Now it sputters and I tried adjusting the float. Contact me by PM and I will take it to you, maybe you can fix it?

Just go back at your float adjustment, you need to tighten that up so it only opens the needle valve a little bit, that will stop your fuel overflow and lean out your mix and get her running like it did while the fuel valve was turned off for that moment. Read back over my second post in this thread for whatever tips I have about adjusting the float, its pretty simple really....

PS this is a DIY hobby, you're gonna have to tackle this one yourself, I cant do it for you....
 
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as mentioned above, if you've flooded your motor it will run bad for a while and smoke a lot until you've run all the extra fuel out of the bottom of the cases

Oh, and you may get a small pool of fuel trapped in the bottom of some styles of muffler too which can be dumped by taking the bottom cap off.
 
since this was bumped
still using mine


later on when it was first insalled I had weird issues when it was under heavy use, it had a tiny intake leak
had to slather rtv sealant all over where it clamps on the intake tube
looks ugly, but seals it up great


now that its sealed runs so smooth
even after sitting 5 months starts right up, rides great

http://www.youtube.com/watch?v=EJUy2zgXDgY
 
Glad to have some testimony from folks that have been running the CNS carb and are happy with it, as am I. It gets tiresome hearing people say "throw it away" as soon as they hear the words "CNS carb". I love mine, although it took a little work to get it tuned up right, since then its been golden.

I would think it would be more appropriate to point a person in the right direction (like this thread) to get advice that can help them tune up their CNS carb rather than keep saying "throw it away".... or at very least warn people that the CNS carb is a bit more complicated than the NT or other single jet carbs, and it "may" be easier to tune an NT (or single jet carb) than the CNS, and let the person decide if they feel up to the task or not. Telling someone to "throw away" their carb seems to indicate it is garbage and can not be tuned to run well even if you try, which is anything but the truth....
 
as you say, there's been testimony that they can be made to work

what I haven't heard is any dyno or other readings that say it is better
 
as you say, there's been testimony that they can be made to work

what I haven't heard is any dyno or other readings that say it is better

Your not gonna read in this thread any claims that it is better than anything else (other than perhaps people may prefer the choke with the cable), or that it will increase the performance of a HT motor. It's just a thread about how to tune the carb that came with your kit rather than throwing it away and buying a different carb (as is so often suggested in this forum). If you take at face value some of what you read you would think there is nobody out there happily running the CNS carb, 'cause "its garbage and needs to be tossed in the trash" is a fairly accurate paraphrase. Thats not at all true, there are many happy motorized bicycle riders running the CNS carb....

Then again, I have seen the CNS carb selling as a "performance upgrade" for as much as $60, which I find completely ridiculous. If your kit came with an NT style carb there would be no reason to "upgrade" to the CNS carb, but likewise, if your kit came with the CNS carb there's no reason to change your carb either...
 
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