yet another CNS carb that doesnt work

decoherence said:

it never did anything for me.
i also have the "speed" carb. it runs well but its choke doesn't do anything to help either.
if i can get the enrichment circuit working on the cns, i will shorten the cable & mount it any where else that isn't the handle bars.

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The choke and/or enrichment circuits probably dont do much for you because you seem to be in Florida, I assume you have warm weather most of the time. I never needed the choke in the summer, as soon as it started dipping down around 60 and below the choke really became usefull to me.
Also, if the float is not adjusted properly the enrichment circuit on the CNS carb will act funny and be useless...

I'm almost sure nightcruiser has a valid point that the idle circuit jet and it's adjustment can have a big effect on everything in the lower range. still battling with the probs my cns has. I'm at an .0305" main jet now with the needle set all the way down for lean. It's too rich.
...But it's very reliable, and I'm reluctant to improve it from this point!
It takes abt 6-800ft to get it warmed up enough to quit pedalling, but that's ok! My enrichen circuit now has the cable removed to eliminate that potential problem.
I should switch the carb out, but I'm too stubborn... and having fun playing with this little puzzle. lol
Good luck
rc

rustycase said:

I'm almost sure nightcruiser has a valid point that the idle circuit jet and it's adjustment can have a big effect on everything in the lower range. still battling with the probs my cns has. I'm at an .0305" main jet now with the needle set all the way down for lean. It's too rich.
...But it's very reliable, and I'm reluctant to improve it from this point!
It takes abt 6-800ft to get it warmed up enough to quit pedalling, but that's ok! My enrichen circuit now has the cable removed to eliminate that potential problem.
I should switch the carb out, but I'm too stubborn... and having fun playing with this little puzzle. lol
Good luck
rc

Click to expand...

In the cold when I am running that first 6-800ft I also have to pedal cause she runs rough, but if I pull the choke to open the enrichment circuit she smooths up enough to ride. I find myself using the enrichment circuit for that first stretch, after a very short run it is no longer needed. I haven't had any problems with the enrichment circuit, and find it useful for the above scenario, so I wouldn't recommend disabling it, I see no reason for that.....
The CNS carb is a different beast than the NT or "Speed" carb, they only have one jet while the CNS has three.... The PILOT JET is VERY IMPORTANT for the low speed range, if it is not letting enough gas through slow riding will be really rough, and you will probably have a hard time getting idle (idle screw all the way in??? not mine!).
I recently repaired an '87 Honda Elite 50 scooter that had been sitting more than 10 years. Quite a machine really, purrs like a kitten after sitting all those years. Anyways... While cleaning the carb I came across a strange electrical device they called an "Auto BiStarter". This is basically an electric plunger that opens up an enrichment circuit very similar to what is on the CNS carb, main difference is the Honda cirucit is automatic and the CNS circuit is manual. So the idea of having an enrichment circuit instead of an air choke is not really strange or new.....

nightcruiser said:

The choke and/or enrichment circuits probably dont do much for you because you seem to be in Florida, I assume you have warm weather most of the time. I never needed the choke in the summer, as soon as it started dipping down around 60 and below the choke really became usefull to me.
Also, if the float is not adjusted properly the enrichment circuit on the CNS carb will act funny and be useless...

Click to expand...

well in the heat of the afternoon both carbs start right up.
when the sun goes down & it is in the 70's, it can take a block to just fire up. then another 2 blocks to be able to give it some gas.
i have a feeling that it is also a humidity thing.
even though humidity is almost always high. the dew point is about 72 when the sun goes down.

also when it gets cold it doesn't help.
even though i'm in central fl, we had almost a month straight of waking up to ice on everything

Me 2 Me 2. I read in a nother thread how wonderful the cns was. Not my experience.

So far i have one tank of fuel burned and nothing has really changed. The idle was very fast so I lowered it with the idle screw. (the one that lets the plastic slide come down to a lower point.

The throttle is real sloppy even adjusted to the tightest. It takes 1/2 turn to pick up eng rpm. Rpm will increase for about a 1/4 and then the engine dies.

It's nothing like the old 50cc honda and i was expecting that.

I'm thinking new throttle of the motorcycle type and a new carb that works.

All ideas appreciated.

Dennis

Well, as you've seen from the threads, the NT is the next step up the ladder...

Ratchetbirds has a mikuni thread you might want to review.

I'm having great fun battling with my cns although I now have a pair of nt's I could run when I get totally frustrated.

The china girls are just so handy to work on...
Good thing! lol

Have fun
rc

Thanx, I just checked the price on the Mikuni VM16. Spendy, like wearing a $200 dollar tie with a $150 suit.

$70 at amaqzon.