32:1, bike ran really good after original fix (i.e. disconnecting line from breather to bowl and dropping the e-clip to bottom of needle valve) Now it seems to be acting up in mid-range and WOT..which I can't do very often anyway,Tampa is NOT bicycle friendly. I suppose most of my riding IS at low speed 'cause the roads scare the **** out of me....
CNS carb working great....
- Thread starter nightcruiser
- Start date
I think this link will be helpfull to you...
Spark Plugs
Since you ride at mid throttle your needle adjustment is what you need to look at. Follow the chart to identify what you have going on, then adjust the e-clip on the needle away from the point to lean up the mix, toward the point to richen the mix. (the more the needle is pulled up out of the jet the more fuel flows) I think you need to lean her up a bit and clean the plug and see how she rides and looks after a while of riding. If you are running rich and oil fouling the plug riding mid throttle a lot, when you go WOT it might not run well with the fouled plug (unless it is able to burn it clean on its own).
From what I am hearing I would guess that you need to move your e-clip up a slot or two. I would try the mid position and see how that goes...
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Will-Do, but I think I will wait 'til tomorrow, (just cracked a beer) and thanks for all your ongoing support for everyone dealing with these carbs. I probably would have just chalked it up to a lousy kit PERIOD and vowed to never buy Chinese again. You're the "Kane" of Chinese engines !!!! Remember David Carradine on Kung Fu?
I don't remember "Kung Fu", I have a completely different image when I think of David Carradine....
I misspelled "Caine" anyway, didn't check on it, but I usually smell pretty good I just can't pype .....
Moved up 2 notches on needle, took 20 mile test ride, time to check the plug (changed it, too) runs good, let you know about plug in a bit.
Glad you seem to have worked things out. Make sure you wait until the engine cools after riding before you pull your plug....
Just checked it, new plug-black as ****, not wet, just black. Mixture screw adjustment or higher on needle ?? 3rd from top now.
Check the plug chart I linked and find the one that matches most and see what it says....
Thanx for the link. My eyes aren't what they used to be, but if I had to pick one, I'd have to pick 1. When I first started riding it, I didn't have to choke it at all to start it, now I have to even after a short shut down---but just for a second or two. All in all, it looks like a possible choke problem...woe is me, what to do what to do !?!?
#1 is a wet oil fouled plug...
Keep in mind that guide is covering 4-stroke as well, so for instance "oil pumping past rings" would apply to 4-stroke and not these 2-stroke motors. Since the CNS carb doesnt have a choke you can't really have an "excessive choking" problem... Remeber, the CNS carb does not have a flap to choke off the air, it has an extra enrichment fuel jet that gets opened when you pull the choke to richen the mix with more fuel rather than less air.
I forget where you are located, but I never needed the "choke" at all until it started getting cooler, now I need it for the first couple seconds, thats it...
Since you seem to have a wet condition on your plug I can think of a couple directions you can explore....
1) continue to move the needle away from the point to keep leaning her out. You might try cleaning the plug then running her hot at WOT for a while and do a plug chop at WOT. This will tell you if the mix from the main jet is ok, cause the needle and pilot jet don't have much effect at WOT. If plug looks ok at WOT then I would continue to lean out the mid throttle with the needle. or....
2) You may need to do a float adjustment to lower the fuel level in the bowl of the carb. This from my experience tends to lean out the mix and move a wet plug into the dryer regions. My motor was running wet, not idling, dripping from exhaust etc until I did the float adjustment. Reread that section on my thread on tuning my carb....
3) Ignition trouble is also listed as a common cause of this plug condition. I know the stock spark plug wire and cap are total crap, are you still using the original parts there? My spark plug cap broke almost imediately and I replaced it with a high quality wire and boot from a car motor, so I don't have experience with what running the crappy wire and cap will do to your plug... But it is worth a mention here since ignition problems are a common cause of a wet oily plug...
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Thanx for your response. I didn't realize there was no choke flap (shows how observant I am) and being in Tampa, I've never started it with the temp. below 75 degrees so that was my thinking on the choke. As for the ignition possibilities, the first time I connected the plug wire the plastic boot practically dissolved. It came with a backup boot which I changed to, but my first thought was to replace it all with an automotive wire also, but being a sealed unit, I gave that up. How could you replace it without splicing, which I didn't think would be wise since the CDI is sealed ? But one step at a time. I remember your post about fuel coming from your exhaust which makes me wonder if 1- plug is too cold(.030)NGK BP6HS..2 float level too high or 3- keep moving the needle valve down, but 1 more notch and I'm back to factory settings and from what I've read, that hasn't worked for anybody. Tell me how you replaced the plug wire and boot, interested.
Where the plug wire goes into the CDI the wire simply screws down onto a wood screw, that makes the electrical connection and "kinda" holds the wire in place, no joke! The wire is also glued in there, some say very lightly but mine was glued in there pretty good.
Twist the wire as if you are threading it off of a screw, you will probably need to use some pliers, and if yours is as glued as mine the wire will probably break off pretty much at the base. I took some small tools, exacto knife, pointy nail etc and slowly picked out all that rubber from the old wire working from the center to the outer edge. Eventually you will see the tip of a wood screw emerge. Clean it out until the screw is visible and the hole is clean enough to thread a new wire in there.
Go to your local auto parts store and ask them to look at their single spark plug wires. I picked one that was two foot long and had a spark plug boot on both ends (it said it was a coil wire), cut it in half and had a plug wire and boot for two CDI's for $4 bucks!
Whatever wire you choose, prepare a nice streight cut on the end, apply some silicone sealer around the outside of the wire and thread it down onto the screw in the cdi. Apply some extra thick silicone around the outside of the wire where it mates to the CDI and let dry, your done... Now you got a REAL spark plug wire!!!
PS you will need to screw that cap back on your spark plug with the new wire.....
When I had too much fuel flowing and fuel coming out of the exhaust I needed to adjust the float so the fuel level in the bowl was lower......
First off I'd like to say great post on how to tweak the CNC cab. I'm finding it useful. How ever I ran into a bit of a snag. On your second post you said the float was a 3pcs unit...I have 4pcs? The float, pin, needle. and the arm. Is this common in CNC carb's?
Attachments
My float is one piece, the plastic float and arm are one unit. I know there have been a couple versions of the CNS carb though, so yours could be a bit different. All the same principles still apply....
New problem. I noticed fuel leaking out of the bottom (clear) line from the float bowl after parking it overnight. Never happened before.
Leaking now?
lol
Of course, Bill, it's a CNS !
It's just the float/needle valve...
As I've said earlier, after 3 or 4 times fiddling with the float tang adjustment, mine almost magically began working properly and I avoid even touching it now while I am working on the jetting.
It could be a very small bit of grit in the needle. Who knows...??? If you take it apart to clean it, you probably won't see anything. lol
If you don't have a filter in the fuel line, you should install one. The needle valve assembly is very small, and because of the spring loaded needle, and small size, it's not possible to lap the seat for best possible seal.
Best
rc
lol
Of course, Bill, it's a CNS !
It's just the float/needle valve...
As I've said earlier, after 3 or 4 times fiddling with the float tang adjustment, mine almost magically began working properly and I avoid even touching it now while I am working on the jetting.
It could be a very small bit of grit in the needle. Who knows...??? If you take it apart to clean it, you probably won't see anything. lol
If you don't have a filter in the fuel line, you should install one. The needle valve assembly is very small, and because of the spring loaded needle, and small size, it's not possible to lap the seat for best possible seal.
Best
rc
