hey all I just got a new high performance carbie and im wondering what are all the open vents for I know one on the bottom is for fuel to come out off but what are the rest for. and Im having trouble the bike runs and idles but it seams sluggish and I have a fair bit of fuel coming out my run off value ideas cheers
after market high preformance carb help
- Thread starter westy
- Start date
This is why I dislike sellers who attach words like, 'high performance, 'race' and 'speed' to their products. Novice builders see those words and believe them and buy a product that probably isn't any better, or even as good as what they have already.
We might be able to help you if you can give us a brand name or type of the carburetor. It sounds like a Walbro or a Chinese knock-off of one. "High Performance" doesn't tell us much. Post a picture of the carb. That will help us help you.
Tom
We might be able to help you if you can give us a brand name or type of the carburetor. It sounds like a Walbro or a Chinese knock-off of one. "High Performance" doesn't tell us much. Post a picture of the carb. That will help us help you.
Tom
Sounds like you have a CNS carb.
If it is like most other carbs, the main jet is to big and your engine is running very rich and being so sluggish because it is 4 stroking terribly.
Reducing the size of the main jet is normally the cure for this problem if in fact that is what you have going on.
Map
If it is like most other carbs, the main jet is to big and your engine is running very rich and being so sluggish because it is 4 stroking terribly.
Reducing the size of the main jet is normally the cure for this problem if in fact that is what you have going on.
Map
When a 2 Stroke engine is running to rich on fuel it will start firing every other stroke rather than on every stroke, you know it's 4 stroking when power is down and the engine makes a blabbering sound rather than a steady buzz.
It sounds like what you will need to do is reduce the size of the main jet in the carb and once you get that right you'll likey see the power go up and the engine will run like it should.
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My CNS V3 also has "EPA" stamped on the bowl ---- which I find amusing, because it certainly used much more fuel in it's stock form and didn't run as good.
I've reduced my jet size considerably. I've also removed that brass plug by the air filter (it has a second adjuster needle beneath it that needs to be accessed).
I've reduced my jet size considerably. I've also removed that brass plug by the air filter (it has a second adjuster needle beneath it that needs to be accessed).
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Read through these threads and you should see what I do to reduce my jet size and how to test for when it is right.
http://motorbicycling.com/showthread.php?t=55463
http://motorbicycling.com/showthread.php?t=51691
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http://motorbicycling.com/showthread.php?t=55463
http://motorbicycling.com/showthread.php?t=51691
Map
I was hoping you would ring in here buddy, I knew you have had good results with your CNS carb and could give some excellent pointers on tuning it.
The CNS I have doesn't have a plug over the mixture screw but I see that the newer ones do, or at least some of them do, gasbike.net shows several models of the CNS and that is wwhere I remembered seeing them so I went there and cobbed the pic I posted here earlier.
Map
some of us just solder and redrill our jets instead of buying new ones and ending up with several sometimes that are never used. a cheap set of wire gauge bits, a small propane torch or cigarette lighter torch and a very small piece of solder and you can make whatever jet size you need in just a couple minutes using the one stock size jet.
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