OMG I have to tune a CNS!!! Help

droc089 said:
I notice after riding for about 10mins it starts to bog down. Is this a air issue, I've drilled the jet to #64 and have clip at the middle position. My spark plug is black but it's not gunking up, it's slightly wet but nothing serious. I've been running about a week now still breaking in.
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A possibilty could be the gas cap vent. I recently checked 4 stock tanks I have, and 2 had no vent at all and held a vacuum. 1 vented very slow. Only 1 of the 4 was vented well enough.

Try loosening the cap and see if it runs better.
 
DuctTapedGoat said:
Spray carb cleaner around the areas you think you're leaking at, primarily the intake and bottom of the carb at the bowl. It's like a buck an a half at wally world.

And to Droc089:

Black and wet is NOT good, break in or not. You need to lean out (not oil, but fuel).

If you bog after a certain amount of time, your fuel bowl isn't staying filled is what I would imagine. Check for pinches in your fuel line, clean your fuel filters and inlets. Adjust the tang on the floats.

If that all fails - there is a RES (reserve) marking on your gas tank petcock, use that in place of on and it will give you slightly more flow.
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thanks duct, the reason why I'm not worried about it being black is because after my first ride it has been that way every since and I couldn't clean it off. The wetness on it is very small, I've seen some picture of some bad ones. I think my float could be the couplet. Saturday after I drilled the carb out and put the float bowl back together, turned the gas on and gas came shooting out of everywhere on my carb. after opening the float bowl again a little prymind needle thing (don't know how else to describe it) popped out. I stuck it back in it place and had no more leaks, but could that have been the problem before. I rode it yesterday to work and it kinda bogged going there but was fine coming home.
 
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Here's a picture of my spark. Kinda hard to tell anything but it's got a brown color around the edge then the middle is black. The wetness is the brown.
 

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That's what mine looked like too. I took it out and scrubbed the h out of it with a wire brush. I ran close to 20 miles last weekend and was able to open it up full throttle. I haven't looked at it again. Tonight, I plan on taking apart the carb, cleaning and re-tightening everything back together. I'm going to make a better attempt at cleaning the spark plug again and see how everything goes.
 
Jetting should really be a last resort until you're sure the air leaks are solved - you can add fuel to match how much air is coming in, but it's kind of a workaround to the actual problem - which isn't that it feels like it's not getting enough fuel, but that there is too much air for how much fuel is being delivered.
 
I actually thought about drilling holes in the red cover, maybe that could compensate for the fuel level. or just get a air filter soon
 
Good point, DTG. I'll save my new jet until I trouble every possiblity... droc089, I tried drilling holes, but I have a clearance issue. What I ended up doing is taking off the black plastic waffle screen/grate piece and the black sponge, flipping them around and screwing it back together. The plastic piece clamps the mesh sponge on. Then, I wrapped a piece of inner tube around the edge and hose-clamped it on, sealing the edge (in my mind). Then finally, I stretched a single layer of pantyhose over the whole homemade filter assembly and secured with a rubber band. I feel like this traps a little more dust than the sponge alone. It doesn't seem restrictive and I don't know how I could get a better airflow to filtering ratio. If anyone thinks this is a good idea, I'll try to post pics. If not, please tell me I'm silly and what the best thing for low to no clearance and the best airflow is...
 
Also, is it a bad idea to use a semi-permanent gasket maker/sealant on the mating surfaces? I haven't taken a carb apart before. I'm confident that I can disassemble/ reassemble one and was wondering if it would eliminate any potential air leaks...
 
skrew37 said:
Also, is it a bad idea to use a semi-permanent gasket maker/sealant on the mating surfaces? I haven't taken a carb apart before. I'm confident that I can disassemble/ reassemble one and was wondering if it would eliminate any potential air leaks...
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You can use gasket sealer on the intake manifold/head connection. Some people put a little silicone sealer on the manifold before sliding the carb onto it.
 
I'll try that. I put an o-ring in there and it seems to work, but maybe it's leaking there. Couldn't hurt I guess. Also what I was wondering is if anyone tried sealer where the upper and lower halves of the carb come together. Is there a gasket in there already?
 
skrew37 said:
I'll try that. I put an o-ring in there and it seems to work, but maybe it's leaking there. Couldn't hurt I guess. Also what I was wondering is if anyone tried sealer where the upper and lower halves of the carb come together. Is there a gasket in there already?
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The float bowl does have a gasket. I doubt you would need to use any sealer there.
 
Would it be a good idea to run the C-clip on the lean side more like second from top, or the top since mine runs pretty rich, how bad will that kill the power side of things?
 
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