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CV Carb Tuning

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  #1  
Old 07-29-2012, 08:19 PM
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Default CV Carb Tuning

Searched for information, but have not found something to answer my questions. Had some DynoJet stuff for my carb and removed it all and put back in the OEM items.

*** '97 WG = SE heads, SE ignition, Andrews EV-27, TH 2-1, Speed's Performance+ A/C ***

1) Replaced all gaskets / o-rings.

2) Purchased new slide (metal vs. previous plastic) due to tears in diaphram. Drilled the hole in the bottom of the slide.

* #3 I have a question on the spring and slide movement.
3) Re-installed longer OEM spring > can not lift the slide up further than 1/2 way up with finger. Prior spring with the plastic slide I was able to lift it all the way up with my finger.

4) Running a 45 slow / 190 main - can get it to idle, but when I give it some throttle it'll cough a bit through the carb.

Any suggestions?
 
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Old 07-29-2012, 08:47 PM
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Try it with the spring and needle out, check the spring was properly seated in the boss under the carby top.
 
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Old 07-29-2012, 09:48 PM
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Originally Posted by Spanners39
Try it with the spring and needle out, check the spring was properly seated in the boss under the carby top.
for sure....as far as idle....turn your mixture screw back to 2 or 2 1/4.....start from there....did u git it back on the manifold right....could be sukkin air...your close
 
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Old 09-03-2012, 10:02 PM
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Still having a problem with the coughing when twisting the throttle. Idle is fine. Have pulled the carb apart - float bowl, accelerator pump / gasket, main jet, spring, slide / diaphram. All rubber parts have been replaced (this includes the slide).

If I lift the enrichner up, the bike runs - no hesitations or coughing. The rubber gaskets on the intake manifold are brand new. I did spray some WD-40 when twisting the throttle and it ran - not hesitation or coughing.

1) If I read correctly, I have an intake leak somewhere...most likely the intake manifold. (This is my first time working on a carb)

2) One other question - on the main jet holder, there is a small (silver in color) cylinder that the jet holder holds in place and that the the needle goes into. What is the correct orientation for the sliver item? It appears there is a larger and smaller end, but no discernible difference in the center.
 
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Old 09-03-2012, 10:22 PM
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The end that is countersunk (thinner sidewalls at end, bigger hole) faces up.
 
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Old 09-03-2012, 10:23 PM
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Your intake leak would be where the manifold joins each head, there is a triangular section O ring under each flange....they die after a time.
 
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Old 09-04-2012, 09:17 AM
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I will re-check the silver item and see if I have it oriented the correct way. I will try it without the spring and needle installed.

Yes, the potential leak with the intake manifold where it meets the head is where it appears to be. I purchased new rubber "O-ring" gaskets. Mine are not triangular on my '97 WG.

The gaskets have a tapered end that I have facing away from the cylinder - the "flat" side of the gasket is mated against the cylinder.

Thank you for the replies.
 
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Old 09-04-2012, 09:26 AM
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Could it be you need to go up one size on slow jet 48 coughing in the carb sounds like lean then you correct it with enrichner.
 
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Old 09-04-2012, 10:04 AM
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More than likely the needle jet (the silver thing) is in upside down. Did you have the accelerator pump apart?? You may have forgotten the little ball or it may not be seating properly. Do you get a squirt when you twist the throttle?????
John
 
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Old 09-04-2012, 12:17 PM
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Originally Posted by miacycles
More than likely the needle jet (the silver thing) is in upside down. Did you have the accelerator pump apart?? You may have forgotten the little ball or it may not be seating properly. Do you get a squirt when you twist the throttle?????
John
I did have the accelerator pump apart - replaced the rubber diaphram. I did twist the throttle (w/o air cleaner on) and could see fuel being sprayed. I also removed the float bowl and then the accelerator pump and re-checked and then used the metal "L" arm and pressed that into the pump area and did get fuel to spray.
 


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