CV Carb Tuning

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Sep 7, 2012 | 11:47 AM

#21

GREENOHAWK69

Thread Starter

Grand HDF Member

Joined: Oct 2006

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From: DFW

Quote:

Originally Posted by Schex3x

(1)Something's wrong here, the slide should lift all the way with the stock spring, the plastic needle holder installed correct?
(2) Does your needle have a clip with grooves?

(3) This picture may help to see if parts are installed correctly.

(4) What size hole drilled in slide?(should leave it stock size)

(5) The nozzle (silver thing) should have the larger hole up.
Longer end up, it's a snug fit, should protude through the carb body, don't booger it up.
You may have a burr or something making it hard to line up and install.

(1) Slide is fine...was replaced (with metal one) as previous slide (plastic) had rips in the rubber diaphragm.

(2) No clips - went back to stock needle.

(3) & (5) I think I had this upside down. It fell out when I was disassembling [FNG at it again] and never knew the correct orientation.

(4) Drilled hole slightly larger as indicated on Nightrider.com: http://www.nightrider.com/biketech/hd_cv_mods.htm

Sep 7, 2012 | 03:09 PM

#22

92Fatty

Road Master

Joined: Jan 2008

Posts: 1,187

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From: Montgomery, AL

When you have it running spray some wd-40 around the intake seals to verify you are not sucking air at the manifold head junction. I drilled my slide like nightrider and never had any bogging issues. You now have the factory spring in the top? What needle is in there any numbers on it, any shims under it? The slide should move with no problem. 45 190 jetting shouldn't be a problem for bogging on the cv. Did you buy it with this running problem or has it just started over time?

Sep 7, 2012 | 04:10 PM

#23

GREENOHAWK69

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From: DFW

Quote:

Originally Posted by 92Fatty

That is the next area to look...I thought I rectified this, but I may not have.

I just replaced the factory spring with the DynoJet spring. It is the factory Jet Needle with two (2) washers as shims. I've moved the slide with my finger when re-installing and it does not take much effort to get it to move.

This was the same carb I was using before I got a hardon for the PSI carb - that did not work out (tuning issues). The PSI did not have this problem. Bogging issue is since I dis-assembled and rebuilt the carb. Also installed new rubber gaskets for the intake manifold.

Sep 7, 2012 | 08:50 PM

#24

92Fatty

Road Master

Joined: Jan 2008

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From: Montgomery, AL

How different is the Dyonjet spring than a factory spring? I've never ran the dynojet kit myself. If you have already swapped out your manifold to head gaskets I'd just get it warm and give the bolts a once over again for tightness when it is warm after spraying for leaks. Next how thick are your washers on your needle? Perhaps you have it raised too much and it is just pig rich. Since you were using nightrider where is your idle mixture screw adjusted at? Does idle change when you adjust the idle mixture screw?

I made me a tool for the intake bolts by cutting an allen wrench and use a wrench when tightening making sure as not to strip.

Sep 7, 2012 | 09:38 PM

#25

langwilliams

Elite HDF Member

Joined: Jul 2010

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From: Lorain Ohio

"Greenhawk, the 'silver item" or needle jet goes in very easily the wrong way, and is a very tight fit to seat the right way. If the internally beveled edge isn't facing up into the venturi, you have it upside down and will have just the symptoms you are talking about. It will go in correctly, it just takes patience to seat it as it is a very tight fit."

This bit me in the *** when I was having problems an took it apart to clean. I found it by comparing my carb to a used one a guy had laying around an noticed a lot more silver showing on his.

Sep 9, 2012 | 08:48 PM

#26

fxdxruss

Road Captain

Joined: Jun 2008

Posts: 507

Likes: 3

From: 2 miles from the Sun!

carb

Greenohawk, just read an article in "American Iron Garage" Do it yourself upgrades for Harleys. There was an article on the CV by Joe Minton. In it he said the a 42 slow speed jet was all that was needed and some shops put in a 45 and it will richen up the bike but it will bog off idle on acceleration. He also went on to say that replacing the needle w/ a sporty needle p/n 27094-88 is what is needed. Good reading try and find it if you can.
Russ

Sep 10, 2012 | 07:48 AM

#27

ptcruiser

Cruiser

Joined: Nov 2008

Posts: 139

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From: Beaver, OK. (No mans land)

I think I would start by looking at your timing and VOES It could be that your timing is to retarded. If timing is to retarded will make it slow to rev

Sep 30, 2012 | 04:21 PM

#28

GREENOHAWK69

Thread Starter

Grand HDF Member

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From: DFW

Finally got the cycle running. Went throught the carb again and had a friend assist me - pretty much all we did was drop the main jet from a 200 to a 190 and bingo. It started and ran fine. Funny thing is that I had previously dropped it to a 190, but had popping.

Oh well, it runs fine now and I learned a lot about the Keihin CV carb.

Thanks for everyone's help.