manifold O-Rings

[Julio]

  I can ride the thug bitch but have to put up with the constant hiccup in low rpm range. aint bad after 70 mph.

If the float height is correct, backfires and hunting (hiccups) in the low circuit sometimes can be fixed by shimming the needle.
What do the plugs look like?

J

[76shuvlinoff]

I see you have points? Have you peeked behind the points plate and checked the advance springs?

There is considerable difference between the bore of the S&S manifold and the throat of a 40mm CV. I expected fuel to puddle there due to an assumed drop in velocity but it never seemed to affect my bike. I really liked the 40mm cv carb but somehow I am driven to overcome success and had to try a 44mm. It is much closer to the inner diameter of the S&S manifold but the only real plus I feel I got from it was a slightly higher top end.

Mark

[dirtymike]

I didn't even think of the float level Julio, Haven't got a book on CV. Can you give me some measurements or where i can find the info. Cant hurt to try shim the needle. Ive heard of doing it but never tried. Small SS washers i guess. 76, it does puddle in the manifold but not bad. The 158 S&S is probably more inline with the 44.  Trudging along Thanks Dirty

[76shuvlinoff]

Yeah I don't know what 158 relates to. My S&S manifolds are for E carbs.

Re: CV tuning, I was sent this quite a while back, not even sure who sent it to me now.

"  I've done quite a few and can share what I've learned so far. First if your not 100% sure your intake seals (o rings or bands) are good change 'em, save a headache chasing a leak. I start w 2 1/2 turns out on the low air screw (seems to be right most of the time), if the bike doesn't want to idle well, I open 1/4 turn at a time. Don't set the idle speed too low. Ride a little to warm it up, then, when warm, try part throttle low speed, say 2nd gear with throttle just cracked, like riding slow through town. If it wants to sneeze through carb or buck and chugs, open air screw a little at a time till it's smooth, rule of thumb, if more than 3 1/2 turns out, go up on int. jet, reset to 2 1/2 try it again. when that's all good, take a nice pull through the gears, not a real ball breaker just a nice strong pull to say 3/4 throttle, see how it acts, if response seems good it's time to check main. If it seems funky may need to change/shim needle, I've only needed to work with the needle on one bike. For the main, get good speed built up in high gear then whack it wide open, if it blubbers or pops in the pipes go down on main, if you let off slowly and it seems to pull harder or pick up speed, go up on main. This is my experience and be aware I'm at sea level so your jetting may vary. Hope this helps. "

If there was no reaction to the spray or propane you likely don't have a leak at those points.

Have to disagree there - I found that the spray/propane test not all that reliable.  It's useful to confirm that there is a leak, but won't confirm that there isn't one, if you know what I mean.  I've had poor running issues that passed the intake tests but "mysteriously" went away when I replaced the seals.

But I do agree that 5 turns out on the A/F screw means pilot is too small.  Think I remember reading anything over 4 and you should try the next size up. 

Dirty - 48/190 is the standard starting point for a CV on a shovel.  Think I ended up with 48/180 or 185 and that sportster needle cured the last off idle hiccup.  But seriously, do yourself a favor an ditch that rubber carb to manifold fitting for a solid press on adapter.

CraigArizona made a proper tool for pressure testing for leaks.

http://harleytechtalk.com/htt/index.php/topic,1020.0.html

and please pull that points plate to take a look at your advance weights and springs

[dirtymike]

Ill check the plugs after i shim this needle and get her started again Julio. It seems they where a bit suty but tan on the center. Ill taek a pic next time i get it running. know the float height and where to measure (from and to). I printed that out 76, ill give it a try. Going to snow here tonight. Got to get her inside. Thanks Dirty

[Julio]

DM

Here are are instructions on how to check/set the float height.

http://www.cv-performance.com/harley_float_setting/

J

[Racepres]

I see you have points? Have you peeked behind the points plate and checked the advance springs
Mark

Good point...Most Carburetor Problems...Aren't! The Problem is probably Elsewhere...

[dirtymike]

Checked the advance springs and weights last time it was running. All intact and working properly.I'll make sure again before the next start. Good time to clean and adjust while im there.  Thanks for the heads-up on the float setting Julio, Seems CVP has all the parts if i need them. Still pluggin away, I'll get it sooner or later. Have to work the house this weekend, Ill post soon. Thanks Dirty   

[dirtymike]

Set the float at 15 degrees to .430, mid range.


polished slide and found a burn, is this still usable. The diaphram looks good. ?

[dirtymike]

Anybody seen this, stumbled across it this weekend surfin the web
Harley CV carb mod

[Racepres]

If he is drilling the slide out...don't do it...
I hate youtube generally.

[dirtymike]

Pretty sure he did. Seem the tricks are to shim the needle shorten the spring and drill hole to 7/64. I haven't done any. Trying to find my drill index and see if the PO did. The needle was out of a sporster (N86F). Im wondering if my slide is still good with the mark on its side, may be a constant backfire? Back at it. Ordered some jets and a needle from CVP. Thanks Dirty

[Racepres]

Lots of folks doing all kinds of crazy "Potty mouth" to CV's...Mine works just fine [very well in fact] with a simple Adapter flange into a Stock Manifold with Phenolic block, an n65 needle [no shims] and proper jetting. Using an XL aircleaner housing with a K&N filter...Won't change anything unless it gets Physically broken!!!

[dirtymike]

Well i found a Billet Flange adapter from Drag PN#DS-289219,http://www.dragspecialties.com/search/?q=DS-289219&docType=product&submit=Search
I Believe all four of these are the same part.

[76shuvlinoff]

Depending on shipping costs that's probably cheaper than eBay, just make sure it's for whatever size (40mm?) carb you have.

And pick up a little JB weld.

Mark

[Racepres]

I have a Friend in that makes 'em [adapters]...Can't tell ya about others...But, I'll look.
Haven't looked at stock manifolds in a long time...but they used to be about free!!!

[Julio]

DM

This is what you're looking at from the Drag catalog.



This is what you have now.



Aren't they the same thing? 


This is what you need.



http://www.ebay.com/itm/Harley-CV-Carb-Flange-Shovelhead-Sportster-40mm-or-44mm-/141441911218?pt=Motorcycles_Parts_Accessories&hash=item20ee9849b2&vxp=mtr

J

[Racepres]

^^^ Yes...I concur! The real Adapter...Good thing someone is Paying attention...I take for granted too much!!!

[76shuvlinoff]

Yep, 

So what is that top one for? To mount the rubber boot?

[dirtymike]

Im not sure that the one from drag is a press fit but the one Julio found on ebay is press fit with JB weld. It also is shorter and will tuck the CV carb closer to the engine. In the PIC it shows the isolator block installed.For 38 bucks, aint bad. When you purchase it you tell them on Pay Pal which one(40mm or 44mm). Mine is a 27207-93A, it came off a 1995 FLT So all the research tells me its a 40mm. I haven't delt with CV's much, aint right sure what to measure to determine the size. Im thinking its the ID on the throat where you press fit the Carb Flange to. Mine measures 1 9/16 " which converts to 39.6875mm I'd say thats enough to 40 to call it good. This cold spell came at the right time, i cant(wont) ride in the cold anymore, so ill turn a few wrenches. Ill post as soon as i get some parts. Thanks Dirty    

[Racepres]

I think yer gonna be Much more Happier!!!

[dirtymike]

CVP went to SEMA (4-7 Nov) and i have to wait till the come back to get my parts . IDK about this, seems they would leave someone there to conduct business. I guess the money at SEMA is good.  Dirty 

[dirtymike]

I ordered the flange adapter that Julio recommended. Sure will be nice to only have two Allen heads to remove to take the carb off. have to find a press. Wondering if a 6" Vise will work.Might as well put it on first, CVP went on vacation. Oh well, i chalk it up to Morphy's law. The one thing I've learned about being in a hurry is you are the only one. kickin like a chikin,    Thanks Dirty

[76shuvlinoff]

I have the version in the bottom pic on both my 40mm and 44mm CVs. The 40mm I took into the shop to use the press. The 44mm I used my own 6" vise, no issues either time. Make sure you have it aligned like you want it. I don't think it comes back off easy.

I agree about using Allen head cap screws, makes it a lot easier if you have ball end long arm versions of the hex key. When mounting make sure the top flange bolt isn't too long or it'll bottom on the carb body and likely crack it or press it back off.

Mark

[dirtymike]

Thanks for the heads up 76, obstacles, where would we be without them (pure Bliss). If the adapter is the same width as what i have its going to fit well, if i use the isolator. If i omit the isolator I'll  have to trim off 1/4 inch from the Allen head bolt. Thanks Dirty