Best carb for a 1340?

[1340evo]

Just wondered what you guy's think. I have a stock (or so I think, the bike is std bore but may have had head work, and has V&H open shotguns) 1340 FXR motor running a CV carb, but did see on a invoive that came with the bike, the guy before me had bought a S&S for it.
Maybe he took it off and put the CV on to sell or maybe it didn't run right with the S&S?

anyway, I see a few coming up on E-bay every so often so thought It may be worth getting a S&S to try?

I guess for a stock bike with mods I need a Super E and not a G ??... ... so is the Super E big enough? 

And will it be any better / easier to tune than the CV carb?

Nothing wrong with the CV, I guess I'm just messing...

[thumper 823]

Unless you are really hoping it up  (Big Cam )  The CV is one fo the greatest carbs out there.
In fact, there are people making them work for the 143-inch engines (woods-   https://www.woodcarbs.com/  )

All CV compensate somewhat for altitude too, they are close as to a venturi injection as one can get.
The Mikuni is great also .  Very EZ to adjust.
If I had the choice it would be the CV.

[Buglet]

   CV is the way to go. Get it set up right and you will be good to go.

[chipthedonkey]

Never used one.  Which of (if any) of the cheap off-shore CV knock offs are any good?

[thumper 823]

Just say NO to Chinese crap.
It never works very well

[chipthedonkey]

Just say NO to Chinese crap.
It never works very well

Never had an excuse to mess with one.  This was my assumption so never had any great inclination to try either.  My go-to when having have a stock carb that was just beyond help was always a Mikuni.

[thumper 823]

Their only real problem is changing the Main jet as the float bowl has to be dropped.
A Muk is more EZ
But,..once you get her dialed in it is done forever ...Plus there SO MAMNY HD with these you should not have to guess.

Most dyno rooms will tell you they will support a 100 Horsepower.
SO..choices.

[JW113]

Just say NO to Chinese crap.
It never works very well

This is coming from someone that has never bought a chinese crap CV. I have.

As far as I can tell, they are no different than the original Keihin CV carb. I bought one from Ebay just to check it out. It has functioned identical to any Japanese made CV that I have ever owned. I have one on one of my favorite bikes, and it is functioning perfectly. Anybody that wants to badmouth these carburetors, please put up some evidence that they are not quality. My experience has found they are very good. But, you judge for your self.

-JW

[thumper 823]

Just say NO to Chinese crap.
It never works very well

This is coming from someone that has never bought a chinese crap CV. I have.

As far as I can tell, they are no different than the original Keihin CV carb. I bought one from Ebay just to check it out. It has functioned identical to any Japanese made CV that I have ever owned. I have one on one of my favorite bikes, and it is functioning perfectly. Anybody that wants to badmouth these carburetors, please put up some evidence that they are not quality. My experience has found they are very good. But, you judge for your self.

-JW

Just curious-- Honest question, -Have you ever hooked up an AFR to one and see what is going on?

The CV is like said all most fuel injection.  If you don't know what I mean-rock solid AfR numbers at all RPM ranges.
I have had a couple of chinease junkers come through and they never made it off the table.
You all do as you like, but counterfeit parts are just that.
That is one big reason not to support them

[Scotty]

As far as I can tell, they are no different than the original Keihin CV carb. I bought one from Ebay just to check it out. It has functioned identical to any Japanese made CV that I have ever owned. I have one on one of my favorite bikes, and it is functioning perfectly. Anybody that wants to badmouth these carburetors, please put up some evidence that they are not quality. My experience has found they are very good. But, you judge for your self.

-JW

Have had 2 here bought from Ebay and Amazon by 2 different people and they were crap. The jet threads were not CV standard so no genuine jets would thread in.
The needle area was fine but the finish of the slide area was atrocious.
Both were replaced with 2nd hand rebuilt genuine CV carbs which work perfectly.
Maybe you got lucky but judging by what I have seen I would not touch a Chinese CV, S&S or Mikuni knockoff.
It's not worth any ones time or cash to buy crap like that.

[thumper 823]

The Counterfeit Mukuini is the same way -POS
Ya gets what ya pay for.
Plus with all the hype of buying a Harley, buying  American and all the crap, why add Chinese to it?
This seems oxymoronic.

[hbkeith]

OP already has a CV , bike probally runs like "Potty mouth" because of the exhaust

[Hossamania]

To the OP's questions:
Yes, an "E" is plenty of carb if going S&S.
As far as tuning, I've not done an E, but I can't believe it is as simple as a CV.
Will the S&S be better? It likely will not as good gas mileage as the CV, really won't improve horsepower, doesn't self adjust to altitude changes as readily, but it does look better.

[Racepres]

To the OP's questions:
Yes, an "E" is plenty of carb if going S&S.
As far as tuning, I've not done an E, but I can't believe it is as simple as a CV.
Will the S&S be better? It likely will not as good gas mileage as the CV, really won't improve horsepower, doesn't self adjust to altitude changes as readily, but it does look better.

Agree... in Principal.
Stock 80 incher?? I have had great luck with just about any carb out there..
two things tho... I would Always use the late model "push on spogot" Evo Manifold.. which leaves one with CV, or there is the Qwiksilver II which I personally love, or the Mikuni, or... the Original Screamin Eagle [Andrews Flowmaster] comes in a spigot mount...
Preferably we do Not support the ~ "Copy That" industry..

[Winston Wolf]

The Mikuni HSR42 will drop right in to your existing CV setup, so it's the easiest swap.  It's also the best carburetor.  Back to back it with a CV, and you will notice a much crisper throttle, and it will always make more power.  The vacuum CV carb just doesn't have the throttle response like the Mikuni flat slide. You can really dial the HSR in too, literally to fuel injection levels. (I tune with a wide band)

The S&S E would also work, but they are not very tunable and all the ones I have seem to stumble. I can swap a Mikuni on my Super E bikes and all the problems instantly go away.  I'd probably use a modified CV before a super E, but honestly don't put anything other than HSR's on my stuff. (unless it's a chopper or restoration)

[thumper 823]

People get the idea that a carb is going to add horsepower...in most cases it never will at street drivable RPM.

It is nothing but a hole with smaller holes (venturies    Bernoulli's principle )  no magic involved unless one bolts on a toliston/ Linkert .
Then one might need a wand.

S&S is for sure caveman compared to a CV and Mukuni .
But with thunder jets etc they can be made to run.

[Winston Wolf]

To the OP's questions:
Yes, an "E" is plenty of carb if going S&S.
As far as tuning, I've not done an E, but I can't believe it is as simple as a CV.
Will the S&S be better? It likely will not as good gas mileage as the CV, really won't improve horsepower, doesn't self adjust to altitude changes as readily, but it does look better.

Agree... in Principal.
Stock 80 incher?? I have had great luck with just about any carb out there..
two things tho... I would Always use the late model "push on spogot" Evo Manifold.. which leaves one with CV, or there is the Qwiksilver II which I personally love, or the Mikuni, or... the Original Screamin Eagle [Andrews Flowmaster] comes in a spigot mount...
Preferably we do Not support the ~ "Copy That" industry..

On EVO's, I have both the Mikuni "Total Kit", which uses a Mikuni manifold (similar to an S&S) with a bolt on rubber adapter flange, and then an HSR specific air cleaner that bolts to the heads; and the Mikuni "Easy Kit" which uses a stock CV manifold and any stage 1 air filter for a head breather.   I agree, that the CV manifold set up is a bit better, but they both stick out basically the same amount.

[JW113]

Just curious-- Honest question, -Have you ever hooked up an AFR to one and see what is going on?

Yes. It's on my Ironhead, and used a Daytona Sensors WEGO to dial it in dead nuts on. It runs perfect. I can't speak to the other poor quality copies that Scotty mentioned, but the one I bought is in every way identical to the Keihin, which by the way is no longer made. So your choice is to roll the dice and buy a used and maybe worn out piece of junk, or take a risk and by one of these new copies. I did the later, and could not be happier.

Back to the OP: Keep the CV, as far as carburetors go, it doesn't get much better than that. As Thumper said, horsepower does not come from the carb, as along as it's sized for the motor. Which the CV is for any HD up to ~100 cubes. Mikuni is a nice carb, but it will make no more HP than a CV. The "aesthetics" are different, i.e. it does not have an air flow controlled slider, but some of us like how that takes the twitchyness out of the throttle action.

-JW

[thumper 823]

I am an avid knuckle buster in my little shop
if you look at my threads -not to brag but I have a very nicely moded Evo .
To the point-
Almost everyone says the Mukuni will out-accelerate the CV.
I personally can't find the difference.
I am sure a dyno report would confirm one way or the other.
It would be great if someone could share a comparison.
Things I HATE  about the Mukuni is it rattles!  (reversion with a cam)

Things I like -ease of jet change.

After I installed the DM 530  I could not to save my life get the CV to idle. Changed to Mikuni I had here laying around and viola it was cured.

Anyone else with that problem?

[JW113]

Did you try drilling an air bleed hole in the throttle plate of the CV?

-JW

[thumper 823]

Yes, to no avail.
I am sure there is just too much reversion going on...

[1340evo]

Okay, thanks for the info.. it was just a thought as I saw one for sale and my mate always used S&S and it started good on the kicker...
I will stick with my CV and spend the money of fuel

[thumper 823]

You will spend a lot less on fuel with a CV  compared to an S&S toilet

[Pirsch Fire Wagon]

CV - Dependable - Easy Setup Fuel Mileage Up Excellent on Stock with only a few minor modifications to make it user friendly - Most advanced - Good fuel mileage.

E - Easy Setup, but can be a pain, not much adjustment for fine tuning / Fuel Mileage Down

Mikuni - The best of all but, requires more patients. Jets are a piece of cake. Tab Adjustment not so much - Once the Ignition Module and it are liking each other, VERY hard to beat. And, when set, they perform far beyond the others for eons. Fuel Mileage Down. Very fast response when dialed in!

Honestly, the CV or Mikuni you won't be disappointed. "Sometimes" The S&S is just "okay"

[capn]

Having used all three S&S e is by far the easiest to tune