Single carb for 750 Twin

Hey everyone I'm looking into getting rid of the cv carbs for a round slide. My question is what size VM should I go with the bike is an 82 CSR bone stock? I was thinking a VM38 or 36. Thanks for the help in advance.

What you gain in one area, you'll lose in another. CV carbs are good for elevation changes and stingy on gas. I wouldn't do it.
Steve

If you are planing on going to a single carb in place of the duel carbs, I have considered that myself. Not going to be any performance gain but it might be easier to keep in tune after you get it right the first time. You still might be better off with the CV carb though.
Jerry

I have a 73 Triumph Tiger 750 twin which has a single Amal carb, period tests show it was as quick and in some quicker than the twin carb Bonneville, so a single carb can work nicely on a twin, however the Triumph engine was originally designed that way and so the intakes are very close together as opposed to an engine designed for twin carbs. Given you can get a nice flowing intake manifold then there should be little if disadvantage to running a single carb performance wise, it may well increase your low end performance.

Now with regard to the size of the carb, this is where I see a "fly in the ointment". In addition to buying another carb, likely getting a new throttle cable and then getting it to run correctly in terms of jets etc. you may find just getting your CV carbs correctly sorted is easier and cheaper. The CV carbs on the Japanese twins ran very nicely in the day and if cleaned and fitted with some new parts can continue to do so. So while the single carb like I have on my Triumph is a delight when it comes to maintenance and tuning, it was built that way, once you go none stock it can be a different story and getting your single carb to run as you would like it to, may end up being just as frustrating as your CV carbs, perhaps more so.

The Amal on the Triumph is a 30mm, if you do go the single carb route I wouldn't go too big or you will defeat the object of easy tuning that a single carb gives. Large carbs can give poor idle and poor starting, only providing a performance edge at the highest of rpms and usually poor mid range and bottom end. For 55 hp, I cant see you needing to go over 34mm, but perhaps someone with actual experience knows differently.

Redhawk4, I pretty much have to agree with you. It is probaby more trouble than it's worth unless you just like to play with projects like this. I doubt I will do anything like this. In 1967 I bought a new Triumph TR6 single carb 650. By going down one tooth on the countershaft sprocket I surprised a lot of Bonnevilles with that bike. I started on a dual carved 500 cc Triumph in 1964 when I was 21 years old and had motorcycles ever since.
Jerry

Someone tried it on this forum are 5 years ago with copper plumbing pipe.
I don't know what ever became of it though :huh:

My BSA Cyclone racing engine that I bought from Gary Nixon had twin carbs, and I don't know of anyone who ever raced a 2-cylinder BSA that used a single carb. Ed

650ed wrote: My BSA Cyclone racing engine that I bought from Gary Nixon had twin carbs, and I don't know of anyone who ever raced a 2-cylinder BSA that used a single carb. Ed

My Triumph Trident Cafe' had three, slightly hard to tune, small Amal carbs, Jardine headers, .040" overbore 12:1 Hepolite pistons, 4 or 5 larger tooth rear sprocket and the bike kicked ass....
Just learn how to tune and maintain the CV carbs and you'll be a lot happier.

I want to get rid of the air box and the bs34 carbs on mine doesn't have an air screw on it. I will be fabricating an intake and have a vm34 carb so really just need a cable.

No eBay APP ID and/or Cert ID defined in Kunena configurationThe air screws are probably hidden under anti-tamper aluminum plugs. carefully drill into them then pry 'em out.
check out the carb parts diagram at Kawasaki.com or partzilla.

Single carb. The Milkman made a manifold from copper tubing & put a single stromberg carb on his 750-4.
If you go with a cv carburetor, it might help to stabilize the air flow if you add an extender between the carb & air filter.

Air filter cover.

The amount of work necessary to switch over to a single carb setup will be about 10x that of simply cleaning the stock carbs and setting them up properly. jertho got it right; the only good reason to do something like this is simply because you like to experiment.

Nessism wrote: The amount of work necessary to switch over to a single carb setup will be about 10x that of simply cleaning the stock carbs and setting them up properly. jertho got it right; the only good reason to do something like this is simply because you like to experiment.

Exactly! If one has the engineering skills to build a proper single carb intake manifold and select and correctly tune a single carb as a replacement for a dual carb setup he must certainly possess the skills to simply clean and adjust a pair of stock carbs that are already engineered to work with that engine. Ed