TOPIC:

Any body have any input on changing the carb system from four individuals carbs to a single carb. I think motorcycles are the only engines I am aware of that use one carb per hole. with one carb there would be no sync-ing. Yes I know I will have to try a couple of different carbs but any thouights

Carb syncing takes maybe 20 minutes at the most (including drinking a beer). Building a manifold, finding just the right carb, trying to tune the carb to work well, etc. could take a year (or forever).

If you are trying to avoid syncing the carbs by moving to a single carb you are looking at starting a project much more complicated and involved than syncing. If nothing else, you would be better off paying someone to sync the carbs. It's not as if it needs to be done very often (maybe once every 10 years or so?)

No offense intended, but if you find syncing carbs, which is very simple to do, to be a difficult task I believe you will find designing a decent manifold and tuning a single carb for 4 cylinders to be an impossible task. Ed

No offense taken, Building the manifold should be no problem. Just air flow, need to get enough fuel to cylinders so as not to run to lean. I still have the org carbs so Im not sure what I will do, probly still build the manifold and try anyway

Ps what makes a motor cycle engine different from a 8 or 6 or my four cylider plane engine all have one carb

kraber wrote: Ps what makes a motor cycle engine different from a 8 or 6 or my four cylider plane engine all have one carb

You can adapt anything to anything with enough effort. The question is, does it improve anything? In this situation, the answer is NO....

My guess for using one carburetor per cylinder is for more precise fuel/air metering for superior throttle response & HP. That's my guess & I'm sticking to it.

From the old KZRider, The Milkman went w a single MG CD 150 carb on a KZ650.

KZR Archives by The Milkman --- My Stromberg carb pics and explanation update

I posted quite a while ago that I was going to make an attempt to replace my 4 mikuni carbs with one Stromberg CD carb off an MG.

Well, I finally got to work on it over the last couple weeks. I made up a manifold using 1 inch copper tubing, two 90 fittings for cylinders 1 and 4, two T's for cylinders 2 and 3.

When I posted my idea here I got mixed comments, some to go for it, some saying it was a waste of time. Being the tinkering soul that I am I had to try it.

I finally got it together this weekend. I haven't made the linkage for the accelerator or choke yet, but I had to try it out. So I cable tied the pull cable to the bike frame and ran a string to the accelerator linkage on the carb.

Of course I had to take it out for a ride. Went 26 miles on back roads here in Maine then got on I-95 on the way back. Checked the plugs several times on the trip for carbon build up. This is the first time I have ever ridden the bike where all tests showed light brown residue on them instead black.

Actually, I was pretty impressed with how good it ran. No hesitation, no spitting and sputtering, great acceleration, it was actually a treat to ride.

Now I just have to decide whether to use it or not and to make up some linkage for it if I do. I'll post some pics, tomorrow.

If nothing else, it was fun doing it. :D:D
Les

Here is a picture of the carb I used. It's a CD 150.

The one advantage I can think of syncing the carbs is not all cylenders run at the same rate. Port angle, compression differnces, wear etc. makes tuneing each carb ideal.
My two cents for whatever it's worth.
Steve

we sync carbs because each cylinder has a different performance, even in an 8 cylinder, a single carb eliminates the need for syncing.

I was wondering what a crb kit cost X 4.

Ps I know I am bucking the trend. Some years ago I saw a tubo-ed kz1000 and it had only one carb, I am not going to put a tubo I just like being different

Aircraft engines are designed to run at one constant low rpm for hours. Street motorcycles need to be able to run well from idle to redline. Your Kawasaki is also in a much higher state of tune then 99% of the aircraft engines. If you want your bike to be slower and less fun to ride a single carb is a great mod to try.

80B4 wrote: Aircraft engines are designed to run at one constant low rpm for hours. Street motorcycles need to be able to run well from idle to redline. Your Kawasaki is also in a much higher state of tune then 99% of the aircraft engines. If you want your bike to be slower and less fun to ride a single carb is a great mod to try.

Same with cars. High performance cars that used carbs nearly always had multiple carbs. In fact, I can't recall any top of the line performance cars that used a single carb. Ed

Just one example:

650ed wrote:

80B4 wrote: Aircraft engines are designed to run at one constant low rpm for hours. Street motorcycles need to be able to run well from idle to redline. Your Kawasaki is also in a much higher state of tune then 99% of the aircraft engines. If you want your bike to be slower and less fun to ride a single carb is a great mod to try.

Same with cars. High performance cars that used carbs nearly always had multiple carbs. In fact, I can't recall any top of the line performance cars that used a single carb. Ed

Just one example:

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Did you use top of the line performance cars and a picture of a Pontiac with 3 deuces in the same post?
Ls-6 454 in the 70 chevelle/L-88 427s were mostly single 4 barrel motors from gm,the original Lt-1 370hp 350s were single 4 motors,thats just a couple off the top of my head anyway
Motorcycle motors and car motors are 2 totally different animals as far as design and lay out.