single carb setup,is it possible?

[paulbaut]

is there anyone who did a single carb setup? This is pretty cool,no more synchro of those 4 carbs,you're just left to mind that single carb...

[Lunatic]

yes its possible

Yes its possible, but if you are having that much of an issue with your carbs coming out of sync, there is something else wrong wtih your bike. My carbs haven't been sync'd in 30,000 miles and it still idles down just fine.
Also, consider, that wtih the single carb, getting the intake runners and fuel distribution exactly the same for all four cyls is near impossible, in the end the single carb tuned its best will still not be as well carbureted as the four carb rack when ignored for 30,000 miles.
But again, yes it can and has been done. a CV keihn off of a late model HD ought to be sufficeint. Good luck and be sure to post photos.

[Ivan]

I want a quadrajet or a holley on mine. Maybe even a carter, but those were kinda screwy....

[Lunatic]

progressive two-barrel

Pintos had a progressive two barrel., If a person were determined to us a car carb, I'd think a progressive two-barrel would be the way to go.
I can admire the ingenuity that it takes to make the manifold and linkage, even if in the end it won't run as well as a well tuned factory carb rack.

[Ivan]

Lots of older small cars used progressive two barrels, like half a 4 barrel. That was to try and keep the mix on the lean side while cruising and up the mix when under power, as a way to keep the mileage in check. It really didn't work all that well.

If I were to put a single carb on my bike, it would probably be something like a Ford 2150. Just a regular two barrel.

What I really think would be the way to go would be a side draft Weber. Nearly infinitely tunable, and lots of parts around for doing just that.

[tarzan]

I don't think you could get a 4 barrel like a Q-JET or Carter restricted down enough to run good on a small CC engine like these.
I think some of the progressives did function well.Maybe one off the 2300 Fords or something like that would work.
I think the challenge of the whole thing would be to get the runners the same length and to flow the same so you have a consistent even flow of fuel to each cylinder.

[Ivan]

I think the answer there would be a plenum, with runners to each cylinder.

[DiverRay]

I think it would be easy! Just use a TURBO, with a single carb on the intake side of the pump, and connect the plumbing too the four intake manifolds!
Oh, Yeah, you need to plumb the exhaust side for the turbo, as well as oil in and return. The good news, you will have a LOT more HP when done, and only one carb to worry about!
(yes, this is somewhat of a joke. But I plan on putting a turbo on one of my XS1100's, so I AM doing research.)

[The Lorax]

if it wasn't a downdraft, you could use the carb off a 1st generation RX-7, it was a 465cfm downdraft 4 barrell, supplied the little 1.1liter wankle with enough fuel and air to get almost 2horses per cubic in (that was until the enviro-nazis got a hold of it and increased emissions restrictions, forcing Mazda to shrink the port sizes, thus limiting the available horsepower, but in '78, the 1.1 liter (67 cubic inch) rotary put out close to 130 horses. like I said, too bad it was a downdraft, I'm sure someone could figure out how to make it work....someone smarter than me anyway, I know better than to try, I'll just make a mess followed by a fire . then again, it might be fun to try . have a nice day and ride safe

[crazy steve]

is there anyone who did a single carb setup? This is pretty cool,no more synchro of those 4 carbs,you're just left to mind that single carb...

There was one in a thread a few months ago (sorry, I don't remember which one) where I think the manifold was built from plumbing fittings. I can't imagine that it worked all that well. But on most inline motors it's very difficult to get even mixture distribution with a single fuel point due to different intake runner length. With the packaging limitations on a bike, it's all but impossible unless you want tubing sticking out all over. About the only time this is really practical or effective is if you're running a turbo or blower setup.

Multi-cylinder bike single carb setups are seen on V-type motors but it's pretty easy to make the intake runners equal length on these, and that makes all the difference.

There's lots of other Pros and Cons with single vs multi carb setups, but manifold design is the biggy on bikes IMO.

'78E original owner

[Larrym]

Home Depot Ram Air

Steve,

Ya mean this one?









Never heard back from mav2 about how well it worked...

[crazy steve]

LOLOLOL!!!!

Low-budget 'Ram Air'......

Now that you mention this, I do remember this one. But there was another one w/one carb and he used copper pipe fittings; a bit more durable than ABS....

'78E original owner

[Spider]

LOLOLOL!!!!

Low-budget 'Ram Air'......

Now that you mention this, I do remember this one. But there was another one w/one carb and he used copper pipe fittings; a bit more durable than ABS....

'78E original owner

You may be thinking of the XJ forums. I recall seeing similar setups over there.

[paulbaut]

tnx 4 your inputs guys!...my mechanic and I will try to check if we can do a single carb on our 2nd XS1100 project build...i will post pix of the setup..

[Tdog]

Webber

Hi,
I've seen Webber side drafts used for what you want to do. Check their website for pricing. I think they'll be expensive though.
Regards,
Tdog