Z1 - Single carb mod

All,

I'm thinking about trying to make an intake manifold, and use a single carb. I've found the room to make it happen. However, not wanting to re-invent the wheel (so to speak), I thought I'd see if anyone's done it.

My first swag has me thinking that I'd need a smooth 500CFM carb. I just don't know that I can get it to idle AND run at high RPM, though.

Any thoughts?

Anyone tried it?


Thanks,

It's been done and worked! In the archives I believe there should be a post.

Here's one post by Milkman: Stromberg CD carb



Post edited by: rstnick, at: 2006/05/30 21:21

Here's a pic of the one I made for my 650, works fine.
Ride safe,
Les

had to make it smaller


Post edited by: The Milkman, at: 2006/05/30 21:14

Thanks Rob,,, :laugh:

No problem Les. You still runnin this set up?

why?:whistle:

wireman wrote:

why?:whistle:

Compliments to the people that made it work, but it seems to me that it'd be one giant leap backward to the carb and intake manifold setups from the old Indian, Excelsior and Henderson straight fours...

The whole point of a ported head and smoothbore carbs is to give the atomised fuel/air mixture the straightest possible shot at the combustion chamber. The less the flow is disturbed, the more efficient the transfer.

My guess would be that the setup would work moderately well up to cruising speeds, perhaps a bit more - but the swirls and eddies induced by those 90 degree bends in the manifolds would choke the bejesus out of it with a good, stiff wank on the right grip.

But it is an interesting looking and worthy bit of benchtop experimentation...

First... Thanks for moving the post.


Why? It's a fair question.

One of the main issues with the Z1-KZ engine, in my opinion, is carb sync. Over the years, I've spent too much time, even being good at it, tinkering on carbs. I'd love to be able to have one unit to rebuild.

It's great that there appears to be proof of concept. It's very exciting that it worked with a less then optimal intake. Clearly, the path to the center is better then the path to the outsides. But hay, it worked!!!!

The next step it to make the intake manifold that's more of a plunum type intake with equal runners. I'm thinking of making a down draft intake, that will allow a small auto carb. From this point, I'll have a lot of options. One option might be something like a ~400cfm 4bbl carb. I just might get the throtle responce I'm looking for at mid-power, if I can control the opening of the last set. I've seen some slick 2bbl carbs, a bit smaller, that open in succesion.

Assuming that the above works, EFI is the next step. assuming I can tune a small auto carb, then it should be failry easy to make an open loop Throtle Body (GM) EFI system work. At that point, it will be about the fuel map. IF I can get an O2 sencer in the 4:1 collector, I might even be able to make a closed system work. The EFI would be pretty sweet, but it will take a bit of time to tune.

It's an intresting project. Though, I still don't know where the ari cleaner will go.




Post edited by: FEF, at: 2006/05/31 11:41

i saw a manifold for sale on ebay which used a single carb. it was a really nice cast chromed piece. the description said it was for a kz650 engine but used on a plane!!! if you look for custom plane parts i'm sure there is one around and you won't have to make a weird looking copper pipe fiting one. just thought you might want to know?

(no offense milkman, i actually kind of like the idea. it would look great on a ratted bobber or something?)

Could you make the manifold from a turbo setup work? They use a single carb.

That carb looks like a SU off a late Model MG or Triumph ?? I worked in a British sports car garage many years .. I saw that 650 manifold too , I thought it was a slick looking thing ,,I was always told that the Old Skool to the Best carb set up was mutipules ... I agree that you wouldnt thing the airflow to the outside two Cyl. would be all that good ,, But then Car manifolds ? and how the carb sits in the middle ??? anyway ,, Just throwing in my 2 cents

kawtoy wrote:

Could you make the manifold from a turbo setup work? They use a single carb.

just get the whole turbo kit while youre at it:evil:

but more on topic, maybe some old 4-1 pipes cut up would work, just sort of mirror the exhaust pipes for an intake. only shorter lol, but i would think the collector might come in handy...

Post edited by: 77KZ650, at: 2006/05/31 20:51