VM26 Specs Needed

I'm almost done rebuilding a set of VM26's and could use some help with the following:

- float height
- fuel level
- stock jetting : main and pilot. Currently 107.5 and 17.5. I realize that there may be different jetting for different years but wondering about a baseline.
- pilot fuel screw setting.

I don't know which model KZ these came from. They are just the standard VM26's. Nothing fancy.

Thanks in advance.

Looks like they are 77 KZ 1000 carbs. The KZ 900 had 115 mains, 17.5 pilots. The 1000 carbs had the same pilots. Needles on the 900 was 5DL31-3rd and the 1000 was 5CN8-3rd. Float level 22mm 900 vs 25mm 1000's. There's more for the later carbs as well. Seems they got leaner still.
Steve

What about the pilot fuel screw setting Steve? The screw has a plastic cap which allows about 1/8 of a turn for tuning.

1 3/8 +- 1/4 and 1 1/4 +- 1/4. I'll try to take a pic of the page in the morning. With the cap they sound later than these.
Steve

This camera doesn't take very sharp pics. Let me know if you can read it. I used paint but when you flip it, it gets worse.
Steve

Nessism wrote: I'm almost done rebuilding a set of VM26's and could use some help with the following:

- float height
- fuel level
- stock jetting : main and pilot. Currently 107.5 and 17.5. I realize that there may be different jetting for different years but wondering about a baseline.
- pilot fuel screw setting.

I don't know which model KZ these came from. They are just the standard VM26's. Nothing fancy.

Thanks in advance.

From the FSM covering Z1 through KZ900:







Good Fortune!

Nessism wrote: I'm almost done rebuilding a set of VM26's and could use some help with the following:

- float height
- fuel level...

The FSM manual doesn't address float height but it specifies that the fuel level should be 1/8" below the edge of the carburetor body.
Bill

Patton wrote:

Nessism wrote: I'm almost done rebuilding a set of VM26's and could use some help with the following:

- float height
- fuel level
- stock jetting : main and pilot. Currently 107.5 and 17.5. I realize that there may be different jetting for different years but wondering about a baseline.
- pilot fuel screw setting.

I don't know which model KZ these came from. They are just the standard VM26's. Nothing fancy.

Thanks in advance.

From the FSM covering Z1 through KZ900:

Good Fortune!

Not knowing what bike these carbs came from it is helpful to have the spcs from a full range of years. Ed what needle do you have. That might give a clue.
Steve

Thanks for the info guys.

I'll pull one of the needles and look for numbers, and provide some photos in a little while. I can tell you that these carbs don't have an air screw, just the fuel screw on the bottom.

P1030324 by nessism , on Flickr

P1030326 by nessism , on Flickr

P1030327 by nessism , on Flickr

P1030329 by nessism , on Flickr

P1030330 by nessism , on Flickr

This diagram may be helpful to viewers less acquainted with the different pilot circuits in Mikuni 26mm manual slide carbs:


Stock 1976 KZ900 has 26mm Mikuni with side-located pilot air screw.
Stock 1977 KZ1000-A1 and 1978 KZ1000-A2 have 26mm Mikuni with bottom-located pilot mixture screw.

Turning out pilot air screw adds air which leans the mixture.
Turning in pilot air screw reduces air which enriches the mixture.

Turning out pilot mixture screw adds mixture which enrichens the intake.
Turning in pilot mixture screw reduces mixture which leans the intake.

Per FSM covering 1977 KZ1000~1979 KZ1000:

1977 KZ1000-A1
Mikuni VM26SS (Pilot Mixture Screw)
Main Jet 107.5R
Needle Jet 0-6
Jet Needle 5CN8-3
Pilot Jet 17.5
Pilot screw 1¼ ± 1/8 turn out
Throttle Valve Cutaway 1.5
Design Fuel Level 32 ± 1mm
Service Fuel Level 3.0 ± 1mm

1978 KZ1000-A2
Mikuni VM26SS (Pilot Mixture Screw)
Main Jet 105R
Needle Jet 0-5/2
Jet Needle 5DL31-3
Pilot Jet 15
Pilot screw 1.0 ± 1/8 turn out
Throttle Valve Cutaway 1.5
Design Fuel Level 32 ± 1mm
Service Fuel Level 3.0 ± 1mm

A3 and D1-2 stock have VM28SS with side-located pilot air screw.





Good Fortune!