Carb opinion

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Do you have pods, if so what jets are you running ?

For running pods you just need air corrector jets and go up a size from stock on the mains.
No need for any other mods, all other settings, pilot jets and needle position remain stock but use good quality free flowing pods such as K&N, S&B etc and not cheap chinese knock offs as these are generally restrictive .
Air corrector jets for Mikuni VM 24, 26 and 28mm round slide Mikunis. - KZRider Forum - KZRider, KZ, Z1 & Z Motorcycle Enthusiast's Forum
Air corrector jet kit.Kawasaki Z1,Z650,Z900,Z1000,Z1R.MK2, MIKUNI.LEDAR.PODS.K&N | eBay

 I'm going to see how it runs when I get it out on the road & go from there. Thanks for your input.
 

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If so then those are almost certainly off a KZ900.  Good carbs.  I have them on my 1980 KZ1000 LTD.  

Hardrockminer,

Do you have pods, if so what jets are you running ?

No, I don't have pods.  I use a Z1 airbox because it's so easy to install the carbs compared to the original airbox.  I also have a 4/1 exhaust.  From memory I think I have 107.5 main jets and 17.5 pilots.  The needles and needle jets are original to the carbs but I don't remember what setting for the needles.  The bike starts easily on choke and quickly stabilizes and idles well.  It pulls well in all gears but is a bit hard on gas.

OK thanks seems moving up one size on the main is what most have done.
 

wrote:

wrote:

Do you have pods, if so what jets are you running ?

For running pods you just need air corrector jets and go up a size from stock on the mains.
No need for any other mods, all other settings, pilot jets and needle position remain stock but use good quality free flowing pods such as K&N, S&B etc and not cheap chinese knock offs as these are generally restrictive .
Air corrector jets for Mikuni VM 24, 26 and 28mm round slide Mikunis. - KZRider Forum - KZRider, KZ, Z1 & Z Motorcycle Enthusiast's Forum
Air corrector jet kit.Kawasaki Z1,Z650,Z900,Z1000,Z1R.MK2, MIKUNI.LEDAR.PODS.K&N | eBay

I was checking the stock main jet size on the '79 LTD  102.5,  On a stock '76 KZ900  (which I believe used the Z12 carbs I have) 115
Given its a different displacement do I go up one size from 102.5 or 115 ?
Is there anyone running the Z12 00's on a KZ1000 with pods that could  chime in on what jets they have ?   Thanks
 

I am running 76 carbs on a KZ1000 LTD.  My mains are 107.5.  I don't have pods but I run a Z1 air intake, which provides more air than a stock KZ1000 airbox.  I also have a 4/1 header.  I'm running 17.5 pilots, which were stock size on those carbs.  My needles and needle jets are also stock.

I don't think it makes a whole lot of difference until you reach higher rpm.  At lower rpm the main jet is controlled by the needles and needle jets.  The annular difference between the two will restrict flow through the main jet until the needles are almost lifted out of the needle jets.

I recommend you get some of zed1015's air correctors and send him your choke plungers to refresh the seal on the bottom.  

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I was checking the stock main jet size on the '79 LTD  102.5,  On a stock '76 KZ900  (which I believe used the Z12 carbs I have) 115
Given its a different displacement do I go up one size from 102.5 or 115 ?
Is there anyone running the Z12 00's on a KZ1000 with pods that could  chime in on what jets they have ?   Thanks
 

Once you establish which model the carbs came off you should go up a size from the stock main jet size they were originally fitted.
You have to understand that all these KZ1000 (1015cc) engines (except the injection models) are all the same spec and the carb jetting only differs mainly to account for the different exhaust and airbox design and flow of  any particuar model and although once the intake and exhaust spec is altered they could all run the exact same jetting there are other internal carb differences between models such as slide cutaway, needle jet size, needle taper etc etc that govern the overall fueling so taking those into account the jetting increases should only follow on from your carb models original specs and not anothers.
As for the 900 carbs on a 1000.
The max stock oversize on a 900 motor is 70mm which equates to 1015cc and the original jetting is sufficient for the 10% capacity increase of the max stock compression overbores so will be fine on the stock 1000 motor which is also 1015cc.
If using the 900 carbs then go up a size from their stock jetting.
If you want to be on the safe side go up two sizes on the main to start with.
 

wrote:

wrote:

I was checking the stock main jet size on the '79 LTD  102.5,  On a stock '76 KZ900  (which I believe used the Z12 carbs I have) 115
Given its a different displacement do I go up one size from 102.5 or 115 ?
Is there anyone running the Z12 00's on a KZ1000 with pods that could  chime in on what jets they have ?   Thanks
 

Once you establish which model the carbs came off you should go up a size from the stock main jet size they were originally fitted.
You have to understand that all these KZ1000 (1015cc) engines (except the injection models) are all the same spec and the carb jetting only differs mainly to account for the different exhaust and airbox design and flow of  any particuar model and although once the intake and exhaust spec is altered they could all run the exact same jetting there are other internal carb differences between models such as slide cutaway, needle jet size, needle taper etc etc that govern the overall fueling so taking those into account the jetting increases should only follow on from your carb models original specs and not anothers.
As for the 900 carbs on a 1000.
The max stock oversize on a 900 motor is 70mm which equates to 1015cc and the original jetting is sufficient for the 10% capacity increase of the max stock compression overbores so will be fine on the stock 1000 motor which is also 1015cc.
If using the 900 carbs then go up a size from their stock jetting.
If you want to be on the safe side go up two sizes on the main to start with.


Great info thanks.

I see hardrockminer is using jets 2 sizes up so that is probably the way to go.

If it was too lean would it just not run properly or it could fry a piston ?

 

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Great info thanks.

I see hardrockminer is using jets 2 sizes up so that is probably the way to go.

If it was too lean would it just not run properly or it could fry a piston ?

 

It would have to be very lean to do any substantial damage, not a size either way.
I only suggest starting larger than what you should need as starting higher and working down is best practice .
Too rich will only lose you power and increase fuel usage so wherever you start on the main you should perform plug chops or dyno runs and adjust the main down until the A/F ratio is correct.
Beware that perfect jetting on the dyno can sometimes result in being lean in real world riding conditions so additional high speed chops should be performed after final dyno runs as a precaution.
With air correctors fitted to cure the off idle flat spot these also allow you to run a smaller main due to the way they adjust the fuel slope.

wrote:

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Great info thanks.

I see hardrockminer is using jets 2 sizes up so that is probably the way to go.

If it was too lean would it just not run properly or it could fry a piston ?

 

It would have to be very lean to do any substantial damage, not a size either way.
I only suggest starting larger than what you should need as starting higher and working down is best practice .
Too rich will only lose you power and increase fuel usage so wherever you start on the main you should perform plug chops or dyno runs and adjust the main down until the A/F ratio is correct.
Beware that perfect jetting on the dyno can sometimes result in being lean in real world riding conditions so additional high speed chops should be performed after final dyno runs as a precaution.
With air correctors fitted to cure the off idle flat spot these also allow you to run a smaller main due to the way they adjust the fuel slope.

Ok Thanks again