will VM33SMOOTHBORES work for me?

i have a 76 kz900 bored to 1015 with 10:25 to 1 comp. pistons,,, Kerker 4 into 1 exhaust,,, pod filters,,, slightly larger cams, not sure lift but not crazy,,, dyna ignition,,, head was cleaned up a bit,,, but just cannot get the thing running right! Have crappy 26 carbs on now, and found a pair of 33's just not sure if they will work or not. If they will not with proper jetting, which carbs would suite me best! someone PLEASE help i have a project ive been working on for 3 years. some one help me bring this baby alive!!!!

Boose, VM33 Smoothbores will work, And with enough fiddling can eventually be made to provide a smooth & tractable ride. The problem is, They were designed for racing...And for that application they were great "in their day", Where mid to full throttle performance was paramount... Unfortunatly, the transition from idle to midrange was "less than optimum", One of the "characaristics" of VM carbs is that at lower rpms, TOO MUCH WRIST equals LESS POWER. (true of ALL mechanicly operated slides, but especially so when increasing carb bores, and in this case nearly 30%) Too Much Too soon, & engine vac.falls...thus bogs & "flat spot". Just KNOWING this may help... The abilty to Feed Throttle & judge power is a skill often overlooked in an era of fuel injection & CV carbs. 33's (like 29's) are dinosaurs, They were mighty in their day, But are aging and no longer in production.... Were I in your situation, I'd continue the fight with your' 26's, or if they're hopeless (it happens) cop a set of "police" cv 34's.(sorry) They slip right in, Jetting will be close, and "rider imput" is less critical. just my 2 c, luck G

The Bike/ Motor should run fine on those 26mm carbs, if set up right. You would have a much better street low/ mid range than the larger carbs. But the larger carbs would give better top end RPM power. But if it is not running right for other reasons, changing to a larger carb won't be the cure.

If you're looking to toss your 26mm carbs, let me know. I need a set for my racer project.

Stock 26mm Mikuni carbs on the KZ900 are imo among the world's most user-friendly carbs.
Relatively simple manual slide design.
Easily maintained.
Easily tuned.
Good performance.
Readily available parts.
Introduced before the ultra-lean carb settings mandated by EPA on later models.
No easily clogged accelerator pump mechanisms.
Cope with pods better than most.
Hold their tune for a very long time.
No frail expensive diaphragms to contend with.

Good Fortune!

Patton wrote: Stock 26mm Mikuni carbs on the KZ900 are imo among the world's most user-friendly carbs.
Relatively simple manual slide design.
Easily maintained.
Easily tuned.
Good performance.
Readily available parts.
Introduced before the ultra-lean carb settings mandated by EPA on later models.
Cope with pods better than most.
Hold their tune for a very long time.
No frail expensive diaphragms to contend with.

Good Fortune!

Exactly why I want to start with those on my project rather than the VM28's from the Z1's.

unless the vm33's price is too good to pass up, id keep at the 26's.
all statements above are true.
the 33's will work. but if u cant get the 26's to work u may have just as much trouble with the 33's.
spend some time learning about how to clean and tune the easy carbs before u try to upgrade.
there are lots of guys that will help u get the 26's running proper.

In my opinion if you cannot get VM26 to work properly you will likely have issues with 33mm smoothbores.

I have a similar 1105 motor. I had 33s on it and it haulled butt but I never could get them to idle right. I finally traded them for 29 smoothbores and am much happier with them. Id sell the 33s and fix the 26s myself. Theres no such thing as cant be fixed unless the throttle shafts are worn out. Something is plugged some where or floats set wrong. Im my opinion they are the best {1976} carbs made for a street bike. Your problem may also be in the ignition circuit some where, points, timing, advancer etc