29mm smoothbore question

When looking at the factory jetting for the 29s on Z1E site, I get two different pilot jet #s. Says #17.5 on early 29s and #25 on late 29s. I've seen Jeff Saunders post the same info on here before.
Does anyone on here know the actual difference in the carbs to warrant the larger pilot jet?
I would assume the main air bleed is a different size also, but the specs say the same for both, 0.9

Im not sure about their difference, but I would suspect different air jets. Also, dont know if it applies here, but, the old style jet sizing showed smaller numbers than the new styles. I have machinist drill bits I use to verify jet sizes. I could take a late model CV jet which says 32.5 and it has the same hole size as an old style jet which says 17.5 and a 15 is closer to 30 Not sure if that pertains to the diff. in 29's though

Hey OldSchool, thanks for the reply. I don't think that will apply to the Mic VM jets.
I did get a reply from Jeff, but like you and I know, the more brains we can pick the more info we can have on hand to pick through.
I am in the process of dialing these in with #20, 22.5s, and #25 pilots. I went straight to 25s and will work my way down if it's too rich.

This is what Jeff says:

No major differences.

As engines got bigger, Mikuni increased the size of jets.

That does make sense. And sometimes you can tell if your close on your pilots by how much time it takes to run without any choke on initial start up. From what I've noticed, the smoothbores choke circuit is usually a richer choke than the CV's have.
With CV's its pretty easy since you can look at your fuel adj. screws for a guide. If you had 4 turns out to run smooth, you are a bit lean, they should fall inbetween 1 1/2 to 2 1/2. Smoothies are a bit tougher. Those air screws seem to only work with in 3/4 turn, after that, they dont do anything.
If you can get a smooth idle around 1/2 turn to 3/4, you should be in the ball park I would suspect unless theres a weird needle issue.

:woohoo: :woohoo: :woohoo:
I just got through putting the 29s back on my KZ1000, and it is a totally different bike.
I've been fighting a lean pop since I started on this bike with 29s. New manifolds and a thorough cleaning and careful mechanical sync made it bearable to ride. Running 17.5 pilots, 1.5 cut away slides, and 120 mains. 1/2-3/4 turn out on air screw ran the best. Soso performance and crappy idle from a performance standpoint, low end sucked.
This last time I pulled them off, I went straight to 25 pilots and set the air screw to 1 1/2 turns out. Did nothing else. Put them on, fired it up and BAM! this thing doesn't even sound like the same bike. Idle is stronger than it ever was. Throttle response is, well, it HAZ throttle response now!!!! :woohoo: Much stronger just blipping the throttle.
Bike accelerates hard now, wanting to pick up the front wheel. Even after hearing all the KZ guys on here tell me they never had to run anything bigger than 17.5s in their smooth bores, I knew I needed more pilot jet. I mean everyone on here is telling me they run with 1/8 to 1/4 turn out on the air screws. These carbs are designed to flow a certain amount of air through the idle circuit to run right. If you're down to 1/8 turn from optimum of 1 1/2, that tells me something is wrong.
I just wish I would have done this the day the jets got here. I been looking around here for them for a month, they grew legs and walked away from where I had them and then I finally find them somewhere I would have never put 'em. :whistle: :pinch:

Relay flag....BRING IT!! :evil: