29mm SB mixture screw starting points

Just got my bike running after an entire top end rebuild. Not starting up too smoothly or idleing though.

Seems to be in the carbs as it peps up with some choke added in. I figured pilots right? But i just had these cleaned at the shop last year (bathed and all) and havent put gas into them until now. They were stored dry in a box.

So what are some basic starting points (turns out)with the carb adjusters for Mikuni 29 smooth bores? Rear air one and front fuel one? I dont have my synch sticks anymore, i know i need to get some and do that too, but I want to have a decent place to start with the air/fuel mixtures screws.

Here are my specs if it helps:

z1900 w/ wiesco 1075cc kit

Mikuni 29mm smoothies

Dyna Ignition/coils

Web Cams: 410degree lift, 277 deg duration

Emigo pod filers (K&N pods enroute)

H.B.E. (Denco) exhaust

First of all what main jets and pilot jets are in the carbs? If you put cams and a 1075 kit in the bike and did not rejet the carbs then that could be the issue also.

There were 2 long threads all about jetting and setting up VM29's within the last month here.
A search of the archive should bear fruit for your quandary.

Anything less than a 20 pilot will probably give you rough starts and poor low speed operation. At least that was the case on my 1000.Also make sure you have plenty of air flow. The stock airbox/muffler set up didn't provide enough air flow for me.

oldkaw79 wrote:

First of all what main jets and pilot jets are in the carbs? If you put cams and a 1075 kit in the bike and did not rejet the carbs then that could be the issue also.

No i definitely didn't rejet. I did just strip them down and an now crosseyed from trying to read them dang little numbers!! Here is what I got:

Pilot - 17.5

Main - R 115

Jet Needle - 5DL31 (clip in center position)

Air Jet - 6 (or 60 .. was hard as heel to read)

Throttle valve cutaway 1.5

Safe to assume I need a bigger pilot (20?) and main (125 or 130?)?
If i want a little more low end kick should i raise my needle up (clip the lowest position)?
What about that air jet, should i bumb that bigger?

My setup info is in my 1st post but I will have the K&N pods before i get the new jets. Thanks in advance for any advice.

-brian

I actually just read that long VM29 jetting trouble post. Between Wiredgeorge and Patton I think I may have just become a professional VM29 carb tuner!! That is great info!

From this all i got ..

• I will keep my 17.5 pilot (to start out with) maybe get the 20 for backup though)
• I will go 120 for my main
• clean the hell out of my air jet
• start my pilot air screw at 1/4 turn and go out from there

Hopefully it will work out! Let you know when the mains come in the mail .. to Z1enterprises I go!!

There were at least FOUR types of VM29 sold. One was for the CB750 so we won't go into those since the carb spacing is incorrect. A few days ago, an eBay seller (see auction 180132786083 seller A1rjohn) stated in his auction:

"they are very adaptable,either for the KAWASAKI ,SUZUKI,(similar carb spacing)or the YAMAHA and HONDA."

He has since added that the carbs were mounted on a Z1R but if you think about adapting VM29s, remember that the bracket that holds the four carbs determines their spacing and they MUST be fitted with the corresponding rod that actuates the slides. In other words VM29s are NOT adaptable very easily unless you have another bracket and rod. When I pointed this out to the seller and asked him what the spacing was, or to provide the ID mark on the assembly (which also identifies them), he told me to "piss off". Bwhahaha A1rjohn, if you are out there, keep in mind that God still loves you! bwhahahhahahaha

Anyway, just wanted to point out that there are DIFFERENCES in the various 29s out there. The other three types of 29s are the KZ650 type, the 900/1015cc type and the Suzuki type. The KZ650 type does have a different ID mark but is identical to the 900/1015 type except for pilot and main jet... slide cut out is the same. Both the 650 and 900/1015 type use a 1.5 slide cut out. What this means is that a #17.5 pilot jet at 1/4 turn out works well and you CAN use a larger pilot jet, such as a #20 with more turns out. The Suzuki VM29 is pretty much identical except for the slide but out... 2.0 as I recall (may be 2.5). You need to use a MUCH bigger pilot jet... #27.5 pilot jet with the air screws just about closed. (I don't have VM22/210 pilots in #30 but that would likely be the right one to start with)

All jetting above works with pods and 4 into 1 btw... The pilot jets don't change much if you do use the OEM airbox just need to turn the airscrews out a tad.

Thanks George! Your a wealth of knowledge man and I definitely appreciate that. Between what I read in all your and Pattons posts on the VM29 subject and reading my entire fual system section of my manual twice last night .. I feel like I can take on pretty much any carburation problem with sucess.
I am excited for my new jets and pods to get here to tinker and get my bike purring smooth!! I just ordered a remote tank and vaccum gauges so I can do the synching myself too.

-brian