Jet size

I was wondering what jets should be used with my setup. Its a kz900 with kerker exhaust and will have k&n pods. Right now im cleaning. The 2 right hand bowls were bone dry, and the left ones had varnish like junk. I was just trying to jet them while they were out.

What are current jet sizes?

If you have the stock 76 KZ900 carbs VM26SC, then just go up two sizes on the main jets... #17.5 pilots, 5DL31-3 jet needle and #120 mains. Those carbs are relatively rich from the factory and don't need much to run pods/pipes.

OK I cant figure out how to get the jet needle out. Can someone help?

chupinator wrote:

OK I cant figure out how to get the jet needle out. Can someone help?

Believe KZ900 came new with:

26mm (VM26SS) KZ900A4 & A5
Main Jet 115
Air Jet 1.0
Needle Jet O-6
Jet Needle 5DL31-3 (last number is the clip position)
Throttle valve (slide) 1.5mm cutaway
Pilot Jet 17.5
Air Screw setting 1 3/8 turns out

Wiredgeorge suggested 2 sizes larger main jet (being 120) with pilot and jet needle unchanged.

Question about current sizes is because maybe carbs have already been re-jetted (perhaps existing main jet is already 120).

The jet needle would usually be removed to change the clip to another position from the normal third clip (middle of five clip positions), unless need to verify clip position and number 5DL31-3 it came with.

For sure the jet needle? Forgive the question, but is the jet needle size or clip position an issue at this time? Or maybe one of the other jets? The needle jet (pressed into the carb body above the air bleed pipe in which the jet needle moves up and down) is not often removed by us amateurs. It's mostly the main jet and pilot jet removed for cleaning or replacement.

Want to be helpful, but uncertain.

Here's a diagram for reference.



Post edited by: Patton, at: 2007/05/16 20:38

Ok then, Ill leave the jet needle alone. Im just trying to clean it up right now.

The jet needles default factory setting is 5DL31-3 where the -3 means the 3rd slot. To remove the jet needles, you need to remove the slides. To remove the slides, pull the two rubber plugs in the ends of #1 and #4 carbs. Remove the lock between #1 and #2 carb on the slide rod by removing the 5mm screw and pushing the rod end slightly towards the #1 side of the assembly. The lock piece will just pull out. Then remove all five 5mm bolts; one screws into the bellcrank and the other four lock the slide mechanisms to the slide rod. Then push the rod to one side so that it is free of two of the slide mechanisms and just pull them out. To remove the jet needle, you need to remove the two 3mm or 4mm screws on the bottom of the slide. Once you have the arm off the jet needles are below. Do the two and then slide the slide rod in the other direction so it clears the other two slides and you can then pull those slides out and remove the two small screws in the slide well. Once you have the jet needle clip position adjusted, you can put things back together pretty much in the same way they came apart. I like to resync carbs after doing this because their slide heights will change when you remove the slides from the slide rod.