Z400 carb guide

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He said newer TECHNOLOGY. A 2004 warrior carb is still 80's technology.

That being said, the z400 carb is equally old technology, possibly more refined than vacuum operated carbs from the 70's and 80's but not anything signifigantly different.

I think I would still prefer the stock warrior carb though, I feel like CV carbs are street carbs, and don't really perform well for off-road applications. There's no direct link between the throttle and the slide so you will have a delay in throttle regardless of how it's tuned. They don't need an accelerator pump because it's impossible to bog one out by opening the throttle quickly since the carb has to wait for the vacuum from the intake to lift the slide. You can get the stock warrior BSM carb to respond pretty sharp if you get it tuned just right and they're less tempermental to tune than a CV. I have a CV in my Suzuki and can't wait for the day that I can afford to replace it with a flat slide.
 
Alright a final update on my carb setup after getting everything tuned to where it runs great and the plug reads good.

First off my elevation is 2000 ft and below (NJ isnt that high)
As for the warrior it is mainly stock but has the airbox lid removed with UNI filter installed, and a White Bros E Series exhaust.

Starter Jet: 72.5 (this jet only has an effect on the choke actually, but a raptor 350 is set at 70 and this was the closest I could get and it works fine)
Pilot Jet: 27.5 (stock pilot jet is 22.5 and was too lean for me, it wouldn't idle and would pop/backfire and then only run at idle with the choke on... typical lean pilot circuit sign)
Main Jet: 157.5 (may seem rich, but according to my plug and the way the engine reacts, its right on)
Needle: 2nd clip position - rich (the mid range just ran too lean and broke up at the stock position, at this position it runs the smoothest)

The bike is snappy and just keeps on pulling with this setup and I am very happy with it. Getting it running this way took some research and reading up on others that have done it, as well as some trial and error on my part.
 
Thanks to all who contributed to this thread!

I'm still waiting on all the parts before completing the swap out, but have already stretched the stock boot to fit the z400 carb.

I used an aluminum aerosol can (spray-on sunscreen) that was tapered at the top. I drilled out the nozzle to relieve pressure, emptied it, stretched the boot over it and carefully heated with a torch. Fits perfect now! Will report back once complete.
 
Finally got around to completing the Z400 carb conversion with help from this thread. Thanks guys!

I went with a 142.5 Main, 22.5 Pilot, and a 60 starter jet that came with the carb. The liberated Fuel Screw is 3 turns out. Starts on the first pop, and runs better than before, so I'm leaving it alone for now. I have the stock exhaust, and no holes in airbox. Low altitude and 95 degrees outside.

Also, my Z400 carb came with a short idle adjuster cable and thumb twist knob. I zip-tied it to the frame, and can easily access it with my right hand while riding.

I'd recommend this mod to anyone needing a new carb on their Warrior.
 
Would anyone care to share the differences/similarities between the Z400 carb & Raptor 350 carb? Everyones says they are the same but is the jetting the same? Also, do the jets from the Warrior carb work in the Z400 or Raptor carbs? I have like 4 different main sizes from stock 145-155.
 
All you get with this carb is extra throttle response and slightly gained power over stock the throttle response will be noticed but probaly not the power :) And its not 80s technology
 
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