Installing a 400ex carb on a z400

[ChuckMoe]

This weekend I am going to mount up a stock 400ex carb onto my z400. Have any of you done this?

I am curious to know:
Will I need a 400ex throttle assembly?
Will the carb with 400ex stock jetting be jetted correctly for a stock z400 with a yoshimura team Suzuki slip on?

Thanks in advance for your help.

[rob-u/21]

are you suppose to get more horsepower out of it or why do this

[ChuckMoe]

Yes, on the 400EX carb, both the slide and butterfly are acutated by the throttle cable - on the KFX carb, the butterfly is operated by the cable and the slide works purely off engine vacuum - i.e. you aren't really in control of the throttle.

Supposedly it is a 3 hp gain on the bottom.

[440exnacsracer]

though the slide works off engine vacuum, it is plastic and wont make a difference in power, it just makes the throttle easier. the reason youll get a 3 hp bottom end gain is because it is a smaller carb...in essence, youll loose alot of top end. since you have a performance exaust, i suggest you go with a larger carb....its your bike though. peace
Ben

[86atc250r]

Not exactly... The carb size difference is a negligable 0.5mm - there are other factors within the carb that will affect overall flow more than this small difference in diameter.

The 400EX carb also provides gains thru the mid and top as well as the bottom and gains in throttle response. It has been shown on the dyno to gain about 3hp on the bottom as well as about 1hp on the top.

CV carbs are bad for performance. Their purpose isn't simply "to make the throttle pull easier". With a CV carb you can whack the throttle open (which is connected to the butterfly), unfortunately though, it doesn't matter how far open the butterfly is if the slide is still blocking the air path because engine vacuum hasn't pulled it up.

CV carbs are for mellowing response, emissions (cruiser street bikes), and low performance applications (like utility ATVs) - not racing , aggressive riding, or just someone looking to get power out of their machine. CV carbs are also more difficult to tune than a "real" carb.

The 400EX carb is a cheap way to add performance to the Z400 - of course you could go to the FCR 39mm carb and gain a lot more, but you're also talking a lot more money as well.

[ZRider400]

so did you test it out?.....i seriously want to try this if it works.


can you get pics??

[ChuckMoe]

I didn't get to it this weekend. My bike is getting some frame work done. I will use this thread to post a review. I have faith in every word Gabe says. He really knows his stuff.

[UglyMotha™]

I find it funny but ironic that people are taking parts from the ex to make there z go, isn't there some other parts that people are putting on there z's from the ex's wasn't it like brakes or axles or somthing along those lines, i don't remember what exle is transferable:confused: