KZ 400 trouble

[2_DONE_THE_TON]

Hey guys!

Just figured that my KZ 400 has a gas leak between the two float bowls (inlet where gas enters the two float bowls).How can I change the seal, is there even a seal in there? looks like there are O Rings in there..32 in the pic below.
Looks like my right float bowl constantly gets less fuel than my left one due to this leak.

I´m currently running a full trouble shooting on my KZ, it has starting issues,it starts bad.
It only comes to life when I pull full choke and keep on gassing it.

Ignition timing and valves just have been checked.
Carbs cleaned and float height set.

Pulling the plugs it looks like one cylinder is running leaner than the other one,thought fuel starvation could be the issue.

One cylinder heats up faster,fresh new plugs and plugs that go onto the spark plugs.
Oh and membranes of the carbs are spotless

Stock carbs with K+N filters (I know that these will be hard to run on these carbs).
No air leaks (checked with brake cleaner around the carb boots).

Hope you guys can help!

 

[cxman]

ryan

what you are describing is a plugged idle circuit

these carbs need the emulsion tubes pulled the slow jet extracted and to be ultra sonic cleaned

and with the pods you will need to up jet

you can change the orings on the fuel transfer tube

 

[2_DONE_THE_TON]

ryan

what you are describing is a plugged idle circuit

these carbs need the emulsion tubes pulled the slow jet extracted and to be ultra sonic cleaned

and with the pods you will need to up jet

you can change the orings on the fuel transfer tube

thank you cx man for chiming in!

the idle jet circuit was my guess first too...i pulled the parts in the diagram 17,19 and 15 und thoroughly cleaned them.dunno if I cleaned the passageways.I will definitely go over the carbs as soon as possible.
I will replace the Orings in the inlet too,are there any other passages which need special treatment on these CV carbs.

The carbs were rejetted,I´m not sure if it was done properly, as I stated earlier one cylinder seems to run leaner than the other?
could a clogged slow jet circuit cause this?

 

[cxman]

yes one plugged idle circuit can cause most of this

make sure the jets are in the correct location big and small as both the mains are the same shape

look at the diagram to be sure of the larger ones placement

make sure the slow jet rubber plugs are good and in place

when you split the carbs to do the oring

make sure you check teh butterfly gap and do a rough bench sync after reassembly

 

[2_DONE_THE_TON]

yes one plugged idle circuit can cause most of this

make sure the jets are in the correct location big and small as both the mains are the same shape

look at the diagram to be sure of the larger ones placement

make sure the slow jet rubber plugs are good and in place

when you split the carbs to do the oring

make sure you check teh butterfly gap and do a rough bench sync after reassembly

ooops forgot to upload the diagram....parts 15, 19 and 17 are the ones which we are talking about right?
20 is the slow jet plug.

is there a bench setting for the mixture screws?

could you elaborate more on the bench snyching of the butterflies:
found this video,it is about a cb 350 carb but i guess those CV carbs are pretty similar...he uses a guitar string togap the butterflies.

there are two inlet on the carb (black plastic), the ones on which hose number 36 comes on,what should I do with them plug them or put a hose to them...are they vents?

thanks cxman!

 

[hillsy]

Bench sync with a guitar string or piece of wire is fine. Screw 21 is the balance between the carbs.


Dont plug those ports at #36 they are float bowl vents - put 2 hoses on them and route them down behind the engine.

 

[2_DONE_THE_TON]

Bench sync with a guitar string or piece of wire is fine. Screw 21 is the balance between the carbs.


Dont plug those ports at #36 they are float bowl vents - put 2 hoses on them and route them down behind the engine.

thanks hillsy!
any recommondation on the bench setting of the mixture screws?

 

[hillsy]

thanks hillsy!
any recommondation on the bench setting of the mixture screws?

Kinda depends on what size pilot jets are in there, but start at 2-2.5 turns out and see how you go.

 

[2_DONE_THE_TON]

Thanks guys!

I will let you know the results.
will it be sufficient to go trough all the orifices of the carb with carb cleaner and see if they are free or will I need to ultrasonic the dissassebled carb bodies?

My RD carbs have a tiny orifice which not even ultrasonic can open up (used a syringe with a needle and carb cleaner..worked a treat), so I dont really trust ultrasonic cleaning...

Yesterday is realised that one of the mufflers weren´t properly tightened (joint between muffler and downpipe) could this be related to the issues I have?

 

[2_DONE_THE_TON]

hey guys!

had a few minutes yesterday to inspect my carbs and take a look.made a few pics as well as a short video.

found the screw that seems actuates the arm for the butterflies of the carbs...had the feeling somehow that it only actuates the left side of the two butterflies..should this screw (marked red) actuate both butterflies?

took a look at some diagrams and it looks like these tiny orifices of that get blocked by the butterflies are the pilot jet openings...

https://www.youtube.com/watch?v=f906PWMDX6U&feature=youtu.be

 

[canyoncarver]

As hillsy said, that screw is to balance the both carbs butterfly's to each other.

 

[2_DONE_THE_TON]

As hillsy said, that screw is to balance the both carbs butterfly's to each other.

unforunately this screw just moves the butterfly of one of the carbs (see video).
the other one is untouched by the adjustment.

just checked out some videos on youtube, my guess is that the other carb butterfly gets set by the idle adjustment screw.

first: adjust idle screw on right carb,gap it with guitar string
second:adjust left carb with adjuster screw,screw down retainer nut.

 

[cxman]

yup and snug the lock nut and then snap the throttle open and let it spring closed a few times

adjust it again till its good

 

[2_DONE_THE_TON]

yup and snug the lock nut and then snap the throttle open and let it spring closed a few times

adjust it again till its good

Any tips on how to clean the pilot jet orifices drilled in the carb body?they are pretty hard to get to...
Thought about brake cleaner and some pressured air...

 

[cxman]

if you can find a blow gun that you can screw a ball needle inflator on to it will fit down the passages and do a good job

brake cleaner helps to

if they are plugged still i often will go old school and boil them in distilled water with a bit of lemon juice

then rinse well or they can discolor

 

[jpmobius]

I am not able to get anything from the video(??). Looks like the screw you circled (as has been already noted) is the adjustment that synchronizes the two butterflies. The cable should directly operate the one carb, and the second carb connects to it mechanically at the adjuster.

 

[2_DONE_THE_TON]

How thick should the guitar string be to bench sync the carbs?does it make a difference really,i guess when i use a thicker wire the idle will get up.

 

[cxman]

once you get them both to the same level when you advance or reduce the idle speed both will move in unison

 

[2_DONE_THE_TON]

So guys i had time today to go trough the carbs.
Full clean out.i went trough all jets orifices and what I could find to blow out

Tried to sync the butterfly but it is strange.
In the video I saw about the cb carbs the one butterfly(idle screw) was fullu adjustable,easy to put a guitar string in there and sync the other one to that gap.

On my carb,even when I screw the idle screw all the way in,the gap was minimal (first pic).

Then i tried to start the bike in a setting i thought that would be sync,it started well,revved really high,tried to adjust the idle screw,if i gassed the bike it would die.
Guess i messed up....

First two pics show carb when idle screw all the way i
Other pics idle screw all the way backed out

 

[cxman]

your sync screw is not pushing the one butterfly closed

where do you live?

here are some not bad pics of un molested carbs maybe they will help

http://www.ebay.co.uk/itm/like/281936875847?clk_rvr_id=985313097938&item=281936875847&lgeo=1&vectorid=229508&rmvSB=true