Mikuni BS34 question

I just cleaned our a 4-stack of BS34's for one of my KZ1000Ps. There's a
small, double-walled pipe that descends down from the carb body through the
float-bowl gasket that fits into a gallery in the float bowl made just for
it.

Can someone tell me what that pipe goes to? I tried to remove it by gently
twisting it with some pliers.. no joy. I cleaned it but the most I got was
carb cleaner blowing out the little side vents in it... it didn't exit
anyplace else. A tag wire bottoms out. Any insight greatly appreciated.

Mike


--
Mike W.
96 XR400
99 KZ1000P
70 CT70
71 KG 100 (Hodaka-powered)

 

That is probably your cold start enrichment (choke for us
old farts) tubes. They don't come out for normal service or
cleaning.

Lugnut

 

That's the fuel pickup tube/starter jet for the starting enrichener.
It doesn't come out, but if you spray Berryman B12 through it and get
a good stream, you'll have no problems.

 

Thank you - Mike


--
Mike W.
96 XR400
99 KZ1000P
70 CT70
71 KG 100 (Hodaka-powered)

 

Thank you... Seems I did that with the enrichener off... I got a good
stream out the little side holes in the thing but didn't touch the path
from the tube to the enrichener... think I should abort the re-assembly of
the bike and go back and hit that?

Mike


--
Mike W.
96 XR400
99 KZ1000P
70 CT70
71 KG 100 (Hodaka-powered)

 

That sounds like a good idea.

Somebody posted a link to a schematic drawing of the BS34 to this
group about a year ago, You might want to Google for that.

 

Thanks.. some bit flipped after the third failed rebuild... the bike ended
up on it's left side with half of my wrenches scattered around the garage.
I'm selling the 2KZP's, the XR and Beta off after making it 6 months and a
day without riding and through 3 rebuilds of the carb stack in two days.
Your help, and the others', was appreciated. Thanks.

Mike


--
Mike W.
96 XR400
99 KZ1000P
70 CT70
71 KG 100 (Hodaka-powered)

 

I think I "get" most of this carb now... there are three ports that supply
fuel/air at low rpm:

1. Idle-mixture port - working back from port, you have the mixture screw
fed by the pilot jet, which in turn is fed air from one of the little air
feeds on the side of the intake bell, and is fed fuel by a passage to the
main jet.

2. A pair of transition ports just upsteam of the butterfly. They appear to
connect back to the idle jet as well.

There is also the feed from the enrichener, but I'm not feeling I
understand this very well. The fuel pickup tube supplies fuel to
XXXXXXXXXXXXXXXXXXXXX when the enrichener is "on". Where do it go??? I
can't see carb cleaner pushing out of any of the ports with the enrichener
open or closed. The path, as revealed by the outside of the carb goes up
near the mixture screw but zero carb cleaner ever reveals up there when
sprayed under pressure.

I want to ensure this "starter circuit" is right be fore I button the damn
thing up for the 4th time. Any help would be sincerely appreciated.

Mike



--
Mike W.
96 XR400
99 KZ1000P
70 CT70
71 KG 100 (Hodaka-powered)

 

The outlet hole is large, and carb cleaner would just dribble out.

When you move the "choke" lever to ON, the enrichener plunger is
raised, allowing AIR to
flow through a large hole in the inlet bell. The air passage comes out
down stream of the
throttle butterfly.

The airflow through the enrichener passage sucks up gasoline like a
kid sucking milk through a straw.

 

AHHH!!!!! Once again I sabotage my understanding of something by not
challenging my own assumptions. I see where this goes now... what I thought
was merely a vacuum passage to the vacuum tap on top of the downstream part
of the carb actually carries the enrichening stream too. THANKS. It looks,
with only one coffee in me so far, as though this circuit actually picks
it's airflow off the underside of the diaphragm rather than the inlet bell,
but perhaps that connection will reveal too with another cup or two
Thanks... I really appreciate your help getting out of my fog.

Mike

--
Mike W.
96 XR400
99 KZ1000P
70 CT70
71 KG 100 (Hodaka-powered)

 

It's possible. The location of the enrichener air inlet and the pilot
air jet vary according to the carb model, and I have seen the inlets
in either the inlet bell or under the diaphragm.