Welcome, Guest
Username: Password: Remember me

TOPIC:

The rusty hulk 19 Jun 2020 10:01 #828463

  • 73z1
  • 73z1's Avatar Topic Author
  • Offline
  • Member
  • Member
  • Posts: 321
  • Thank you received: 60
Needle od is correct .099"
Jet needle .105" (perhaps .107")
Main jet is correct .044"
Cylinder #1 way to rich, suspected plunger, not sure now, something not right.

Please Log in or Create an account to join the conversation.

The rusty hulk 20 Jun 2020 06:27 #828514

  • slmjim+Z1BEBE
  • slmjim+Z1BEBE's Avatar
  • Offline
  • Member
  • Member
  • Enjoy Life! IT HAS AN EXPIRATION DATE!
  • Posts: 768
  • Thank you received: 353
Mmmm.... brain fart talking about the '75 carbs.

Assuming correct fuel level, swap plungers & see if the problem follows the plunger.

Good Ridin'
slmjim & Z1BEBE
A biker looks at your engine and chrome.
A Rider looks at your odometer and tags.

1973 Z1 x2
1973 Z1 "The Wounded Z" (For Sale)
1974 Z1-A x2
1975 Z1-B x2
1993 CB 750 Nighthawk x2
2009 ST1300A

www.kawasaki-z-classik.com
An enthusiast's forum focused exclusively
on all things Z1, Z2 and KZ900.

Please Log in or Create an account to join the conversation.

The rusty hulk 20 Jun 2020 07:07 #828516

  • 73z1
  • 73z1's Avatar Topic Author
  • Offline
  • Member
  • Member
  • Posts: 321
  • Thank you received: 60
I swapped plungers, #1 stayed very rich.
Disassembled carb #1 and measured parts with rods and micrometer.
Needle jet is .117" (.002" over size) other parts correct size.
I disassembled two more carbs this morning, needle jets are .115"
Hard to believe .002" has the effect I see.

Please Log in or Create an account to join the conversation.

The rusty hulk 21 Jun 2020 19:54 #828636

  • slmjim+Z1BEBE
  • slmjim+Z1BEBE's Avatar
  • Offline
  • Member
  • Member
  • Enjoy Life! IT HAS AN EXPIRATION DATE!
  • Posts: 768
  • Thank you received: 353
Yeah, .002 doesn't sound like enough to richen the mix by much. Of one was a real glutton for punishment, needle jets could be pressed out of another carb & swapped.

Voltage drop (usually through the ignition switch) at the coil primary can cause plug fouling, but that should manifest on all plugs. Is full battery voltage available at the coil primaries?

This might be a longshot, and will only work if you have the OEM clear tube fuel level tool or something similar for early Z1 carbs with the 17mm plugs:
With the carbs on the engine, install the tube tool on the suspect carb & secure the tube such that it can be easily seen & won't dump fuel. Start the bike & observe if vibration causes fuel level to rise above spec. If so, needle valve and/or seat might be suspect. Otherwise, we got nuthin' :huh: .

Good Ridin'
slmjim & Z1BEBE
A biker looks at your engine and chrome.
A Rider looks at your odometer and tags.

1973 Z1 x2
1973 Z1 "The Wounded Z" (For Sale)
1974 Z1-A x2
1975 Z1-B x2
1993 CB 750 Nighthawk x2
2009 ST1300A

www.kawasaki-z-classik.com
An enthusiast's forum focused exclusively
on all things Z1, Z2 and KZ900.

Please Log in or Create an account to join the conversation.

The rusty hulk 22 Jun 2020 05:23 #828648

  • hardrockminer
  • hardrockminer's Avatar
  • Offline
  • Sustaining Member
  • Sustaining Member
  • Posts: 1301
  • Thank you received: 399
Needle jets will wear over time due to the action of the needle on the downstream side of the jet. (It rubs.) This is a recommended check point in the Kawasaki carburetor training manual. It's one of the few wear parts in the carbs, and yes, a 0.002" gap will make a hell of a difference to fuel flow.

What about the needle? Is it a 5J9? It's important that the correct needle is used to provide the correct fuel flow. Maybe someone changed out that needle and replaced with something else?
I have a couple of Z1B's restored, an '80 KZ1000LTD restored, a 1981 KZ550 restored and a 2008 KLR 650 for off road fun. My wife has a 2019 Suzuki DR 650 for on and off road.

Please Log in or Create an account to join the conversation.

The rusty hulk 22 Jun 2020 07:20 #828654

  • Kidkawie
  • Kidkawie's Avatar
  • Offline
  • Member
  • Member
  • I bleed premix
  • Posts: 1801
  • Thank you received: 194
One of my 2 strokes had an issue running rich, like hardrockminer said, the needle jet was worn. From research, they wear oval. Not a replacement part for me so I had to buy a new carb.
1975 Z1 900
1994 KX250 Supermoto
2004 KX125

Please Log in or Create an account to join the conversation.

The rusty hulk 23 Jun 2020 04:25 #828711

  • 73z1
  • 73z1's Avatar Topic Author
  • Offline
  • Member
  • Member
  • Posts: 321
  • Thank you received: 60
Thanks for the comments.
#1 plug is tan with spare carb.
Currently have air screw at 2.5 turns out to lean mix, still very rich.
Ordered some needle jets, will report when they arrive.
I've owned ten of these, never seen this before.

Please Log in or Create an account to join the conversation.

The rusty hulk 29 Sep 2020 04:43 #835829

  • 73z1
  • 73z1's Avatar Topic Author
  • Offline
  • Member
  • Member
  • Posts: 321
  • Thank you received: 60
The rusty hulk, version 2020

Please Log in or Create an account to join the conversation.

The rusty hulk 29 Sep 2020 11:17 #835866

  • Mikaw
  • Mikaw's Avatar
  • Offline
  • Sustaining Member
  • Sustaining Member
  • Posts: 1908
  • Thank you received: 432
Hang on and don’t blink. The last one was over quickly.:woohoo:
1976 KZ 900 A4
1976 KZ 900 B1 LTD
1978 KZ 1000 B2 LTD
Kowledge Speaks, But Wisdom Listens.
Jimi Hendrix.

Please Log in or Create an account to join the conversation.

The rusty hulk 30 Sep 2020 08:38 #835911

  • 73z1
  • 73z1's Avatar Topic Author
  • Offline
  • Member
  • Member
  • Posts: 321
  • Thank you received: 60
>>> "Hang on and don’t blink. The last one was over quickly"
Working on Z1, H1, H2 at same time.
Wow, what a pile of parts !

Please Log in or Create an account to join the conversation.

Last edit: by 73z1.

The rusty hulk 30 Sep 2020 08:39 #835912

  • 73z1
  • 73z1's Avatar Topic Author
  • Offline
  • Member
  • Member
  • Posts: 321
  • Thank you received: 60

Please Log in or Create an account to join the conversation.

The rusty hulk 16 Oct 2020 14:16 #837019

  • 73z1
  • 73z1's Avatar Topic Author
  • Offline
  • Member
  • Member
  • Posts: 321
  • Thank you received: 60
Anyone seen this ?

Please Log in or Create an account to join the conversation.

Powered by Kunena Forum