Z1 plunger replacement
- 73z1
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Z1 plunger replacement
01 Sep 2026 17:37
Is keyster the best option to fix leaking plungers?
Kawasaki Z1 Keyster 16016-010 CARBURETOR PLUNGER STARTER | eBay
Kawasaki Z1 Keyster 16016-010 CARBURETOR PLUNGER STARTER | eBay
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- Nessism
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Re: Z1 plunger replacement
01 Sep 2026 18:41
Zed has a seal replacement service. Asphalt (Clay) stacks small O-rings on the nub to make the seal. I make rubber donuts from viton sheet, and wrestle them in place inside the plunger. All of these are cheaper than new plungers. Pick your poison.
Ed
Carb O-ring Kits : www.kzrider.com/forum/14-vendor-forum/62...rburetor-o-ring-kits
www.kzrider.com/forum/faq-wiki/618026-new-owner-things-to-know
1981 KZ750E2
www.kzrider.com/forum/11-projects/604901...z750e-project-thread
Carb O-ring Kits : www.kzrider.com/forum/14-vendor-forum/62...rburetor-o-ring-kits
www.kzrider.com/forum/faq-wiki/618026-new-owner-things-to-know
1981 KZ750E2
www.kzrider.com/forum/11-projects/604901...z750e-project-thread
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- asphalt900
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Re: Z1 plunger replacement
02 Sep 2026 03:24
The Keyster plunger you are showing would apply only to the 147x series or early Big 17mm bowl main jet access nut. What version of carbs are you working on? Also noteworthy. While Keyster has attained a Good name with the most respectable pattern non-oem parts, they had issues too. I've ran across several choke plungers from Keyster that had their rubber sealing pads simply glued in place, only to just fall out in the original packaging, still NEW! Or NOT crimped in place like the original Mikuni versions they were designed to replace.
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- 73z1
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Re: Z1 plunger replacement
02 Sep 2026 03:44
Thanks for the replies.
For 74 Z1, plunger has spool.
Listing says 73 74 75, probably need more parts for 73 plunger.
For 74 Z1, plunger has spool.
Listing says 73 74 75, probably need more parts for 73 plunger.
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- asphalt900
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- 73z1
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- hardrockminer
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Re: Z1 plunger replacement
02 Sep 2026 04:41
I swear by Keyster kits but not their plungers. The ones I've bought don't have the pointy thing on the bottom so they don't seal as well as Mikuni.
I have several restored bikes along with a 2006 Goldwing with a sidecar.
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Re: Z1 plunger replacement
02 Sep 2026 05:42
Got it 73. The 1974 though used Both versions because 1974 was a split year. So that's why i asked initially. Try my oringy thingy, it works just fine and costs less then a pack of gum. Or can merely be used as a diagnostic measure to assure the choke is completely shutting off fuel from the bowl. I use them as a permanent fix though and have for decades. Several forum members have tried it also, they might chime in?
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- Nessism
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Re: Z1 plunger replacement
02 Sep 2026 07:37What size O-rings do you use, Clay? Maybe I'll start including them with my O-ring kits...Got it 73. The 1974 though used Both versions because 1974 was a split year. So that's why i asked initially. Try my oringy thingy, it works just fine and costs less then a pack of gum. Or can merely be used as a diagnostic measure to assure the choke is completely shutting off fuel from the bowl. I use them as a permanent fix though and have for decades. Several forum members have tried it also, they might chime in?
Ed
Carb O-ring Kits : www.kzrider.com/forum/14-vendor-forum/62...rburetor-o-ring-kits
www.kzrider.com/forum/faq-wiki/618026-new-owner-things-to-know
1981 KZ750E2
www.kzrider.com/forum/11-projects/604901...z750e-project-thread
Carb O-ring Kits : www.kzrider.com/forum/14-vendor-forum/62...rburetor-o-ring-kits
www.kzrider.com/forum/faq-wiki/618026-new-owner-things-to-know
1981 KZ750E2
www.kzrider.com/forum/11-projects/604901...z750e-project-thread
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Re: Z1 plunger replacement
02 Sep 2026 08:38
Here's a gist of the problems with the Keyster plungers also confirmed by Hardrocking miner ha. They just rattle out??
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- sf4t7
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Re: Z1 plunger replacement
03 Sep 2026 06:13
Tried Clay's oring method to seal the choke plungers, it worked perfectly. And even better, it's cheap! Just make sure to use viton orings and you'll probably never have to do them again.
Scotty
1974 Z1A
Yoshimura 987, 10.25:1
welded Z1 crank
Andrews 1X Cams
Delkevic 4 into 1
Superbike bars
530 conversion
1974 Z1A
Yoshimura 987, 10.25:1
welded Z1 crank
Andrews 1X Cams
Delkevic 4 into 1
Superbike bars
530 conversion
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Re: Z1 plunger replacement
Yesterday 00:59
For Nessism and anyone else wanting to try this. The orings are 1.5mmCS X 1.5mmID X 4.5mmOD. Ed when we talked you were wanting a -0XX size equivalent, i wouldn't have a clue on that info. You're the reigning O-Ring KING, i'm sure you have all that info available at quick reference!
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