Jet needle symptom

  • Maxbou92
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Jet needle symptom

20 Jun 2026 03:10
#925097
Good morning guys, whats the symptoms of a bad jet needle And what kind of jet is in the Vm28 with 5cn15 needle? Thank youu very much 
Kz750e 1980

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Re: Jet needle symptom

20 Jun 2026 08:58
#925107
I have some info that indicates the 5cn15 needle was stock on the vm28ss carbs on the 1978 Z1R. 

There should be an ID stamped on the carb set either below the choke lever on carb #1 or on the outside of carb #4 

If you were to post what the ID is on your set I may be able to provide more info about what they came stock on and what internals were.  
1977 KZ650 B1
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OLD KAW OWNERS SMILE ALOT
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Re: Jet needle symptom

20 Jun 2026 09:24
#925109
  Thank youu!! Thats weird, I look at your chart and my main was 102.5 and now I put 105 !! The number under the choke is 112-6
Kz750e 1980

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Re: Jet needle symptom

20 Jun 2026 09:26 - 20 Jun 2026 09:26
#925110
Carb #4 has that number
Kz750e 1980
Last edit: 20 Jun 2026 09:26 by Maxbou92.

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Re: Jet needle symptom

20 Jun 2026 09:49 - 20 Jun 2026 09:53
#925112
Again I have some info that indicates the carb set ID of 1126 was used stock on the 1980 Z1R for Canada It appears it also had the same 5cn15 needle and a needle jet of O 1 just like the 78 version of the Z1R
www.partzilla.com/catalog/kawasaki/motor...or-assy-canada-80-d3
www.partzilla.com/catalog/kawasaki/motor...r-parts-canada-80-d3
1977 KZ650 B1
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OLD KAW OWNERS SMILE ALOT
Last edit: 20 Jun 2026 09:53 by gd4now.
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Re: Jet needle symptom

20 Jun 2026 09:53
#925113
Whats the worn out symptoms?! Do you know if I could find these jet needles somewhere?
Kz750e 1980

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Re: Jet needle symptom

20 Jun 2026 10:17
#925114
On Niche website, I found 169 and 175 needle jet!! Which one is good for my vm ?! How Im supposed to do to change them?!
Kz750e 1980

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Re: Jet needle symptom

20 Jun 2026 10:19
#925115
Not sure how to respond to what sort of symptoms a worn out needle jet will show. I would assume it could be rich,  As to where to locate some of them I have not done any searches for it. But if I was attempting to find some I would use the following to search 
Kawasaki 16017-1011
1977 KZ650 B1
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Re: Jet needle symptom

20 Jun 2026 10:22
#925116
Yes I already have Part number but cannot find them !! I appreciate man
Kz750e 1980

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  • JT-NZ
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Re: Jet needle symptom

20 Jun 2026 14:36
#925122
The most obvious sign of a worn jet needle is running rich, particularly at idle or low speeds. With the wear in the needle, it allows more fuel to pass than it should, - more fuel = rich running. There is no fix other than new needles.

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Re: Jet needle symptom

20 Jun 2026 14:49
#925123
I suspect mine to be worn!! I lean out my needle and the AFR is still rich and 1/2 throttle jump to 13.5-14!! Is it the needle who worn out first or Needle jet?!
Kz750e 1980

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Re: Jet needle symptom

21 Jun 2026 16:36
#925140
Preferably both, but definitely the needles as a minimum.

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