Looking for carbs

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Looking for carbs

13 Mar 2021 21:30
#844890
Need carbs for '81 kz305a CSR. Sorry I don't know any of the specific numbers on them.
1981 KZ305A CSR
Western Kentucky

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Re: Looking for carbs

14 Mar 2021 06:13 - 14 Mar 2021 06:13
#844894
Are your carburetors shot or what? If you've never done carb work before, it's not that hard. JBM Industries has the diaphragms.

From the diagrams at Partzilla the KZ305 CSR & Ltd models used the same carburetors.
You could probably use the carbs from the 83 GPz or any other 305.
Keihin CV32 carburetors are listed in the FSM.
Last edit: 14 Mar 2021 06:13 by martin_csr.
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Re: Looking for carbs

15 Mar 2021 20:20
#844976
I don't really know if they are totally shot, been going on what a buddy has told me. But for other reasons I'm thinking he's talkin out his butt.
Could not get it to idle below 1800 rpm. The idle adjustment screws had no effect what so ever. Was told the diaphragms were messed up and holding the "needles" open. Found that to be true, they were full of holes and patched with what I think was rubber cement. Cleaned that up and re-patched them with electrical tape, just to see if I could make it work till I could get new ones. It hasn't ran since and he said the "idle fuel supply" was blocked and would be easier to replace.
1981 KZ305A CSR
Western Kentucky

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  • TexasKZ
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Re: Looking for carbs

15 Mar 2021 22:09 - 15 Mar 2021 22:10
#844980
I am not sure what he means by the idle fuel supply, but if the bike sat unriddennfor a long time, it is quite likely that the low speed circuit is clogged with dried fuel. A careful cleaning will solve that. I do not see a spring in the picture. If the coil spring that sits on top of the diaphragm is missing, the slide may well stay up when the engine runs.
Bottom line is that the carbs may just need a full on cleaning, some new gaskets and o-rings, replacing the diaphragms and any missing parts, and adjusting. The diaphragms are pricy, but there is no guarantee that another set of used carbs will be any better than what you have.
Maybe you could carefully disassemble them, take some good pictures as you do, and let the folks here help you assess what you have.
1982 KZ1000 LTD parts donor
1981 KZ1000 LTD awaiting resurrection
2000 ZRX1100 not ridden enough

www.kzrider.com/11-projects/620336-anoth...uild-thread?start=24
Last edit: 15 Mar 2021 22:10 by TexasKZ.

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Re: Looking for carbs

15 Mar 2021 22:15
#844981
Laying everything out carefully and in an organized fashion will help.

1982 KZ1000 LTD parts donor
1981 KZ1000 LTD awaiting resurrection
2000 ZRX1100 not ridden enough

www.kzrider.com/11-projects/620336-anoth...uild-thread?start=24

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Re: Looking for carbs

15 Mar 2021 22:22
#844982
Although this is a different model carb, it will give you a basic idea of what is supposed to go on in there. Notice on the right side of the carb, you will see the pilot jet, mixture screw and some small passages. They control the idle and low speed mixture. They are tiny and are easily clogged.

1982 KZ1000 LTD parts donor
1981 KZ1000 LTD awaiting resurrection
2000 ZRX1100 not ridden enough

www.kzrider.com/11-projects/620336-anoth...uild-thread?start=24

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Re: Looking for carbs

16 Mar 2021 10:18
#845006
That's most likely the problem. It would run great once it above about 2,000 rpm. I'll start taking them apart tonight after work and see if my cheap phone can take good enough pics, lol.
1981 KZ305A CSR
Western Kentucky

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Re: Looking for carbs

17 Mar 2021 13:35
#845093
Can we get this thread moved to a better topic, or should I start a new one about rebuilding these things?
1981 KZ305A CSR
Western Kentucky

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Re: Looking for carbs

17 Mar 2021 13:43
#845094
Cool breakout. Haven't seen that one
1978 kz1105 - the Rooster, 1981 KZ750 Chopper, 1975 KZ400 , 1984 GPZ750

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Re: Looking for carbs

17 Mar 2021 18:14
#845112
Cool breakout. Haven't seen that one
I stole it from Gazzz.
1982 KZ1000 LTD parts donor
1981 KZ1000 LTD awaiting resurrection
2000 ZRX1100 not ridden enough

www.kzrider.com/11-projects/620336-anoth...uild-thread?start=24

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Re: Looking for carbs

17 Mar 2021 22:32 - 17 Mar 2021 22:34
#845127
Even after it sat in the basement for 8 or 9 months, the float bowls were still full of gas.
1981 KZ305A CSR
Western Kentucky

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Last edit: 17 Mar 2021 22:34 by Stumpy4u.

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Re: Looking for carbs

18 Mar 2021 02:03
#845130
Nothing like a face full of carb cleaner to make your day... And before anyone freaks, I'm fine. Hit my cheek and splashed up under my glasses. I went right to the shower and crawled in and rinsed my eye till it stoped hurting and was clear again.
Now for the reason I'm here.

The small port between nozzle and pilot jet is clear so I stuck the carb cleaner tube up in the pilot jet. After I took the jet out and backed the mixture screw most the way out.

Should there be a spray of cleaner in the bore, or is seepage ok?
1981 KZ305A CSR
Western Kentucky

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