Any Keihin carb folks in the house?

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5speed
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Any Keihin carb folks in the house?

#1

Post by 5speed »

working on a friends 2003 arctic cat 4x4 quad. the carb was leaking gas and thru some digging around I discovered her fuel petcock wasn't working anymore. replaced that and rebuilt the carb.
my problem is..I can't adjust the pilot screw because it's on the bottom of the carb and the starter is about an inch and a half below it.
I can't get anything in there to turn it.
I've found pilot screws online that have a knurled knob on them and that would solve my problem.
MY only issue is..the ones I found are for a Keihin cv carb but it mentions big bore harley's as the only bike they fit.
Her carb is a cvk 32.
does anyone know of a source for the thumb adjustable pilot screws for those carbs?
1982 1100 standard. (sold)
1986 Yamaha FJ1200
2000 Yamaha Roadstar
1976 GoldWing. running but not on the road
1978 Goldwing. future cafe project.
2019 Can-Am ryker (boss's new ride)

2002 Shadow American Classic(sold)
1983 Shadow 500. (sold)
ob1quixote
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Re: Any Keihin carb folks in the house?

#2

Post by ob1quixote »

1979 GL1000
2001 DRZ400
1983 CR480
And a few late '60's - early '70's British thumpers
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LuckyEddie
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Re: Any Keihin carb folks in the house?

#3

Post by LuckyEddie »

I have found some success in using a short hex shaft screwdriver bit. Gotta work quickly as things are usually rather warm for any comfort with that method.
LuckyEddie

1978 GL1000 Supercharged (Avitar)
1976 GL1000
1980 XS1100LG
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5speed
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Re: Any Keihin carb folks in the house?

#4

Post by 5speed »

tks. :)
1982 1100 standard. (sold)
1986 Yamaha FJ1200
2000 Yamaha Roadstar
1976 GoldWing. running but not on the road
1978 Goldwing. future cafe project.
2019 Can-Am ryker (boss's new ride)

2002 Shadow American Classic(sold)
1983 Shadow 500. (sold)
ob1quixote
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Re: Any Keihin carb folks in the house?

#5

Post by ob1quixote »

1979 GL1000
2001 DRZ400
1983 CR480
And a few late '60's - early '70's British thumpers
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5speed
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Re: Any Keihin carb folks in the house?

#6

Post by 5speed »

LuckyEddie wrote: Sat Sep 05, 2020 7:36 pm I have found some success in using a short hex shaft screwdriver bit. Gotta work quickly as things are usually rather warm for any comfort with that method.
I attempted that but there isn't enough room for the hex bit, wrench and my hand.
1982 1100 standard. (sold)
1986 Yamaha FJ1200
2000 Yamaha Roadstar
1976 GoldWing. running but not on the road
1978 Goldwing. future cafe project.
2019 Can-Am ryker (boss's new ride)

2002 Shadow American Classic(sold)
1983 Shadow 500. (sold)
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5speed
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Re: Any Keihin carb folks in the house?

#7

Post by 5speed »

ob1quixote wrote: Sun Sep 06, 2020 12:48 am Another good tool!

https://www.motionpro.com/product/08-0181
that is nice..but I don't need one except to tweak her carb..or else I would get one.
1982 1100 standard. (sold)
1986 Yamaha FJ1200
2000 Yamaha Roadstar
1976 GoldWing. running but not on the road
1978 Goldwing. future cafe project.
2019 Can-Am ryker (boss's new ride)

2002 Shadow American Classic(sold)
1983 Shadow 500. (sold)
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Re: Any Keihin carb folks in the house?

#8

Post by LuckyEddie »

5speed wrote: Sun Sep 06, 2020 4:36 pm
LuckyEddie wrote: Sat Sep 05, 2020 7:36 pm I have found some success in using a short hex shaft screwdriver bit. Gotta work quickly as things are usually rather warm for any comfort with that method.
I attempted that but there isn't enough room for the hex bit, wrench and my hand.
I don't use a wrench, just my fingers. There is only slight spring pressure on the screw.
LuckyEddie

1978 GL1000 Supercharged (Avitar)
1976 GL1000
1980 XS1100LG
1982 XV750J
1981 XV920RH
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5speed
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Re: Any Keihin carb folks in the house?

#9

Post by 5speed »

little update. I set the pilot screw at 1-1/4 turns out. I removed the starter to get access to it.
It starts right up cold with the choke and after it runs for a few minutes I can take the choke off and it will idle but if I give it any throttle it quits.
when I rebuilt the carb I noticed the starter jet was a #75. the one that came in the kit and from the factory is a #60.
I put the #75 back in assuming it was there for a reason.
any suggestions on what my next step should be as I'm at a loss. lol
1982 1100 standard. (sold)
1986 Yamaha FJ1200
2000 Yamaha Roadstar
1976 GoldWing. running but not on the road
1978 Goldwing. future cafe project.
2019 Can-Am ryker (boss's new ride)

2002 Shadow American Classic(sold)
1983 Shadow 500. (sold)
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Re: Any Keihin carb folks in the house?

#10

Post by pidjones »

Keihens on a '79 CB750F that I rescued had to have choke to start, would idle pretty good after that, but took a looong time to warm enough to accept throttle. If they have the accelerator pump, make sure it works and the jets are flowing. Same as GL Keihens, make sure slides move freely and all passages are open. I just rebuilt a couple RD400 Mikunis last week. Oh! were they nice to work on! They have a peaned in ball that has to be removed to clear one jet, but otherwise a dream to rebuild.
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5speed
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Re: Any Keihin carb folks in the house?

#11

Post by 5speed »

pidjones wrote: Sun Sep 13, 2020 9:20 am Keihens on a '79 CB750F that I rescued had to have choke to start, would idle pretty good after that, but took a looong time to warm enough to accept throttle. If they have the accelerator pump, make sure it works and the jets are flowing. Same as GL Keihens, make sure slides move freely and all passages are open. I just rebuilt a couple RD400 Mikunis last week. Oh! were they nice to work on! They have a peaned in ball that has to be removed to clear one jet, but otherwise a dream to rebuild.
Tks pidjones. I'll try it again tomorrow and let it idle for a while and see what it does. the slide moves freely and all the passages are open. I hit them all with carb cleaner and blew them out with 40 psi of air.
it's a cvk 32 carb. no accelerator pump.
1982 1100 standard. (sold)
1986 Yamaha FJ1200
2000 Yamaha Roadstar
1976 GoldWing. running but not on the road
1978 Goldwing. future cafe project.
2019 Can-Am ryker (boss's new ride)

2002 Shadow American Classic(sold)
1983 Shadow 500. (sold)
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5speed
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Re: Any Keihin carb folks in the house?

#12

Post by 5speed »

slight update. Still fighting with this. I removed the tube between the carb and airbox so I could see if the slide was moving. It is..but not smoothly. It's "fluttering" for lack of a better word when I give it some throttle. I'm thinking vacuum leak.
Sooooo..gonna take the carb off again and double check all the screws after i check the slide diaphragm for tears,holes,etc.
1982 1100 standard. (sold)
1986 Yamaha FJ1200
2000 Yamaha Roadstar
1976 GoldWing. running but not on the road
1978 Goldwing. future cafe project.
2019 Can-Am ryker (boss's new ride)

2002 Shadow American Classic(sold)
1983 Shadow 500. (sold)
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Re: Any Keihin carb folks in the house?

#13

Post by robin1731 »

See if you can find video on youtube of some slides working. At part throttle no load they do flutter. They are not steady.

.
1976 Goldwing Super Sport
1985 Honda Elite
1976 KZ900 Dragbike
1992 ZX7 Dragbike (KZ900 style motor w/NOS)
and a rotation of various purchases
Randakk approved Carb Rebuilder
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5speed
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Re: Any Keihin carb folks in the house?

#14

Post by 5speed »

robin1731 wrote: Mon Sep 21, 2020 2:02 pm See if you can find video on youtube of some slides working. At part throttle no load they do flutter. They are not steady.

.
tks robin. I think I may have found the problem..when I removed the carb to check it over the pilot screw was laying on the engine case.. :shock:
so I put it back in, tightened it gently and I could wiggle it. so I replaced it with the original one and it screwed in to the carb a lot further then the replacement one does.
surprising as I used an All Balls kit..
Going to put the carb back on tomorrow and cross my fingers that was the problem.
1982 1100 standard. (sold)
1986 Yamaha FJ1200
2000 Yamaha Roadstar
1976 GoldWing. running but not on the road
1978 Goldwing. future cafe project.
2019 Can-Am ryker (boss's new ride)

2002 Shadow American Classic(sold)
1983 Shadow 500. (sold)
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Re: Any Keihin carb folks in the house?

#15

Post by robin1731 »

5speed wrote: Mon Sep 21, 2020 3:38 pm
robin1731 wrote: Mon Sep 21, 2020 2:02 pm See if you can find video on youtube of some slides working. At part throttle no load they do flutter. They are not steady.

.
tks robin. I think I may have found the problem..when I removed the carb to check it over the pilot screw was laying on the engine case.. :shock:
so I put it back in, tightened it gently and I could wiggle it. so I replaced it with the original one and it screwed in to the carb a lot further then the replacement one does.
surprising as I used an All Balls kit..
Going to put the carb back on tomorrow and cross my fingers that was the problem.
Yeah, aftermarket kits for any carbs are pretty much a no-no. I'm thinking of starting a thread on something I found on a set of GL carbs this past week.

And yeah, a missing pilot screw will make them run pretty bad. lolol

.
1976 Goldwing Super Sport
1985 Honda Elite
1976 KZ900 Dragbike
1992 ZX7 Dragbike (KZ900 style motor w/NOS)
and a rotation of various purchases
Randakk approved Carb Rebuilder
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