Mikuni RS34 carbs
- TexasKZ
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Re: Mikuni RS34 carbs
12 Dec 2019 06:54 - 12 Dec 2019 06:55
I like it. The only possible shortcoming I see is that the belt will have a little stretch in it. This might make really fine adjustment a little challenging, depending on how much friction is in the factory adjuster. If it is really smooth and has little friction, there may be no such problem at all. Nice out of the box thinking.
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
1981 KZ1000 LTD awaiting resurrection
2000 ZRX1100 not ridden enough
www.kzrider.com/11-projects/620336-anoth...uild-thread?start=24
Last edit: 12 Dec 2019 06:55 by TexasKZ.
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- TexasKZ
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Re: Mikuni RS34 carbs
12 Dec 2019 06:59 - 12 Dec 2019 07:04
Another possibility might be t adapt the flexible cable type adjuster used on the Keihin CVK carbs on the ZRX.
Number 16021 in the diagram.
www.partzilla.com/catalog/kawasaki/motor...zr1100-c4/carburetor
Number 16021 in the diagram.
www.partzilla.com/catalog/kawasaki/motor...zr1100-c4/carburetor
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
1981 KZ1000 LTD awaiting resurrection
2000 ZRX1100 not ridden enough
www.kzrider.com/11-projects/620336-anoth...uild-thread?start=24
Last edit: 12 Dec 2019 07:04 by TexasKZ.
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- baldy110
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Re: Mikuni RS34 carbs
12 Dec 2019 07:40
I don't understand why this is needed. Once warm the bike will idle normal so the low idle is only for a few minutes.
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Re: Mikuni RS34 carbs
12 Dec 2019 08:05 - 12 Dec 2019 08:11TexasKZ wrote: Another possibility might be t adapt the flexible cable type adjuster used on the Keihin CVK carbs on the ZRX.
Number 16021 in the diagram.
www.partzilla.com/catalog/kawasaki/motor...zr1100-c4/carburetor
Mikuni offers a flexible adjuster like that for the HSR. It would require modification to the threaded end, and may be difficult to adapt and use with the RS Series.
Rather than play around with that, I opted for this approach.
To compensate for minimal belt stretch, a washer can be placed behind the bracket...tried that while determining the best belt length to use.

1982 KZ1100-A2
Last edit: 12 Dec 2019 08:11 by daveo.
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Re: Mikuni RS34 carbs
12 Dec 2019 08:14baldy110 wrote: I don't understand why this is needed. Once warm the bike will idle normal so the low idle is only for a few minutes.
I wondered that too.

1982 KZ1100-A2
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- SWest
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Re: Mikuni RS34 carbs
12 Dec 2019 08:22
Sure would be nice to adjust the idle without reaching under the tank with a screwdriver. My 28's were easy sitting on the bike. Fine adjustments are a PITA. 
Steve

Steve
Z1b1000 1975 Z1b
kzrider.com/forum/11-projects/598262-kz-...-will-it-live#672882
kzrider.com/forum/2-engine/597654-poser?start=240#704229
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- daveo
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Re: Mikuni RS34 carbs
12 Dec 2019 09:47 - 12 Dec 2019 10:00SWest wrote: Sure would be nice to adjust the idle without reaching under the tank with a screwdriver. My 28's were easy sitting on the bike. Fine adjustments are a PITA.
Steve
I say amen to that ...
Three cheers for being lazy once in a while! :woohoo: :woohoo: :woohoo:
:whistle:
Time for a beer.
1982 KZ1100-A2
Last edit: 12 Dec 2019 10:00 by daveo.
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Re: Mikuni RS34 carbs
12 Dec 2019 10:16
I don't know why they did that unless being race carbs it would set them and GO. :woohoo:
Steve
Steve
Z1b1000 1975 Z1b
kzrider.com/forum/11-projects/598262-kz-...-will-it-live#672882
kzrider.com/forum/2-engine/597654-poser?start=240#704229
kzrider.com/forum/11-projects/598262-kz-...-will-it-live#672882
kzrider.com/forum/2-engine/597654-poser?start=240#704229
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- baldy110
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Re: Mikuni RS34 carbs
12 Dec 2019 15:08
I'm all about being lazy that's probably why I set my idle then don't ever touch it again.
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Re: Mikuni RS34 carbs
12 Dec 2019 20:52 - 13 Dec 2019 16:14baldy110 wrote: I'm all about being lazy that's probably why I set my idle then don't ever touch it again.
The special ordered M5-0.5 pitch socket cap screw fits too snug in the adjustment screw bracket, and does not turn smoothly like the original adjustment knob, so I'm packing it away for another day..
Far as tuning goes, I'm close but not quite there. Perhaps when Spring arrives I'll be able to get it right. Whatever new insights I can gain about the carbs between now and then will help.
These RS carbs have fine-tuning jetting and adjustment options that BS34's don't offer, and it's impressive how much better the engine responds with them.
One thing I don't understand well is the accelerator pump system. It currently is set to work from 1/4 to 3/4 slide opening. I believe Mikuni suggests that as a good starting point.


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Last edit: 13 Dec 2019 16:14 by daveo.
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- baldy110
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Re: Mikuni RS34 carbs
04 Jan 2020 18:59 - 04 Jan 2020 19:06
Put 300 miles riding and fine tuning the RS34's. The initial settings had the bike running great but since I'm anal retentive and all my shit must run perfectly, one of many character flaws I have I kept at it till it was perfect.
Final settings
20 pilot jets
Idle mixture screw 1/4 turn
Mains 125
Low speed air jet .08
Needle clip 4th from top
That gets me easy starts with choke, once warm idles nice, pulls hard no hickups anywhere with the spark plugs a nice peanut butter brown. The 17.5 pilots were just slightly lean and the 22.5 just slightly rich.
i lost my original motion pro mercury synching tool which I used for over 30 years. So for synching I first used the new motion pro tool with blue liquid, it really sucked. First you have to calibrate it then once hooked up and engine running the liquid takes a bit to settle down with every adjustment. I had to chase it around on every carb and couldnt get it fine tuned. I ended up getting a Morgan carbtune. That one is nice the columns are steady and adjustments are instant no need to wait a few seconda for the fluid column to settle down.
So now I'm finally done tuning the carbs and now will enjoy the bike.
Final settings
20 pilot jets
Idle mixture screw 1/4 turn
Mains 125
Low speed air jet .08
Needle clip 4th from top
That gets me easy starts with choke, once warm idles nice, pulls hard no hickups anywhere with the spark plugs a nice peanut butter brown. The 17.5 pilots were just slightly lean and the 22.5 just slightly rich.
i lost my original motion pro mercury synching tool which I used for over 30 years. So for synching I first used the new motion pro tool with blue liquid, it really sucked. First you have to calibrate it then once hooked up and engine running the liquid takes a bit to settle down with every adjustment. I had to chase it around on every carb and couldnt get it fine tuned. I ended up getting a Morgan carbtune. That one is nice the columns are steady and adjustments are instant no need to wait a few seconda for the fluid column to settle down.
So now I'm finally done tuning the carbs and now will enjoy the bike.

Last edit: 04 Jan 2020 19:06 by baldy110.
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- DoctoRot
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Re: Mikuni RS34 carbs
04 Jan 2020 23:57 - 04 Jan 2020 23:57
great bike. subtle mods. very nice
+1 on the morgan carbtune
+1 on the morgan carbtune
Last edit: 04 Jan 2020 23:57 by DoctoRot.
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