Mikuni 29mm jetting help
- cam9281
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Mikuni 29mm jetting help
05 Apr 2020 07:22
Hello all,
I have a 1977 kz1000 LTD. It has the 1100 kit on it with heavy duty valve springs. Dyna ignition and coils. It has a stock airbox and the stock exhaust with some of the baffles removed. I am looking to put a set of 29mm mikuni carbs on it. My question is, what should my pilot and main jet size be? And what should the air screws be set at? Any information will be greatly appreciated.
I have a 1977 kz1000 LTD. It has the 1100 kit on it with heavy duty valve springs. Dyna ignition and coils. It has a stock airbox and the stock exhaust with some of the baffles removed. I am looking to put a set of 29mm mikuni carbs on it. My question is, what should my pilot and main jet size be? And what should the air screws be set at? Any information will be greatly appreciated.
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- kevski
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Re: Mikuni 29mm jetting help
06 Apr 2020 07:52 - 06 Apr 2020 07:52
Start with stock jetting, air screw 1 and 1/8 turns out, come up on the mains one size at a time possibly one size on the pilot jet, short of putting it on a dyno this is how you have to go, make sure valve lash is correct and timing all set prior to carb work as well.
Last edit: 06 Apr 2020 07:52 by kevski.
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- Dr. Gamma
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Re: Mikuni 29mm jetting help
06 Apr 2020 13:43 - 06 Apr 2020 13:45
Went back through some of my old notes on 29mm Smoothbores on a stock Kz1000 motor.
I am coming up with 25 pilot, 117.5 or 120 mains, and anywhere from 3/4 to 1 1/8 turns out on air screw. These specs are with either velocity stacks or Unifilter individual filters with a 4 into 1 pipe.
Never did a 1000 motor with 29's., a stock air box, and stock pipes. You might have to go down to a 115 main if the 117.5's or the 120 mains are too rich!!!!
At least throw that rear silencer that mounts up to the rest of the air box away too. That thing is worthless. We used to throw them away on box stock bikes back in the day!!!!
I am coming up with 25 pilot, 117.5 or 120 mains, and anywhere from 3/4 to 1 1/8 turns out on air screw. These specs are with either velocity stacks or Unifilter individual filters with a 4 into 1 pipe.
Never did a 1000 motor with 29's., a stock air box, and stock pipes. You might have to go down to a 115 main if the 117.5's or the 120 mains are too rich!!!!
At least throw that rear silencer that mounts up to the rest of the air box away too. That thing is worthless. We used to throw them away on box stock bikes back in the day!!!!
1972 H2 750 Cafe Racer built in 1974.
1976 KH400 Production Road Racer.
1979 Kz1000 MK. II Old AMA/WERA Superbike.
1986 RG500G 2 stroke terror.
1986 GSXR750RG The one with the clutch that rattles!
Up in the hills near Prescott, Az.
1976 KH400 Production Road Racer.
1979 Kz1000 MK. II Old AMA/WERA Superbike.
1986 RG500G 2 stroke terror.
1986 GSXR750RG The one with the clutch that rattles!
Up in the hills near Prescott, Az.
Last edit: 06 Apr 2020 13:45 by Dr. Gamma.
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- Mikaw
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Re: Mikuni 29mm jetting help
06 Apr 2020 18:53
1976 KZ 900 A4
kzrider.com/forum/11-projects/613548-1976-kz-900-a4
1976 KZ 900 B1 LTD
1978 KZ 1000 B2 LTD
1980 KZ 750 E1
Kowledge Speaks, But Wisdom Listens.
Jimi Hendrix.
1976 KZ 900 B1 LTD
1978 KZ 1000 B2 LTD
1980 KZ 750 E1
Kowledge Speaks, But Wisdom Listens.
Jimi Hendrix.
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- Mikaw
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Re: Mikuni 29mm jetting help
06 Apr 2020 18:56
If you search bing or goggle with “29mm mikuni KZR” you find lots of data. You pick what works for you.
1976 KZ 900 A4
kzrider.com/forum/11-projects/613548-1976-kz-900-a4
1976 KZ 900 B1 LTD
1978 KZ 1000 B2 LTD
1980 KZ 750 E1
Kowledge Speaks, But Wisdom Listens.
Jimi Hendrix.
1976 KZ 900 B1 LTD
1978 KZ 1000 B2 LTD
1980 KZ 750 E1
Kowledge Speaks, But Wisdom Listens.
Jimi Hendrix.
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- DOHC
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Re: Mikuni 29mm jetting help
06 Apr 2020 20:07
Sudco has a carb tuning manual. I have the 5th edition. They provide a table with a recommended starting point for VM29s in different applications. I'm assuming these will tend to be on the rich side, but it's a good reference.
'78 Z1-R in blue
, '78 Z1-R in black,
'78 Z1-R in pieces
My dad's '74 Z1
'00 ZRX1100
My dad's '74 Z1
'00 ZRX1100
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- kevski
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Re: Mikuni 29mm jetting help
07 Apr 2020 01:33
I meant to ask original poster if he has 29mm smooth-bores or stock 28s which measure 29 at mouth opening but 28 in the throat at the slide, it's a common mistake as most of us know, maybe a couple of pictures will assist.
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