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Jet Needles / Main Jets / Gas Mileage
- WABBMW
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- Let The Good Times Roll !
I used washers to raise the jet needles by 4 mm., and increased the Main jets by two sizes. Now the bike runs really strong, but the gas mileage dropped to about 43 MPG.
From what I read, if I go very easy on the throttle, (never open more than 1/4), then the Main jets should not affect gas mileage. Is this true?
I expect that I may have gone a little too far on raising the jet needles. Does anybody know the spacing between the grooves on adjustable jet needles? How many grooves does the 4 mm. equate to? Please advise. Thanks.
Bill Baker
Houston, Texas
1982 KZ650 CSR
2008 Yamaha FZ1
2006 Yamaha FZ1
1977 Honda Supersport 750 four (sold)
1984 Honda Nighthawk 650 (sold)
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- Skyman
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- 1978 KZ1000-B2 LTD 1982 KZ1000-M2 CSR
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West Linn, OR
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- Motor Head
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- FIX UP YOUR BIKE RIGHT AND CHEAP
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Sounds like you are masking over another problem, such as vacuum leaks or possibly a low float level, leaking slide diaphragm, or some PO has done some drilling on the air bleeds or changed gets/ needle to something leaner.
1982 KZ1000LTD K2 Vance & Hines 4-1 ACCEL COILS Added Vetter fairing & Bags. FOX Racing rear Shocks, Braced Swing-arm, Fork Brace, Progressive Fork Springs RT Gold Emulators, APE Valve Springs, 1166 Big Bore kit, RS34's, GPZ cams.
1980 KZ550LTD C1 Stock SOLD Miss it
1979 MAZDA RX7 in the works, 13B...
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- Patton
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- KZr Legend
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i.d. .106
o.d. .250
thickness .020 (.5mm)
Seem to remember reading somewhere that 2 shims equals one clip position, which is consistent with Skyman's recollection of 1mm between clip positions.
Good Fortune!
1973 Z1
KZ900 LTD
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- otakar
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74 Z1-A stock
76 KZ-900 Totaly stock vice MAC pipe
77 KZ-1000A stock
78 Z1-R 100%MINT 500 original Mi.
78 Z1-R Yoshi 1103 kit stage 1 cams Yoshi pipe. Etc
79 KZ-1300 (1400)
80 KZ-1300
81 Scratch built GPz1150R
82 KZ1000
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- bountyhunter
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On mine the grooves are about .030" apart. I think that is 0.75mm?I expect that I may have gone a little too far on raising the jet needles. Does anybody know the spacing between the grooves on adjustable jet needles? How many grooves does the 4 mm. equate to? Please advise. Thanks.
1979 KZ-750 Twin
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- Becker
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- The Doctor Will Rise Again
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78 KZ750B3
79 KZ400 LTD
78 KZ650C2
79 KZ650C3
78 KZ650B2A
80 KZ650F1
80 KZ650E1
81 CB750K Super Sport
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- Patton
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...On mine the grooves are about .030" apart. I think that is 0.75mm?
NO FAIR measuring! :laugh: :laugh:
1973 Z1
KZ900 LTD
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- WABBMW
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- Let The Good Times Roll !
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I'll provide feedback as to how it works out. Thanks everybody.
Bill Baker
Houston, Texas
1982 KZ650 CSR
2008 Yamaha FZ1
2006 Yamaha FZ1
1977 Honda Supersport 750 four (sold)
1984 Honda Nighthawk 650 (sold)
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- Kawickrice
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- After Monday & Tuesday, even the calendar says WTF
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73 Kawasaki Z1
07 HD CVO Ultra Classic
82 Suzuki GS 1100
74 Yamaha RD 350 (My two stroke toy)
77 Kawasaki KZ 650B-1 (My putt around bike)
80 Indian Moped (My American Iron)
1
Long Gone
75 Suzuki GT550
74 GT 380
79 RD 400 Daytona Special
72 Honda CL 175
74 Honda QA 50
Tampa FL
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- otakar
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74 Z1-A stock
76 KZ-900 Totaly stock vice MAC pipe
77 KZ-1000A stock
78 Z1-R 100%MINT 500 original Mi.
78 Z1-R Yoshi 1103 kit stage 1 cams Yoshi pipe. Etc
79 KZ-1300 (1400)
80 KZ-1300
81 Scratch built GPz1150R
82 KZ1000
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- bountyhunter
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Center to center across the slots. I used dig calipers across five slots measuring from the top edge of the upper and lower slot, then divided by four. I think that's the right value, but my eyes are not as young as they used to be. I couldn't bet my life that it's not 1mm.Is the .75mm reading center to center or just the thickness of material between the slots??
1979 KZ-750 Twin
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