Contents
carburetor years Honda model
09. Z50A 0-0 ’68-69 Z50A K0
09. Z502 0-0 ’69-71 Z50A K1-K2
10. 655-A 00 ’72-75 Z50A K3-K6
10. 674-A 00 ’70-75 QA50 K0-K3
11. PA03A-A ’76-78 Z50A K7-K9
11. PA03C-A ’79-81 Z50R
11. PA03D-A ’82-85 Z50R
11. PA03F-B ’86-87 Z50R
12. PA03H-A ’88-88 Z50R
12. PA03H-B ’88-91 Z50R
12. PA03M-A ’92-93 Z50R
12. PA03N-A ’94-99 Z50R
13. PA42A-C ’00-03 XR50R
13. PA???? ’04-09 CRF50F
9. Keihin
# carb code frame# range 00 US models
a Z50A 045 up to Z50A-255950 ’68-69 Z50A K0
b Z502 045 after Z50A-255950 ’69-70 Z50A K1
b Z502 045 after Z50A-255950 ’70-71 Z50A K2
1. Keihin Z50A, Z502 on 1968-71 Z50A
2. 1968-71 Z50A carb kit
Flange Mount: 32mm hole spacing, 2 x 18 (22 od) o-ring
Main Jet: This carb has a screw-in main jet size 50.
Pilot Jet: It also has a screw-in idle (pilot) jet size 38.
Float Seat: It also has a screw-in float needle seat, replaceable.
Float: no-stirrup metal-tip needle valve, metal swinging float
The Z50A and Z502 carbs are the same except for the needle jet #12 and rubber cable pipe #10.
o# ab price Honda part# carburetor
o9 10 N/A 16100-045-670 Z50A ’68-69 Z50A up to 255950
o9 01 N/A 16100-045-671 Z502 ’69-71 Z50A after 255950
o# ab price Honda part# parts list
26 11 N/A 99101-050-004 main jet 50
10. Keihin
# carb code US models
a 655-A 130 ’72-75 Z50A K3-K6
b 674-A 114 ’70-72 QA50 K0
b 674-A 129 ’73-75 QA50 K1-K3
1. Keihin 655-A on 1972-75 Z50A
2. 1974-75 Z50A carb kit, missing the drain plug o-ring and jet pad disk.
3. 1970-73 Z50A carb kit also had a float seat and a float seat washer.
3. 16010-114-004 gasket set
4. 16015-114-004 drain screw for 1970-73 Z50A
Flange Mount: 32mm hole spacing, no o-ring groove on carburetor. Instead the o-ring groove is on the intake manifold. Since the 2 x 18 (22 od) intake o-ring is not part of the carburetor, it is not in the Honda gasket set 16010-114-004, or the multi-app set 16010-114-305.
Main Jet: This carb has a “long” press-in jet, with a rubber pad disk under it.
Pilot Jet: The idle jet is not replaceable. It is inside the upper end of the brass tube, pressed into the main body, on the engine side of the main jet.
Float Seat early: The 1970-73 carburetor had a screw-in float needle seat, that was replaceable, like in the illustration.
Float Seat late: The 1974-75 carburetor did not have a replaceable float needle valve seat. The seat was part of the main body, and must be cleaned and polished with a spinning Q-tip.
Float: no-stirrup metal-tip needle valve, swinging float 16013-114-004
Top Cap: M18 x 1.0 thread
Drain screw: 1970-73 chamber set 16015-114-004 had a M4-0.7 thread drain screw with a 2 x 4 (8 od) o-ring. 1974-75 had a M6-0.75 thread drain screw with no o-ring. 1976-78 had a M6-1.0 thread drain screw with a 2 x 2.5 (6.5od) o-ring. 1979-later had a 1.5 x 4 (7od) drain screw o-ring.
o# abcd price Honda part# carburetor
o9 1000 N/A 16100-120-010 655-A ’72-73 Z50A
o9 0100 N/A 16100-120-010 655-A ’74-75 Z50A
o9 0010 N/A 16100-114-014 674-A K ’70-71 QA50 K0 to 1057061
o9 0001 N/A 16100-114-024 674-A-K1 ’71-72 QA50 K0 1057062-on
o9 0001 N/A 16100-129-000 674-A K1 ’73-75 QA50 K1 K2 K3
o# abcd price Honda part# parts list
o1 1111 $24 16010-114-004 gasket solo set d e h n p r
o1 0000 N/A 16010-114-305 gasket multi set d e h n p r q
1.1 1111 $14 16197-063-004 e jet support disk Ø7.3 x 1.75
1.2 1111 $$2 00000-000-000 h intake o-ring 2 x 18 (22 od)
1.3 1111 0$2 16176-551-004 d main jet o-ring 1 x 3 (5 od)
1.4 1111 0$5 16174-045-004 r drain screw o-ring 2 x 4 (8od)
1.5 1111 0$5 16171-044-004 p top rubber washer 10 x 15 x 1
1.6 1111 0$3 16173-063-004 n float o-ring 1.5 x 40 (43 od)
02 1111 N/A 16011-045-004 float valve set
03 1100 N/A 16012-120-004 jet needle set
03 0011 N/A 16012-114-004 jet needle set
04 1111 N/A 16013-114-004 float set
05 1111 N/A 16014-120-004 top set
06 1111 N/A 16015-114-004 float chamber set
07 1111 N/A 16016-045-610
07 1111 N/A 16016-063-004 adjustment screw set
7a 1111 N/A 16162-044-004 idle air screw
7b 1111 N/A 16181-001-004
7b 1111 N/A 16181-250-004 idle air spring
7c 1111 N/A 16163-063-004 idle speed screw
7d 1111 N/A 16185-044-004 idle speed spring
08 1100 N/A 16022-120-004
08 1100 N/A 16022-120-305 throttle valve-spring set
8a 1100 N/A 16111-120-004
8a 1100 N/A 16111-120-305 throttle valve
8b 1100 N/A 00000-000-000 throttle spring
08 0010 N/A 16022-063-004 throttle valve-spring set
08 0001 N/A 16022-129-004 throttle valve-spring set
10 0010 N/A 16194-045-004
10 1111 N/A 16194-045-770 rubber cap
11 1111 N/A 93500-030-050 cross screw 3 x 5 choke
12 2222 $$1 93500-040-120 pan screw 4 x 12 float
13 1111 .50 0-94111-03000 spring washer 3 choke lever
14 2222 .50 0-94111-04000 spring washer 4 float bowl
o# abcd price Honda part# long push-in jets
15 1000 N/A 99201-114-520 jet 52 ’72-73 Z50A K3 to K4
15 0100 N/A 99201-114-550 jet 55 ’74-75 Z50A K5 to K6
15 0010 N/A 99201-114-480 jet 48 ’70-73 QA50 K0 to 1057061
15 0001 N/A 99201-114-520 jet 52 ’70-75 QA50 K0 105762-on to K3
11. Keihin
# carb 00 size code US models
a PA03A-A 10 130 ’76-78 Z50A K7-K9
b PA03B-A 11 130 79-’79 Z50A K9 up to 5022291
c PA03C-A 11 181 ’80-81 Z50R A,B after 5022291
d PA03D-A 11 181 ’82-85 Z50R C,D,E,F
e PA03F-B 11 181 ’86-87 Z50R G,H
In 1979 the model name changed from Z50A to Z50R, and the name Mini Trail was dropped.
1. 16100-130-642 Keihin PA 03A-A for 1976-78 Z50A from cmsnl.com
2. 16100-165-004 Keihin PA 03B-A for 1979 Z50R
3. 16100-165-014 Keihin PA 03C-A for 1979-81 Z50R from cmsnl.com
4. 16100-181-751 Keihin PA 03D-A for 1982-85 Z50R
1. 16010-181-832 Keihin PA 03F-B for ’86-87 Z50R from cmsnl.com
2. 1976-78 Z50A carb kit D348 thick needle, #58 push-in jet. The drain screw and jet support pad are missing.
3. 1979-81 Z50R carb kit D117 thin needle, #58 screw-in jet. Left to right: drain screw, needle jet (emulsion tube), idle air screw, idle speed screw, float needle
Flange Mount: 38 mm hole spacing 1976-78. 32 mm hole spacing 1979-87.
Pilot Jet: The idle jet is not replaceable. It is inside the upper end of the brass tube, pressed into the main body, on the engine side of the main jet.
Main Jet: For some reason in 1979 Honda wanted to make their jets tamper-proof. It’s funny that they went from one extreme to the other, from jets that fall out too easy, to jets that never come out. Both the NC50 and the Z50 changed to “fixed” jets (not replaceable) in late 1978 and 1979. After 1981 the jet was a screw-in, thankfully, like in the illustration
Float Seat: This carb does not have a replaceable float needle valve seat. The seat is part of the main body, and must be cleaned and polished with a spinning Q-tip.
Carb Kit: Beware of low-cost carburetor kits. In the kit at the right several things are wrong or made badly. 1) it is missing the press-in jet pad disk, 2) the jet o-ring was too big to allow the jet to press in. You can see it seems big in the photo. It was size 1.5 x 4 instead of 1 x 3, 3) the float needle was longer than stock, and the wire stirrup was bent badly in two ways. The throttle (jet) needle was D117 thin instead of D348 thick.
Float: In 1979 the float and float needle changed, from stirrup-type needle valve with black foam float, to no-stirrup needle valve 16155-883-005 with white plastic float 16013-147-004. Like before, the float needle has a rubber cone upper tip and a spring-loaded lower tip.
Float Bowl: The 1979-later float bowl no longer has a press-in jet support pad disk 7.5 x 1.8mm.
1. 16010-081-004, 2. 16010-081-014
3. 16010-165-621, 4. 16010-181-305
US models are blue .
abc de f gh price Honda part# ∅10 x 38 carbs
10000 000 N/A 16100-130-641
10000 000 N/A 16100-130-642 PA03A-A ’76-78 Z50A
abc de f gh price Honda part# ∅10 x 32 carbs
00000 100 N/A 16100-165-731 PA000-0 ‘Xx Z50GZ Gorilla DE 731 slide, 731 needle, smaller jet?
abc de f gh price Honda part# ∅11 x 32 long cable pipe
01000 000 N/A 16100-165-004 PA03B-A ’79-79 Z50R
00100 000 N/A 16100-165-014 PA03C-A ’79-79 Z50R long cable pipe
00100 000 N/A 16100-165-014 PA03C-A ’79 Z50G Monkey
00100 000 N/A 16100-165-014 PA03C-A ’79 Z50J Monkey AU,
00100 000 N/A 16100-165-014 PA03C-A ’92 Z50J Monkey FI, ??
00100 000 N/A 16100-165-014 PA03C-A ‘Xx Z50JZ Monkey Sweden
00100 000 N/A 16100-165-014 PA03C-A ‘Xx Z50GZ Gorilla Exp, AU, SA
00100 000 N/A 16100-165-305 PA03C-B ’80-81 Z50R
00010 000 N/A 16100-181-751 PA03D-A ’82-85 Z50R
00001 000 N/A 16100-181-830
00001 000 N/A 16100-181-831
00001 000 N/A 16100-181-832 PA03F-B ’86-87 Z50R
abc de f gh price Honda part# ∅11 x 32 short cable pipe
00000 010 N/A 16100-165-950 PA000-0 ’92 Z50J Monkey FI up to AB02E6302452
00000 010 N/A 16100-165-951 PA000-0 ’92 Z50J Monkey FI from AB02E6302453
00000 010 N/A 16100-165-951 PA000-0 ’96 Z50J Monkey FI shorter cable pipe
00000 010 N/A 16100-165-306
00000 001 N/A 16100-165-A11 .
abc de f gh price Honda part# ∅11 x 32 round float bowl
00000 001 N/A 16100-165-A12 PA000-0 ‘Xx Z50J1 Gorilla Japan round bowl
o# abc de f gh price Honda part# gaskets
o1 10000 000 $35 16010-081-004 gasket solo-set 1a o d s f o h i
o1 01100 100 $25 16010-081-014 gasket solo-set 1a o o o f g h
o1 00011 000 $30 16010-181-831 gasket solo-set oo o o o f g h o l
o1 01111 100 $32 16010-181-305 gasket multi-set 1a o o o f g h o l
o1 00000 010 $30 16010-165-981 gasket solo-set 1a 0 d 0 f g h
o1 11100 110 $37 16010-143-305 gasket multi-set 1a c d s f g h i
o1 000000001 N/A 16010-165-A11 gasket solo-set 1b c 0 0 . g 0 . . m
1a 10000 110 $$3 00000-000-000 top rubber washer 10 x 18 x 1
1b 00000 001 $$8 00000-000-000 top rubber washer 13 x 16.5 x 1
1c 00000 001 $$2 00000-000-000 intake o-ring 2 x 20 (24 od)
1d 10000 010 0$2 16176-551-004 jet o-ring 1 x 3 (5 od)
1f 11111 110 $18 00000-000-000 float gasket Ø1.5 NC50-type
1g 01111 111 $$2 00000-000-000 drain o-ring 1.5 x 4 (7 od)
1h 11011 110 $$2 00000-000-000 intake o-ring 2 x 18 (22 od)
1i 10000 000 0$2 16175-260-004 drain o-ring 2 x 2.5 (6.5 od)
1l 01111 000 0$4 16110-181-831 top rubber washer 13 x 19 x 1
1m00000 001 N/A 00000-000-000 float bowl o-ring 2.0 x 49
1s 10000 000 $14 00000-000-000 jet pad disk Ø7.5 x 1.8
o# abcde f gh price Honda part# parts list
02 10000 000 N/A 16012-130-640 needle set 03AA
o2 01000 000 N/A 16012-165-014 needle set 03BA
o2 00111 000 N/A 16012-181-831 needle set 03CA, 03DA, 03FB
o3 10000 000 N/A 16013-099-691
o3 10000 000 $46 16013-143-620 float set 3a oo 3c 3d black stirrup
o3 01111 000 $28 16013-147-004 float set oo 3b 3c 3d white regular
3a 10000 000 N/A 00000-000-000 float bare, solid black foam stirrup
3b 01111 000 $21 00000-000-000 float bare hollow white plastic regular
3c 11111 000 $$4 00000-000-000 hinge pin substitute Ø2 x 18.5
3d 11111 000 $$3 0-93600-04006 hinge screw M4x6 sunk phillips
o4 11100 000 N/A 16014-130-640 top set with pipe 4a 1a M18-1.0
o4 00011 000 N/A 16014-GB1-912 top set with pipe 4a 1l M20-1.0
o5 10000 000 N/A 16015-130-640 chamber set 5a 1e 1f 5b 1g
o5 01000 000 N/A 16015-099-691 chamber set 5a oo 1f 5b 1g
o5 00111 000 N/A 16015-130-641
05 00111 000 N/A 16015-165-621 chamber set 5a oo 1f 5b 1g
o6 11000 000 N/A 16016-143-620 screw set
o6 00111 000 N/A 16016-165-004 screw set
6a 00111 000 N/A 16016-165-621
6a 00111 000 N/A 16016-165-505 screw set A (idle air)
6b 00001 000 N/A 16208-GC8-004 screw set B (idle speed)
o7 11000 000 N/A 16022-081-004
o7 11000 000 N/A 16022-HB2-003 slide set
o7 00111 000 N/A 16022-165-004
o7 00111 000 N/A 16022-GW8-671
o7 00111 000 N/A 16022-GW8-672 slide set
o9 11110 000 N/A 16118-121-014 rubber cable pipe cover
10 10000 000 N/A 16011-143-620
10 10000 000 N/A 16011-881-741 float needle valve stirrup
10 01111 000 $22 16155-883-005 float needle valve regular
11 22222 000 0$1 93892-04012-08 screw & washer M4x12 pan phillips
o# abc de f gh price Honda part# jets
14 10000 000 $16 99201-081-0580 main jet push-in #58 0.0228″
14 01100 000 N/A fixed needle jet and main jet pressed in 0.0228″
14 00011 000 0$7 99101-187-0580 main jet screw-in #58 0.0228″
18 11111 000 N/A (not sold separately) idle jet press-in tube 0.015″ pinhole
12. Keihin
# carb 000 code Honda US model
a PA 03H-A GW8 88–’88 Z50R up to JS900485
b PA 03H-B GW8 ’88-91 Z50R after JS900485
c PA 03M-A GW8 ’92-93 Z50R
d PA 03N-A GW8 ’94-99 Z50R
e PA 42A-C GW8 ’00-03 XR50R
a PA 42A-C GEL ’04-05 CRF50F
f PA 42??? GEL ’06-06 CRF50F
1. 16100-GW8-682 Keihin PA 03M-A
2. 16100-GW8-305 Keihin PA 03N-A from cmsnl.com
3. 16100-GEL-702 Keihin PA 42A-C
4. CRF50F carb. The gasket for this was in use for over 34 years!
In 2000 the Z50R was replaced by the XR50R. The PA03N-A carburetor became PA42A-C, but only the needle jet and the idle air screw changed.
In 2004 the XR50R was replaced by the CRF50F. The PA42A-C carburetor did not change until 2006.
2006 was the last year of CRF50F in the US, but in Europe it continued up to 2011.
Flange Mount: 32mm hole spacing
Main Jet: screw-in #58, M6-0.75
Float: no-stirrup type white plastic 16013-147-004, needle valve 16155-883-005
Top Cap: M20-1.0 thread
Idle Mixture Screw: For the entire Z50A, Z50R, XR50R, CRF50F year range 1968 to 2006, the idle mixture screw was an air type, not a fuel type. An idle air screw blocks an air tunnel, so tighter is less air (richer). An idle fuel screw blocks off a fuel tunnel, so tighter is less fuel (leaner).
1. 1992-98 Z59R carb kit, 2. 16010-181-831 for PA 03H 03M 03N
3. 16010-181-305 gasket set for PA 03H 03M 03N
4. 16016-GW8-672 This idle air screw looks like an idle fuel screw.
o# abcde f price Honda part# carburetor
o8 100000 N/A 16100-GW8-671
o8 100000 N/A 16100-GW8-672 PA 03H-A 1988 Z50R up to JS900485
o8 010000 N/A 16100-GW8-673 PA 03H-B ’88-91 Z50R mix screw changed
o8 001000 N/A 16100-GW8-680
o8 001000 N/A 16100-GW8-681
o8 001000 N/A 16100-GW8-682 PA 03M-A ’92-93 Z50R
o8 001000 N/A 16100-GW8-780
o8 001000 N/A 16100-GW8-791
o8 000100 N/A 16100-GW8-792 PA 03N-A ’94-99 Z50R
o8 111100 N/A 16100-GW8-305 PA 03N-A replacement
o8 000010 N/A 16100-GEL-701
o8 000010 N/A 16100-GEL-702 PA42A-C ’00-05 XR50R, CRF50F
o8 000001 N/A 16100-GEL-A21 PA42??? ’06 CRF50F
o# abcde f price Honda part# gaskets
o1 111111 $32 16010-181-831 gasket solo-set o0 1f 1g 1h 1l
o1 111111 $32 16010-181-305 gasket multi-set 1a 1f 1g 1h 1l
1f 111111 $18 00000-000-000 float bowl gasket Ø1.5 NC50-type
1g 111111 $$2 00000-000-000 drain plug o-ring 1.5 x 4 (7 od)
1h 111111 $$2 00000-000-000 intake o-ring 2 x 18 (22 od)
1l 111111 0$4 16110-181-831 top rubber washer 13 x 19 x 1
o# abcde f price Honda part# parts list
02 110000 N/A 16012-GW8-671 needle set
02 001100 N/A 16012-GW8-680 needle set
02 000010 N/A 16012-GEL-701 needle set
02 000001 N/A 16012-GEL-A21 needle set
03 111111 $28 16013-147-004 float set oo 3b 3c 3d
04 111111 N/A 16015-099-691 chamber set
05 100000 N/A 16016-GW8-671
05 111100 N/A 16016-GW8-672 screw set idle air
05 000011 N/A 16016-GEL-701 screw set idle air
06 111110 N/A 16022-GW8-671
06 111111 N/A 16022-GW8-672 slide set
07 111111 N/A 16028-GC8-004 idle speed screw set
09 111111 N/A 16014-181-831 top set M20-1.0 thread
10 111111 $22 16155-883-005 float needle valve
11 222222 0$1 93892-04012-08 screw & washer M4x12 pan phillips
14 110000 N/A 99101-187-0550 main jet screw-in #55
14 001111 0$7 99101-187-0580 main jet screw-in #58
Service: Here is a good article about how to remove and clean the non-replaceable idle (pilot) jet.
https://thumpertalk.com/forums/topic/1047667-clogged-pilot-jet-on-a-crf50-success/
The CRF50F idle jet in that article did not crush when gripped lightly with a vise grip pliers. But some pressed-in idle jets have thin walls, or have a tighter fit that needs heavy clamping. Those require a close-fitting drill bit or solid wire, be placed in the hole first, to prevent crushing the tube with the vise grips. It’s a good idea to do that always.