Parts diagram for Dellorto VHB carburetors

Detailed technical information regarding Dell’Orto motorcycle carburetors, how to tune, parts diagrams, slide specifications, needle specifications, jet specifications, and atomizer specifications.

Created: 2006 January 12

Updated: 2013 August 09

Thanks to Matt Cooper from Eurocarb for providing the following information describing the differences between the various VHB carbs.

VHB was the original carburetor for all 20 mm to 30 mm sizes. Then Dellorto changed to VHBZ for 20 mm to 26 mm carburetors and VHBT for 27 mm to 30 mm carburetors. VHBZ and VHBT have a separate needle and seat.

Table: Parts list for exploded parts diagram

Image Number	Part Number	Description	Sizes/options available
1	7447	Slide 20 mm - 26 mm	30, 40, 50, 60
1	7454	Slide 27 mm - 30 mm	60
2	2343	Needle 20 mm - 26 mm	E1 to E42
2	7455	Needle 27 mm - 30 mm	V1 to V14
3	8203	Atomizer U 20 mm - 26 mm	260
3	8299	Atomizer V 20 mm - 26 mm	260
3	8358	Atomizer K 20 mm - 26 mm	260, 262 ,264, 266, 268, 270
3	8566	Atomizer D 20 mm - 26 mm	260, 266, 270
3	7456	Atomizer M 27 mm - 30 mm	260, 262, 265, 270
3	7755	Atomizer N 27 mm - 30 mm	260, 265, 270
3	7790	Atomizer P 27 mm - 30 mm	260, 262, 265, 266, 268, 270
3	7972	Atomizer T 27 mm - 30 mm	260, 262, 264, 265, 266, 268, 270
3	7878	Atomizer 29 mm - 30 mm CS/CD	265, 270
4	6413	Main Jet	56 to 330, in steps of 1, 2, 3
5	1486	Idle jet (short)	30 to 198, in steps of 1, 2, 3
6	7746	Choke jet	45, 50, 55, 60, 65, 70, 75, 80, 85, 90
7	7450	Float Assembly	.1, .2, .3
8	1476	Rubber cable cap
9	1104	Cable adjuster
10	1691	Adjuster locknut
11	3978	Top cover screw, Hex Head
11	3318	Top cover screw
12	5011	Spring washer
13	7336	Top cover 20 mm - 26 mm
13	7338	Top cover 27 mm - 30 mm
14	8210	Top cover gasket 20 mm - 26 mm
14	8208	Top cover gasket 27 mm - 30 mm
15	7745	Choke support screw
16	8295	Choke support
17	8297	Choke support o-ring
18	3133	Choke return spring
19	3238	Choke piston
20	7449	Mixture screw
21	7446	Mixture screw spring
22	7673	Slide stop screw
23	4670	Slide stop spring
24	7448	Slide spring	2kg/35 mm
24	7941	Slide spring	1.1kg/35 mm
24	8750	Slide spring	0.8kg/35 mm
25	1407	Needle clip
26	8128	Clamp nut
27	8131	Manifold clamp 20 mm - 26 mm
27	8142	Manifold clamp 27 mm - 30 mm
28	8127	Clamp bolt
29	6976	Manifold sleeve 20 mm - 26 mm	I/D 28.57 mm
29	6977	Manifold sleeve 20 mm - 26 mm	I/D 28.57 mm (25 mm carb.)
29	7569	Manifold sleeve 20 mm - 26 mm	I/D 25.4 mm
29	8792	Manifold sleeve 20 mm - 26 mm	I/D 30 mm
29	7453	Manifold sleeve 27 mm - 30 mm	I/D 35 mm
29	8434	Manifold sleeve 27 mm - 30 mm	I/D 37 mm
30	6109	Fuel filter
31	9250	Fuel banjo	Plastic
32	4568	Banjo bolt
33	4559	Needle valve
33	9436	Needle valve assembly VHBZ/T
34	6173	O-ring
35	7346	Float pivot pin
36	7451	Float bowl o-ring
37	7335	Float bowl
38	6266	Float bowl seal
39	6267	float bowl nut
40	1481	Cable adjuster
41	1692	Adjuster locknut
42	3698	90 Degree cable elbow
42	3600	70 Degree cable elbow
42	9330	40 Degree cable elbow
42	10854	50 Degree cable elbow
43	8730	Pull-up choke assembly
44	9328	Choke locking spring
45	8294	Lever choke assembly 20 mm - 26 mm
45	8293	Lever choke assembly 27 mm - 30 mm
46	8260	Mixture screw washer
47	8678	Mixture screw o-ring
48	4650	Stop screw Washer
49	7540	Stop screw o-ring
50	5495	Circlip
51	9327	Choke operating lever
52	6288	Needle valve seal, VHBZ/T
53	4224	Trumpet, 20 mm
54	1439	Trumpet, 30 mm
55	3100	Trumpet
56	7878	Atomizer, VHB CS/CD
57	4052	Banjo bolt seal
59	6517	Fuel banjo
60	8752	Fuel banjo, 6 mm
61	4053	Banjo bolt
62	7890	Double fuel banjo
63	7879	Pump body
64	7831	Pump piston
65	7185	Pump ball bearing
66	7832	Holder
67	7882	Spring	Pump assembly for CS/CD
68	7828	Main jet holder
69	1486	Main jet (See item 5 for sizes)
70	4057	Float bowl seal
71	7880	Float bowl nut
72	52510	Gasket set	VHB/T 29 mm - 30 mm C
72	52511	Gasket set	VHB Linked
72	52512	Gasket set	VHB/Z 20 mm - 26 mm
72	52517	Gasket set	VHB/T 27 mm - 30 mm
72	52517	Gasket set	VHB/T 27 mm - 30 mm