Tables / 20B

Sprocket chart 1 1/4" x 3/4" — 20B

Chain European ISO 606 / DIN 8187 · pitch 1.250" (31.75 mm) · roller Ø 0.750" · inner width 0.770" · simplex tooth width 0.732". Dimensions in inches. Tap a row to open it in the calculator (duplex, triplex, mm, material).

N	PD	OD	BD	CD	Max hub
8	3.266	3.713	2.516	2.516	1.906
9	3.655	4.120	2.905	2.849	2.323
10	4.045	4.524	3.295	3.295	2.735
11	4.437	4.928	3.687	3.642	3.145
12	4.830	5.331	4.080	4.080	3.553
13	5.223	5.733	4.473	4.435	3.960
14	5.617	6.134	4.867	4.867	4.365
15	6.012	6.535	5.262	5.229	4.769
16	6.407	6.935	5.657	5.657	5.172
17	6.803	7.336	6.053	6.024	5.575
18	7.198	7.736	6.448	6.448	5.977
19	7.594	8.135	6.844	6.818	6.379
20	7.991	8.535	7.241	7.241	6.781
21	8.387	8.934	7.637	7.613	7.182
22	8.783	9.334	8.033	8.033	7.582
23	9.180	9.733	8.430	8.409	7.983
24	9.577	10.132	8.827	8.827	8.383
25	9.973	10.531	9.223	9.204	8.783
26	10.370	10.930	9.620	9.620	9.183
27	10.767	11.328	10.017	9.999	9.583
28	11.164	11.727	10.414	10.414	9.982
29	11.561	12.126	10.811	10.794	10.382
30	11.958	12.525	11.208	11.208	10.781
31	12.356	12.923	11.606	11.590	11.181
32	12.753	13.322	12.003	12.003	11.580
33	13.150	13.720	12.400	12.385	11.979
34	13.547	14.119	12.797	12.797	12.378
35	13.945	14.517	13.195	13.181	12.777
36	14.342	14.915	13.592	13.592	13.176
37	14.740	15.314	13.990	13.976	13.575
38	15.137	15.712	14.387	14.387	13.974
39	15.534	16.110	14.784	14.772	14.372
40	15.932	16.509	15.182	15.182	14.771
41	16.329	16.907	15.579	15.567	15.170
42	16.727	17.305	15.977	15.977	15.568
43	17.124	17.704	16.374	16.363	15.967
44	17.522	18.102	16.772	16.772	16.366
45	17.919	18.500	17.169	17.159	16.764
46	18.317	18.898	17.567	17.567	17.163
47	18.715	19.296	17.965	17.954	17.561
48	19.112	19.695	18.362	18.362	17.960
49	19.510	20.093	18.760	18.750	18.358
50	19.907	20.491	19.157	19.157	18.756
51	20.305	20.889	19.555	19.545	19.155
52	20.703	21.287	19.953	19.953	19.553
53	21.100	21.685	20.350	20.341	19.952
54	21.498	22.083	20.748	20.748	20.350
55	21.896	22.481	21.146	21.137	20.748
56	22.293	22.880	21.543	21.543	21.147
57	22.691	23.278	21.941	21.932	21.545
58	23.089	23.676	22.339	22.339	21.943
59	23.486	24.074	22.736	22.728	22.341
60	23.884	24.472	23.134	23.134	22.740
61	24.282	24.870	23.532	23.524	23.138
62	24.680	25.268	23.930	23.930	23.536
63	25.077	25.666	24.327	24.320	23.934
64	25.475	26.064	24.725	24.725	24.333
65	25.873	26.462	25.123	25.115	24.731
66	26.270	26.860	25.520	25.520	25.129
67	26.668	27.258	25.918	25.911	25.527
68	27.066	27.656	26.316	26.316	25.925
69	27.464	28.054	26.714	26.707	26.324
70	27.861	28.452	27.111	27.111	26.722
71	28.259	28.850	27.509	27.502	27.120
72	28.657	29.248	27.907	27.907	27.518
73	29.055	29.646	28.305	28.298	27.916
74	29.453	30.044	28.703	28.703	28.314
75	29.850	30.442	29.100	29.094	28.712
76	30.248	30.840	29.498	29.498	29.111
77	30.646	31.238	29.896	29.889	29.509
78	31.044	31.636	30.294	30.294	29.907
79	31.441	32.034	30.691	30.685	30.305
80	31.839	32.432	31.089	31.089	30.703
81	32.237	32.830	31.487	31.481	31.101
82	32.635	33.228	31.885	31.885	31.499
83	33.033	33.626	32.283	32.277	31.897
84	33.430	34.024	32.680	32.680	32.295
85	33.828	34.422	33.078	33.072	32.693
86	34.226	34.820	33.476	33.476	33.091
87	34.624	35.218	33.874	33.868	33.489
88	35.022	35.616	34.272	34.272	33.888
89	35.419	36.014	34.669	34.664	34.286
90	35.817	36.412	35.067	35.067	34.684
91	36.215	36.810	35.465	35.460	35.082
92	36.613	37.208	35.863	35.863	35.480
93	37.011	37.606	36.261	36.255	35.878
94	37.408	38.004	36.658	36.658	36.276
95	37.806	38.402	37.056	37.051	36.674
96	38.204	38.800	37.454	37.454	37.072
97	38.602	39.198	37.852	37.847	37.470
98	39.000	39.596	38.250	38.250	37.868
99	39.397	39.994	38.647	38.643	38.266
100	39.795	40.392	39.045	39.045	38.664
101	40.193	40.790	39.443	39.438	39.062
102	40.591	41.188	39.841	39.841	39.460
103	40.989	41.586	40.239	40.234	39.858
104	41.387	41.983	40.637	40.637	40.256
105	41.784	42.381	41.034	41.030	40.654
106	42.182	42.779	41.432	41.432	41.052
107	42.580	43.177	41.830	41.825	41.450
108	42.978	43.575	42.228	42.228	41.848
109	43.376	43.973	42.626	42.621	42.246
110	43.774	44.371	43.024	43.024	42.644
111	44.171	44.769	43.421	43.417	43.042
112	44.569	45.167	43.819	43.819	43.440
113	44.967	45.565	44.217	44.213	43.838
114	45.365	45.963	44.615	44.615	44.236
115	45.763	46.361	45.013	45.008	44.634
116	46.161	46.759	45.411	45.411	45.032
117	46.558	47.157	45.808	45.804	45.430
118	46.956	47.555	46.206	46.206	45.828
119	47.354	47.953	46.604	46.600	46.226
120	47.752	48.350	47.002	47.002	46.624

PD = p / sin(180°/N) · OD = European practice within the ISO 606 range · BD = PD − roller Ø · CD = BD (even N) or PD·cos(90°/N) − roller Ø (odd N).