Chain Dimensions (in millimeters)
The #35, #40, and BF05T are most common on large pocket bikes and choppers. The #25H is most common on scooters and the small 47cc pocket bike. Refer to the chart and image below to identify your chain.
| Chain Dimensions (in millimeters) |
| Chain No. |
Pitch |
Roller Diameter |
Width Between Inner Plates |
Pin Diameter |
Pin Length |
Inner Plate Depth |
Plate Thickness |
| |
P |
d1 max |
b1 min |
d2 max |
L max |
h2 max |
t/T max |
| #25 |
6.35 |
3.30 |
3.18 |
2.31 |
7.90 |
6.00 |
0.80 |
| #25H |
6.35 |
3.30 |
3.18 |
2.31 |
8.90 |
6.00 |
1.04 |
| BF05T |
8.00 |
4.71 |
4.61 |
3.05 |
11.48 |
7.60 |
1.3/1.04 |
| #35 |
9.53 |
5.08 |
4.77 |
3.58 |
12.40 |
9.00 |
1.30 |
| #40 |
12.70 |
7.95 |
7.85 |
3.96 |
16.60 |
12.00 |
1.50 |
| #081 |
12.70 |
7.75 |
3.30 |
3.66 |
11.20 |
9.91 |
0.90 |
| #219H |
7.774 |
4.59 |
5.00 |
3.01 |
11.90 |
7.40 |
1.2/1.04 |
| #270H |
8.50 |
5.00 |
4.75 |
3.28 |
13.15 |
8.45 |
1.8/1.4 |
| #415 |
12.70 |
7.77 |
4.76 |
3.60 |
11.00 |
9.70 |
1.00 |
| #415H |
12.70 |
7.77 |
4.76 |
3.96 |
13.10 |
12.00 |
1.50 |
| #420 |
12.70 |
7.77 |
6.25 |
3.96 |
14.70 |
12.00 |
1.50 |
| #428 |
12.70 |
8.51 |
7.75 |
4.45 |
16.70 |
11.80 |
1.60 |
| #428H |
12.70 |
8.51 |
7.85 |
4.45 |
18.80 |
11.80 |
2.03 |
| #520 |
15.875 |
10.16 |
6.25 |
5.08 |
17.50 |
15.09 |
2.03 |
| #525 |
15.875 |
10.16 |
7.95 |
5.08 |
19.30 |
15.09 |
2.03 |
| #530 |
15.875 |
10.16 |
9.40 |
5.08 |
20.70 |
15.09 |
2.03 |