Chain Chart
Use the image below to guide you in measuring your chain.
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. | Part 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 | 115-5 | 6.35 | 3.3 | 3.18 | 2.31 | 7.9 | 6 | 0.8 |
| #25H | 115-84 | 6.35 | 3.3 | 3.18 | 2.31 | 8.9 | 6 | 1.04 |
| BF05T | 115-10 | 8 | 4.71 | 4.61 | 3.05 | 11.48 | 7.6 | 1.3/1.04 |
| T8F | 115-92 | 8 | 4.77 | 4.72 | 3.28 | 11.7 | 7.6 | 0.8 |
| #35 | 115-83 | 9.53 | 5.08 | 4.77 | 3.58 | 12.4 | 9 | 1.3 |
| #40 | 115-87 | 12.7 | 7.95 | 7.85 | 3.96 | 16.6 | 12 | 1.5 |
| #081 | 115-19 | 12.7 | 7.75 | 3.3 | 3.66 | 11.2 | 9.91 | 0.9 |
| #219H | 115-4 | 7.774 | 4.59 | 5 | 3.01 | 11.9 | 7.4 | 1.2/1.04 |
| #270H | 115-81 | 8.5 | 5 | 4.75 | 3.28 | 13.15 | 8.45 | 1.8/1.4 |
| #415 | 115-86 | 12.7 | 7.77 | 4.76 | 3.6 | 11 | 9.7 | 1 |
| #415H | 115-78 | 12.7 | 7.77 | 4.76 | 3.96 | 13.1 | 12 | 1.5 |
| #420 | 115-85 | 12.7 | 7.77 | 6.25 | 3.96 | 14.7 | 12 | 1.5 |
| #428 | 115-88 | 12.7 | 8.51 | 7.75 | 4.45 | 16.7 | 11.8 | 1.6 |
| #428H | 115-89 | 12.7 | 8.51 | 7.85 | 4.45 | 18.8 | 11.8 | 2.03 |
| #520 | 115-66 | 15.875 | 10.16 | 6.25 | 5.08 | 17.5 | 15.09 | 2.03 |
| #525 | 115-91 | 15.875 | 10.16 | 7.95 | 5.08 | 19.3 | 15.09 | 2.03 |
| #530 | 115-90 | 15.875 | 10.16 | 9.4 | 5.08 | 20.7 | 15.09 | 2.03 |