British Cycle Thread ( BSC )
British Cycle Thread Data(BSC) or (CEI) Cycle Engineers Institute
- This information is to be used for guide purposes only
- Some of these are out of use, but it's useful data - I always need it and can never find, hopefully you can too.......
| Diameter | Wire Gauge | TPI | Depth of Thread | Application | Drill Tap size | Clear Drill Size |
|---|---|---|---|---|---|---|
| 0.064 Inch | 16 SWG | 56 tpi | 0.095 inch | spokes | 56 | 51 |
| 0.072 Inch | 15 SWG | 56 tpi | 0.095 inch | spokes | 54 | 49 |
| 0.080 Inch | 14 SWG | 56 tpi | 0.095 inch | spokes | 1/16 inch | 46 |
| 0.092 Inch | 13 SWG | 56 tpi | 0.095 Inch | spokes | 48 | 3/32 |
| 0.104 Inch | 12 SWG | 56 tpi | 0.095 Inch | spokes | 44 | 36 |
| 1/8 Inch | 40 tpi | 0.0133 | free wheels | 38 | 30 | |
| 5/32 Inch(0.1563) | 32 tpi | 0.0166 Inch | small screw | 1/8 inch | 21 | |
| 3/16 ( 0.1875) | 32 tpi | 0.0166 Inch | chain adjust | 22 | 12 | |
| 1/4 Inch(0.25) | 26 tpi | 0.0205 Inch | crank cotter | 3 | 6.5mm | |
| 0.265 Inch | 26 tpi | 0.0205 Inch | crank cotter | 1 / 5.8mm | - | |
| 0.281 Inch | 26 tpi | 0.0205 Inch | general | D | L | |
| 5/16 Inch/0.3125 | 26tpi | 0.0205 Inch | general | J | O | |
| 9/16 Inch(0.5625) | 20tpi | 0.0266Inch | general | 13mm | 37/64 | |
| 5/8 Inch(0.625) | 26tpi | 0.0205 Inch | general | 15mm | 16mm | |
| 11/16 Inch(0.6875) | 26tpi | 0.205 Inch | general | 16.5mm | 45/64 | |
| 3/4 Inch(0.750) | 26tpi | 0.205 Inch | general | 18mm | 49/64 | |
| 7/8 Inch( 0.8750) | 24tpi | 0.225 Inch | Steer Column | 21.25mm | 57/64 | |
| 1 Inch | 24tpi | 0.0222 Inch | Steer Column | 15/16" | n/a | |
| 11/8 Inch | 26tpi | 0.205 | Steer Column | n/a | n/a | |