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- 28B-1 Chain Number
- 1 Strand
- 21 Teeth
- Without Hardened Teeth
- B Sprocket Style
description
- Maximum bores shown will accommodate standard keyseat and setscrew over keyseat. Slightly larger bores are possible with no keyseat, shallow keyseat, or setscrew at an angle to keyseat.
features
- Precise machining and processes ensure consistent finish and high quality
- Manufactured of high carbon steel
- Bores are concentric to pitch line, minimizing run out
- Chain rows are parallel and precisely spaced to increase longevity of sprocket and chain
| Length Through Bore | 64.01 mm |
| Hardened Teeth | Without Hardened Teeth |
| Pitch Diameter [Min] | 298.2 mm |
| Bore Range [Min] | 40.11 mm |
| Pitch Diameter | 298.2 mm |
| Bore Range [Max] | 108 mm |
| Pitch Root Diameter | 270.3 mm |
| Chain Pitch | 44.45 mm |
| Hub Length Thru | 64 mm |
| No. of Strands Across | 1 |
| Bore Type | Reborable |
| Width Across Teeth | 29.44 mm |
| Single Strand Tooth Thickness | 29.44 mm |
| Material | Steel |
| Caliper Diameter | 269.46 mm |
| Series | B |
| Outside Dia. | 325.86 mm |
| Outside Dia. [Min] | 325.86 mm |
| Pin Diameter | 27.94 mm |
| Inch/Metric | Metric |
| Martin No. | 28B21 |
| Sprocket Style | B |
| Hub Dia. | 159.99 mm |
| No. of Teeth | 21 |
| Chain No. | 28B, 28B-1 |
| Root Diameter | 270.3 mm |
| Bore Style | Minimum Bore |
| Family Name | No. 28 - 44.450 mm Pitch - Single - Type B & C |
| Weight | 42.89 LB |
| EAN or UPC | 697950406725 |
