Overview
The Martin 40BS11-5/8 is a bored-to-size roller chain sprocket engineered for industrial power transmission applications. Featuring 11 teeth and a 1/2-inch pitch, this unit is designed to interface with #40 roller chains in single-strand configurations. Shaft-ready design means the sprocket comes with a finished 5/8-inch bore, integrated keyway, and setscrews—ready for mounting directly to your drive shaft with minimal setup.
Key Features
- Bored-to-Size (Type BS): Pre-machined 5/8-inch finished bore eliminates setup delays; keyway centered on tooth line for precision alignment
- High-Carbon Steel Construction: Durable material with consistent finish, meeting ANSI B29.1 standards
- Precision-Machined: Concentric bore-to-pitch-line tolerances minimize run-out and extend chain life
- Setscrew Fastening: Two setscrews included; compatible with standard shaft keys for secure, field-adjustable mounting
- Single-Strand Design: Optimized for standard #40 single-pitch roller chain applications
Technical Specifications
- Chain Type / Pitch: #40 chain / 1/2-inch pitch
- Number of Teeth: 11
- Bore Diameter: 5/8-inch (finished, bored-to-size)
- Outside Diameter: 2.003 inches
- Hub Diameter: 1-3/8 inches
- Bore Length (through-bore): 7/8 inch
- Keyway: 3/16 x 3/32 inch; centered on tooth line
- Fastening: Two 1/4-20 x 1/4-inch setscrews
- Material: High-carbon steel
- Strands: 1 (single-strand)
- Surface: Finished (not hardened teeth)
Typical Applications
Martin 40BS11-5/8 sprockets are widely used in:
- Industrial conveyor systems and material handling equipment
- Machinery drives requiring compact, 11-tooth pinion designs
- Food processing, packaging, and light-duty manufacturing automation
- Power transmission where quick-change or adjustable mounting is required
- Equipment retrofits and replacements in standardized chain drive systems
Compatibility & Replacements
Compatible With
- #40 roller chain (ANSI standard 1/2-inch pitch)
- Standard steel shafts from 5/8-inch to approximately 3/4-inch with appropriate bushing (verify shaft diameter before ordering)
- Conveyor frames, motor mounts, and industrial gearbox assemblies equipped for #40 chain
- Systems using single-strand, single-pitch roller chain configurations
Replaces / Drop-In Replacement For
The Martin 40BS11-5/8 is a standard replacement for any worn or damaged #40 chain sprocket with 11 teeth and 5/8-inch bore. Verify bore diameter, tooth count, and chain pitch before ordering to ensure proper fit. Worn Martin 40BS11 sprockets in any bore size (1/2-inch, 5/8-inch, 3/4-inch, 7/8-inch) can be exchanged for this unit if your shaft diameter is 5/8-inch.
Works With
- ANSI #40 standard roller chains and drive trains
- Shaft-mounted applications using 1/4-20 setscrews and 3/16 x 3/32-inch keyways
- Industrial automation platforms and motion control systems with roller chain power transmission
- Equipment designed to ANSI B29.1 roller chain and sprocket standards
