Ricoh Timing Pulley : T21

In motion control and automation, a pulley that slips or wears prematurely can bring your entire system to a halt. The Ricoh T21 Timing Pulley eliminates that risk with a precision-machined aluminum body and a trapezoidal T5 tooth profile that locks into compatible belts for reliable, backlash-free power transmission. With 21 teeth and a 5 mm bore, it is a drop-in replacement for many 3D printers, CNC machines, and light industrial drives, restoring smooth, repeatable motion without guesswork.

Who is it for

Engineers, technicians, and hobbyists who build or maintain motion systems—from desktop 3D printers and small CNC routers to packaging and automation equipment—will find this pulley essential. It suits anyone who needs a durable, dimensionally accurate timing pulley that resists wear and maintains belt alignment under continuous operation.

Main features

• 21-tooth T5 profile with 5 mm pitch for precise engagement with standard T5 belts.
• Double flanged design keeps the belt centered and prevents lateral drift, even at high speeds.
• Machined from aluminum alloy with a natural anodized finish for corrosion resistance and long service life.
• Plain bore with set screw holes allows secure mounting on a 5 mm shaft without keyways.
• Compact dimensions: 33.42 mm pitch diameter, 35 mm outside diameter, 7 mm face width, 10 mm overall length.
• Wide operating temperature range from -30°C to +100°C for demanding environments.

Specifications

• Pulley type: Timing pulley
• Profile: T-Profile (Trapezoidal), T5
• Number of teeth: 21
• Pitch: 5 mm
• Material: Aluminum alloy
• Bore diameter: 5 mm
• Bore type: Plain bore with set screw holes
• Flange type: Double flanged
• Compatible belt width: 6 mm
• Pitch diameter (PD): 33.42 mm
• Outside diameter (OD): approx. 35 mm
• Face width: 7 mm
• Hub diameter: 15 mm
• Overall length/height: 10 mm
• Finish: Natural anodized
• Operating temperature range: -30°C to +100°C
• Application: Motion control, automation, 3D printers, CNC machines

Tips

Before installation, verify that your belt matches the T5 profile and 6 mm width to ensure proper fit. Use a thread-locking compound on the set screws to prevent loosening from vibration. For best performance, align the pulley precisely with the mating pulley to minimize belt wear and noise.