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Pilot Bore Sprockets – 1/2” Pitch Roller Chain Sprockets

At Bolton Engineering Products Ltd, we stock a full range of pilot bore sprockets designed for reliable, efficient power transmission in machinery, conveyors, automation systems, and chain-driven equipment.

These plain bore sprockets (Type A) have an unprepared bore and require a keyway and set screw for installation, allowing them to be fully customized to fit any shaft size and meet your specific needs.

BEP Ltd have you covered – whether it be a light-duty sprocket or an item designed for continuous use, all our parts are made from high-strength materials and custom machined to tight tolerances at very competitive prices.

What Is a Pilot Bore Sprocket?

A pilot bore sprocket is a chain sprocket supplied with a basic, oversized bore, allowing engineers or machinists to finish-machine it to the exact shaft diameter or keyway required.

These sprockets are popular in:

  • Manufacturing & processing equipment
  • Agricultural and industrial machinery
  • Conveyors and material handling systems
  • Motorcycles, bicycles & chain-driven vehicles
  • General engineering and fabrication workshops

Their flexibility makes them a go-to choice for custom drive systems and OEM applications.

Technical Specifications

Specification

Details

Product Type

Pilot Bore / Plain Bore Sprocket

Chain Pitch

1/2” Pitch (BS Standard Roller Chain)

Tooth Count Options

8T to 50T+

Material

C45 Steel / Hardened Steel

Bore Type

Pilot Bore (Machinable to Required Shaft Size)

Mounting Style

Direct Shaft, Hub, or Bushing Mount

Tooth Profile

British Standard (BS / ISO Chain)

Applications

Industrial, Agricultural, Conveyor, Mechanical Drives

Finish

Untreated / Phosphate / Black Oxide (model dependent)

Key Features & Benefits

  • Customizable Bore: Machine the bore and keyway exactly as required.
  • Smooth Power Transfer: Precisely machined teeth ensure accurate chain engagement.
  • High-quality Steel made: Any types of metal work, 5” Heavy Duty.
  • Large Size Range: Will work small equipment all the way up to large industrial machinery.
  • Also compatible with BS standard: Suits all 1/2" pitch standard roller chains.
  • Bulk order discount: Great for OEMs, garages and maintenance facilities.

Why Choose Bolton Engineering Products Ltd?

As one of the UK’s trusted suppliers of pilot bore sprockets, BEP Ltd offers:

  • Large inventory of plain bore sprockets in multiple tooth counts
  • High-quality components sourced from reliable manufacturers
  • Competitive prices with trade & bulk discounts
  • Expert technical support for sizing and application queries
  • Fast UK dispatch with reliable shipping options

When you need precision, durability, and flexibility, BEP Ltd has the right pilot bore sprocket for your job.

FAQs

Q1: What is the difference between a pilot bore sprocket and a finished bore sprocket?

A pilot bore sprocket has an oversized bore that requires machining. A finished bore sprocket comes pre-machined to a specific shaft size.

Q2: Is a pilot bore the same as a plain bore?

Yes — plain bore sprockets and pilot bore sprockets describe the same unfinished, machinable bore design.

Q3: Can I machine the bore myself?

Yes. Many customers machine the bore, keyway, and grub-screw holes in-house. We can also advise on machining allowances.

Q4: Are these sprockets compatible with standard roller chains?

Absolutely. All our sprockets fit 1/2” pitch BS roller chains.

Roller Chain Pilot Bore Sprockets - 1/2"

Pilot Bore Sprockets – 1/2” Pitch Roller Chain Sprockets

At Bolton Engineering Products Ltd, we stock a full range of pilot bore sprockets designed for reliable, efficient power transmission in machinery, conveyors, automation systems, and chain-driven equipment.

These plain bore sprockets (Type A) have an unprepared bore and require a keyway and set screw for installation, allowing them to be fully customized to fit any shaft size and meet your specific needs.

BEP Ltd have you covered – whether it be a light-duty sprocket or an item designed for continuous use, all our parts are made from high-strength materials and custom machined to tight tolerances at very competitive prices.

What Is a Pilot Bore Sprocket?

A pilot bore sprocket is a chain sprocket supplied with a basic, oversized bore, allowing engineers or machinists to finish-machine it to the exact shaft diameter or keyway required.

These sprockets are popular in:

  • Manufacturing & processing equipment
  • Agricultural and industrial machinery
  • Conveyors and material handling systems
  • Motorcycles, bicycles & chain-driven vehicles
  • General engineering and fabrication workshops

Their flexibility makes them a go-to choice for custom drive systems and OEM applications.

Technical Specifications

Specification

Details

Product Type

Pilot Bore / Plain Bore Sprocket

Chain Pitch

1/2” Pitch (BS Standard Roller Chain)

Tooth Count Options

8T to 50T+

Material

C45 Steel / Hardened Steel

Bore Type

Pilot Bore (Machinable to Required Shaft Size)

Mounting Style

Direct Shaft, Hub, or Bushing Mount

Tooth Profile

British Standard (BS / ISO Chain)

Applications

Industrial, Agricultural, Conveyor, Mechanical Drives

Finish

Untreated / Phosphate / Black Oxide (model dependent)

Key Features & Benefits

  • Customizable Bore: Machine the bore and keyway exactly as required.
  • Smooth Power Transfer: Precisely machined teeth ensure accurate chain engagement.
  • High-quality Steel made: Any types of metal work, 5” Heavy Duty.
  • Large Size Range: Will work small equipment all the way up to large industrial machinery.
  • Also compatible with BS standard: Suits all 1/2" pitch standard roller chains.
  • Bulk order discount: Great for OEMs, garages and maintenance facilities.

Why Choose Bolton Engineering Products Ltd?

As one of the UK’s trusted suppliers of pilot bore sprockets, BEP Ltd offers:

  • Large inventory of plain bore sprockets in multiple tooth counts
  • High-quality components sourced from reliable manufacturers
  • Competitive prices with trade & bulk discounts
  • Expert technical support for sizing and application queries
  • Fast UK dispatch with reliable shipping options

When you need precision, durability, and flexibility, BEP Ltd has the right pilot bore sprocket for your job.

FAQs

Q1: What is the difference between a pilot bore sprocket and a finished bore sprocket?

A pilot bore sprocket has an oversized bore that requires machining. A finished bore sprocket comes pre-machined to a specific shaft size.

Q2: Is a pilot bore the same as a plain bore?

Yes — plain bore sprockets and pilot bore sprockets describe the same unfinished, machinable bore design.

Q3: Can I machine the bore myself?

Yes. Many customers machine the bore, keyway, and grub-screw holes in-house. We can also advise on machining allowances.

Q4: Are these sprockets compatible with standard roller chains?

Absolutely. All our sprockets fit 1/2” pitch BS roller chains.

4SR15 15mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 15 Tooth

£10.69 - £10.69
£10.69
£10.69 - £10.69
£10.69

Roller Chain Sprocket 08B 4SR15 15mm Bore Key & 2 Set Screws 1/2" Pitch 15 ToothChain Pitch:08B-1Number of Teeth:15Bore & Keyway(mm):15mmMf...

View full details
£10.69 - £10.69
£10.69
£10.69 - £10.69
£10.69

4SR14 25mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 14 Tooth

£10.38 - £10.38
£10.38
£10.38 - £10.38
£10.38

Roller Chain Sprocket 08B 4SR14 25mm Bore Key & 2 Set Screws 1/2" Pitch 14 ToothChain Pitch:08B-1Number of Teeth:14Bore & Keyway(mm):25mmMf...

View full details
£10.38 - £10.38
£10.38
£10.38 - £10.38
£10.38

4SR14 24mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 14 Tooth

£10.38 - £10.38
£10.38
£10.38 - £10.38
£10.38

Roller Chain Sprocket 08B 4SR14 24mm Bore Key & 2 Set Screws 1/2" Pitch 14 ToothChain Pitch:08B-1Number of Teeth:14Bore & Keyway(mm):24mmMf...

View full details
£10.38 - £10.38
£10.38
£10.38 - £10.38
£10.38

4SR14 22mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 14 Tooth

£10.38 - £10.38
£10.38
£10.38 - £10.38
£10.38

Roller Chain Sprocket 08B 4SR14 22mm Bore Key & 2 Set Screws 1/2" Pitch 14 ToothChain Pitch:08B-1Number of Teeth:14Bore & Keyway(mm):22mmMf...

View full details
£10.38 - £10.38
£10.38
£10.38 - £10.38
£10.38

4SR14 20mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 14 Tooth

£10.38 - £10.38
£10.38
£10.38 - £10.38
£10.38

Roller Chain Sprocket 08B 4SR14 20mm Bore Key & 2 Set Screws 1/2" Pitch 14 ToothChain Pitch:08B-1Number of Teeth:14Bore & Keyway(mm):20mmMf...

View full details
£10.38 - £10.38
£10.38
£10.38 - £10.38
£10.38

4SR14 19mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 14 Tooth

£10.38 - £10.38
£10.38
£10.38 - £10.38
£10.38

Roller Chain Sprocket 08B 4SR14 19mm Bore Key & 2 Set Screws 1/2" Pitch 14 ToothChain Pitch:08B-1Number of Teeth:14Bore & Keyway(mm):19mmMf...

View full details
£10.38 - £10.38
£10.38
£10.38 - £10.38
£10.38

4SR14 14mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 14 Tooth

£10.38 - £10.38
£10.38
£10.38 - £10.38
£10.38

Roller Chain Sprocket 08B 4SR14 14mm Bore Key & 2 Set Screws 1/2" Pitch 14 ToothChain Pitch:08B-1Number of Teeth:14Bore & Keyway(mm):14mmMf...

View full details
£10.38 - £10.38
£10.38
£10.38 - £10.38
£10.38

4SR13 24mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 13 Tooth

£9.93 - £9.93
£9.93
£9.93 - £9.93
£9.93

Roller Chain Sprocket 08B 4SR13 24mm Bore Key & 2 Set Screws 1/2" Pitch 13 ToothChain Pitch:08B-1Number of Teeth:13Bore & Keyway(mm):24mmMf...

View full details
£9.93 - £9.93
£9.93
£9.93 - £9.93
£9.93

4SR13 22mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 13 Tooth

£9.93 - £9.93
£9.93
£9.93 - £9.93
£9.93

Roller Chain Sprocket 08B 4SR13 22mm Bore Key & 2 Set Screws 1/2" Pitch 13 ToothChain Pitch:08B-1Number of Teeth:13Bore & Keyway(mm):22mmMf...

View full details
£9.93 - £9.93
£9.93
£9.93 - £9.93
£9.93

4SR13 20mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 13 Tooth

£9.93 - £9.93
£9.93
£9.93 - £9.93
£9.93

Roller Chain Sprocket 08B 4SR13 20mm Bore Key & 2 Set Screws 1/2" Pitch 13 ToothChain Pitch:08B-1Number of Teeth:13Bore & Keyway(mm):20mmMf...

View full details
£9.93 - £9.93
£9.93
£9.93 - £9.93
£9.93

4SR13 19mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 13 Tooth

£9.93 - £9.93
£9.93
£9.93 - £9.93
£9.93

Roller Chain Sprocket 08B 4SR13 19mm Bore Key & 2 Set Screws 1/2" Pitch 13 ToothChain Pitch:08B-1Number of Teeth:13Bore & Keyway(mm):19mmMf...

View full details
£9.93 - £9.93
£9.93
£9.93 - £9.93
£9.93

4SR13 18mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 13 Tooth

£9.93 - £9.93
£9.93
£9.93 - £9.93
£9.93

Roller Chain Sprocket 08B 4SR13 18mm Bore Key & 2 Set Screws 1/2" Pitch 13 ToothChain Pitch:08B-1Number of Teeth:13Bore & Keyway(mm):18mmMf...

View full details
£9.93 - £9.93
£9.93
£9.93 - £9.93
£9.93

4SR13 16mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 13 Tooth

£9.93 - £9.93
£9.93
£9.93 - £9.93
£9.93

Roller Chain Sprocket 08B 4SR13 16mm Bore Key & 2 Set Screws 1/2" Pitch 13 ToothChain Pitch:08B-1Number of Teeth:13Bore & Keyway(mm):16mmMf...

View full details
£9.93 - £9.93
£9.93
£9.93 - £9.93
£9.93

4SR13 15mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 13 Tooth

£9.93 - £9.93
£9.93
£9.93 - £9.93
£9.93

Roller Chain Sprocket 08B 4SR13 15mm Bore Key & 2 Set Screws 1/2" Pitch 13 ToothChain Pitch:08B-1Number of Teeth:13Bore & Keyway(mm):15mmMf...

View full details
£9.93 - £9.93
£9.93
£9.93 - £9.93
£9.93

4SR13 14mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 13 Tooth

£9.93 - £9.93
£9.93
£9.93 - £9.93
£9.93

Roller Chain Sprocket 08B 4SR13 14mm Bore Key & 2 Set Screws 1/2" Pitch 13 ToothChain Pitch:08B-1Number of Teeth:13Bore & Keyway(mm):14mmMf...

View full details
£9.93 - £9.93
£9.93
£9.93 - £9.93
£9.93

4SR13 12mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 13 Tooth

£9.93 - £9.93
£9.93
£9.93 - £9.93
£9.93

Roller Chain Sprocket 08B 4SR13 12mm Bore Key & 2 Set Screws 1/2" Pitch 13 ToothChain Pitch:08B-1Number of Teeth:13Bore & Keyway(mm):12mmMf...

View full details
£9.93 - £9.93
£9.93
£9.93 - £9.93
£9.93

4SR12 19mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 12 Tooth

£9.48 - £9.48
£9.48
£9.48 - £9.48
£9.48

Roller Chain Sprocket 08B 4SR12 19mm Bore Key & 2 Set Screws 1/2" Pitch 12 ToothChain Pitch:08B-1Number of Teeth:12Bore & Keyway(mm):19mmMf...

View full details
£9.48 - £9.48
£9.48
£9.48 - £9.48
£9.48

4SR12 16mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 12 Tooth

£9.48 - £9.48
£9.48
£9.48 - £9.48
£9.48

Roller Chain Sprocket 08B 4SR12 16mm Bore Key & 2 Set Screws 1/2" Pitch 12 ToothChain Pitch:08B-1Number of Teeth:12Bore & Keyway(mm):16mmMf...

View full details
£9.48 - £9.48
£9.48
£9.48 - £9.48
£9.48

4SR12 15mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 12 Tooth

£9.48 - £9.48
£9.48
£9.48 - £9.48
£9.48

Roller Chain Sprocket 08B 4SR12 15mm Bore Key & 2 Set Screws 1/2" Pitch 12 ToothChain Pitch:08B-1Number of Teeth:12Bore & Keyway(mm):15mmMf...

View full details
£9.48 - £9.48
£9.48
£9.48 - £9.48
£9.48

4SR12 14mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 12 Tooth

£9.48 - £9.48
£9.48
£9.48 - £9.48
£9.48

Roller Chain Sprocket 08B 4SR12 14mm Bore Key & 2 Set Screws 1/2" Pitch 12 ToothChain Pitch:08B-1Number of Teeth:12Bore & Keyway(mm):14mmMf...

View full details
£9.48 - £9.48
£9.48
£9.48 - £9.48
£9.48

4SR12 12mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 12 Tooth

£9.48 - £9.48
£9.48
£9.48 - £9.48
£9.48

Roller Chain Sprocket 08B 4SR12 12mm Bore Key & 2 Set Screws 1/2" Pitch 12 ToothChain Pitch:08B-1Number of Teeth:12Bore & Keyway(mm):12mmMf...

View full details
£9.48 - £9.48
£9.48
£9.48 - £9.48
£9.48

4SR11 19mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 11 Tooth

£10.14 - £10.14
£10.14
£10.14 - £10.14
£10.14

Roller Chain Sprocket 08B 4SR11 19mm Bore Key & 2 Set Screws 1/2" Pitch 11 ToothChain Pitch:08B-1Number of Teeth:11Bore & Keyway(mm):19mmMf...

View full details
£10.14 - £10.14
£10.14
£10.14 - £10.14
£10.14
ASA40-1-40--ANSI-Simplex-Roller-Chain-Sprocket-Pilot-Bore-#40-1/2"--40-Tooth

ASA40-1-40 - ANSI Simplex Roller Chain Sprocket Pilot Bore #40 1/2" - 40 Tooth

£0.00 - £0.00
£0.00
£0.00 - £0.00
£0.00

ASA40-1-40 - ANSI Simplex Roller Chain Sprocket Pilot Bore #40 1/2" - 40 Tooth

£0.00 - £0.00
£0.00
£0.00 - £0.00
£0.00
ASA40-1-38--ANSI-Simplex-Roller-Chain-Sprocket-Pilot-Bore-#40-1/2"--38-Tooth

ASA40-1-38 - ANSI Simplex Roller Chain Sprocket Pilot Bore #40 1/2" - 38 Tooth

£0.00 - £0.00
£0.00
£0.00 - £0.00
£0.00

ASA40-1-38 - ANSI Simplex Roller Chain Sprocket Pilot Bore #40 1/2" - 38 Tooth

£0.00 - £0.00
£0.00
£0.00 - £0.00
£0.00

Hi. Need any help?