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

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.

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4TR38C (08B-3-38) - BS Triplex Roller Chain Sprocket Pilot Bore 08B 1/2" - 38 Tooth

£50.08 - £50.08

£50.08

£50.08 - £50.08

£50.08

4TR38C (08B-3-38) - BS Triplex Roller Chain Sprocket Pilot Bore 08B 1/2" - 38 Tooth

£50.08 - £50.08

£50.08

£50.08 - £50.08

£50.08

4TR45C (08B-3-45) - BS Triplex Roller Chain Sprocket Pilot Bore 08B 1/2" - 45 Tooth

£51.99 - £51.99

£51.99

£51.99 - £51.99

£51.99

4TR45C (08B-3-45) - BS Triplex Roller Chain Sprocket Pilot Bore 08B 1/2" - 45 Tooth

£51.99 - £51.99

£51.99

£51.99 - £51.99

£51.99

4TR57C (08B-3-57) - BS Triplex Roller Chain Sprocket Pilot Bore 08B 1/2" - 57 Tooth

£78.64 - £78.64

£78.64

£78.64 - £78.64

£78.64

4TR57C (08B-3-57) - BS Triplex Roller Chain Sprocket Pilot Bore 08B 1/2" - 57 Tooth

£78.64 - £78.64

£78.64

£78.64 - £78.64

£78.64

4TR76C (08B-3-76) - BS Triplex Roller Chain Sprocket Pilot Bore 08B 1/2" - 76 Tooth

£118.46 - £118.46

£118.46

£118.46 - £118.46

£118.46

4TR76C (08B-3-76) - BS Triplex Roller Chain Sprocket Pilot Bore 08B 1/2" - 76 Tooth

£118.46 - £118.46

£118.46

£118.46 - £118.46

£118.46

4TR95C (08B-3-95) - BS Triplex Roller Chain Sprocket Pilot Bore 08B 1/2" - 95 Tooth

£162.27 - £162.27

£162.27

£162.27 - £162.27

£162.27

4TR95C (08B-3-95) - BS Triplex Roller Chain Sprocket Pilot Bore 08B 1/2" - 95 Tooth

£162.27 - £162.27

£162.27

£162.27 - £162.27

£162.27

4SR30 38mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 30 Tooth

£22.13 - £22.13

£22.13

£22.13 - £22.13

£22.13

Roller Chain Sprocket 08B 4SR30 38mm Bore Key & 2 Set Screws 1/2" Pitch 30 ToothChain Pitch:08B-1Number of Teeth:30Bore & Keyway(mm):38mmMf...

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£22.13 - £22.13

£22.13

£22.13 - £22.13

£22.13

4SR30 28mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 30 Tooth

£22.13 - £22.13

£22.13

£22.13 - £22.13

£22.13

Roller Chain Sprocket 08B 4SR30 28mm Bore Key & 2 Set Screws 1/2" Pitch 30 ToothChain Pitch:08B-1Number of Teeth:30Bore & Keyway(mm):28mmMf...

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£22.13 - £22.13

£22.13

£22.13 - £22.13

£22.13

4SR25 38mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 25 Tooth

£17.06 - £17.06

£17.06

£17.06 - £17.06

£17.06

Roller Chain Sprocket 08B 4SR25 38mm Bore Key & 2 Set Screws 1/2" Pitch 25 ToothChain Pitch:08B-1Number of Teeth:25Bore & Keyway(mm):38mmMf...

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£17.06 - £17.06

£17.06

£17.06 - £17.06

£17.06

4SR25 35mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 25 Tooth

£17.06 - £17.06

£17.06

£17.06 - £17.06

£17.06

Roller Chain Sprocket 08B 4SR25 35mm Bore Key & 2 Set Screws 1/2" Pitch 25 ToothChain Pitch:08B-1Number of Teeth:25Bore & Keyway(mm):35mmMf...

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£17.06 - £17.06

£17.06

£17.06 - £17.06

£17.06

4SR25 30mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 25 Tooth

£17.06 - £17.06

£17.06

£17.06 - £17.06

£17.06

Roller Chain Sprocket 08B 4SR25 30mm Bore Key & 2 Set Screws 1/2" Pitch 25 ToothChain Pitch:08B-1Number of Teeth:25Bore & Keyway(mm):30mmMf...

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£17.06 - £17.06

£17.06

£17.06 - £17.06

£17.06

4SR25 28mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 25 Tooth

£17.06 - £17.06

£17.06

£17.06 - £17.06

£17.06

Roller Chain Sprocket 08B 4SR25 28mm Bore Key & 2 Set Screws 1/2" Pitch 25 ToothChain Pitch:08B-1Number of Teeth:25Bore & Keyway(mm):28mmMf...

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£17.06 - £17.06

£17.06

£17.06 - £17.06

£17.06

4SR25 24mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 25 Tooth

£17.06 - £17.06

£17.06

£17.06 - £17.06

£17.06

Roller Chain Sprocket 08B 4SR25 24mm Bore Key & 2 Set Screws 1/2" Pitch 25 ToothChain Pitch:08B-1Number of Teeth:25Bore & Keyway(mm):24mmMf...

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£17.06 - £17.06

£17.06

£17.06 - £17.06

£17.06

4SR25 22mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 25 Tooth

£17.06 - £17.06

£17.06

£17.06 - £17.06

£17.06

Roller Chain Sprocket 08B 4SR25 22mm Bore Key & 2 Set Screws 1/2" Pitch 25 ToothChain Pitch:08B-1Number of Teeth:25Bore & Keyway(mm):22mmMf...

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£17.06 - £17.06

£17.06

£17.06 - £17.06

£17.06

4SR24 38mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 24 Tooth

£16.04 - £16.04

£16.04

£16.04 - £16.04

£16.04

Roller Chain Sprocket 08B 4SR24 38mm Bore Key & 2 Set Screws 1/2" Pitch 24 ToothChain Pitch:08B-1Number of Teeth:24Bore & Keyway(mm):38mmMf...

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£16.04 - £16.04

£16.04

£16.04 - £16.04

£16.04

4SR24 35mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 24 Tooth

£16.04 - £16.04

£16.04

£16.04 - £16.04

£16.04

Roller Chain Sprocket 08B 4SR24 35mm Bore Key & 2 Set Screws 1/2" Pitch 24 ToothChain Pitch:08B-1Number of Teeth:24Bore & Keyway(mm):35mmMf...

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£16.04 - £16.04

£16.04

£16.04 - £16.04

£16.04

4SR24 32mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 24 Tooth

£16.04 - £16.04

£16.04

£16.04 - £16.04

£16.04

Roller Chain Sprocket 08B 4SR24 32mm Bore Key & 2 Set Screws 1/2" Pitch 24 ToothChain Pitch:08B-1Number of Teeth:24Bore & Keyway(mm):32mmMf...

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£16.04 - £16.04

£16.04

£16.04 - £16.04

£16.04

4SR24 30mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 24 Tooth

£16.04 - £16.04

£16.04

£16.04 - £16.04

£16.04

Roller Chain Sprocket 08B 4SR24 30mm Bore Key & 2 Set Screws 1/2" Pitch 24 ToothChain Pitch:08B-1Number of Teeth:24Bore & Keyway(mm):30mmMf...

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£16.04 - £16.04

£16.04

£16.04 - £16.04

£16.04

4SR24 25mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 24 Tooth

£16.04 - £16.04

£16.04

£16.04 - £16.04

£16.04

Roller Chain Sprocket 08B 4SR24 25mm Bore Key & 2 Set Screws 1/2" Pitch 24 ToothChain Pitch:08B-1Number of Teeth:24Bore & Keyway(mm):25mmMf...

View full details

£16.04 - £16.04

£16.04

£16.04 - £16.04

£16.04

4SR24 22mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 24 Tooth

£16.04 - £16.04

£16.04

£16.04 - £16.04

£16.04

Roller Chain Sprocket 08B 4SR24 22mm Bore Key & 2 Set Screws 1/2" Pitch 24 ToothChain Pitch:08B-1Number of Teeth:24Bore & Keyway(mm):22mmMf...

View full details

£16.04 - £16.04

£16.04

£16.04 - £16.04

£16.04

4SR24 20mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 24 Tooth

£16.04 - £16.04

£16.04

£16.04 - £16.04

£16.04

Roller Chain Sprocket 08B 4SR24 20mm Bore Key & 2 Set Screws 1/2" Pitch 24 ToothChain Pitch:08B-1Number of Teeth:24Bore & Keyway(mm):20mmMf...

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£16.04 - £16.04

£16.04

£16.04 - £16.04

£16.04

4SR23 38mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 23 Tooth

£15.31 - £15.31

£15.31

£15.31 - £15.31

£15.31

Roller Chain Sprocket 08B 4SR23 38mm Bore Key & 2 Set Screws 1/2" Pitch 23 ToothChain Pitch:08B-1Number of Teeth:23Bore & Keyway(mm):38mmMf...

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£15.31 - £15.31

£15.31

£15.31 - £15.31

£15.31

4SR23 35mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 23 Tooth

£15.31 - £15.31

£15.31

£15.31 - £15.31

£15.31

Roller Chain Sprocket 08B 4SR23 35mm Bore Key & 2 Set Screws 1/2" Pitch 23 ToothChain Pitch:08B-1Number of Teeth:23Bore & Keyway(mm):35mmMf...

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£15.31 - £15.31

£15.31

£15.31 - £15.31

£15.31

4SR23 32mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 23 Tooth

£15.31 - £15.31

£15.31

£15.31 - £15.31

£15.31

Roller Chain Sprocket 08B 4SR23 32mm Bore Key & 2 Set Screws 1/2" Pitch 23 ToothChain Pitch:08B-1Number of Teeth:23Bore & Keyway(mm):32mmMf...

View full details

£15.31 - £15.31

£15.31

£15.31 - £15.31

£15.31

4SR23 28mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 23 Tooth

£15.31 - £15.31

£15.31

£15.31 - £15.31

£15.31

Roller Chain Sprocket 08B 4SR23 28mm Bore Key & 2 Set Screws 1/2" Pitch 23 ToothChain Pitch:08B-1Number of Teeth:23Bore & Keyway(mm):28mmMf...

View full details

£15.31 - £15.31

£15.31

£15.31 - £15.31

£15.31

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

What Is a Pilot Bore Sprocket?

Technical Specifications

Key Features & Benefits

Why Choose Bolton Engineering Products Ltd?

FAQs

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

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

Q3: Can I machine the bore myself?

Q4: Are these sprockets compatible with standard roller chains?

Roller Chain Pilot Bore Sprockets - 1/2"

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

What Is a Pilot Bore Sprocket?

Technical Specifications

Key Features & Benefits

Why Choose Bolton Engineering Products Ltd?

FAQs

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

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

Q3: Can I machine the bore myself?

Q4: Are these sprockets compatible with standard roller chains?