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.
4SR20 35mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 20 Tooth
Original price
£14.55
-
Original price
£14.55
Original price
£14.55
£14.55
-
£14.55
Current price
£14.55
Roller Chain Sprocket 08B 4SR20 35mm Bore Key & 2 Set Screws 1/2" Pitch 20 ToothChain Pitch:08B-1Number of Teeth:20Bore & Keyway(mm):35mmMf...
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Original price
£14.55
-
Original price
£14.55
Original price
£14.55
£14.55
-
£14.55
Current price
£14.55
4SR20 32mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 20 Tooth
Original price
£14.55
-
Original price
£14.55
Original price
£14.55
£14.55
-
£14.55
Current price
£14.55
Roller Chain Sprocket 08B 4SR20 32mm Bore Key & 2 Set Screws 1/2" Pitch 20 ToothChain Pitch:08B-1Number of Teeth:20Bore & Keyway(mm):32mmMf...
View full details
Original price
£14.55
-
Original price
£14.55
Original price
£14.55
£14.55
-
£14.55
Current price
£14.55
4SR20 30mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 20 Tooth
Original price
£14.55
-
Original price
£14.55
Original price
£14.55
£14.55
-
£14.55
Current price
£14.55
Roller Chain Sprocket 08B 4SR20 30mm Bore Key & 2 Set Screws 1/2" Pitch 20 ToothChain Pitch:08B-1Number of Teeth:20Bore & Keyway(mm):30mmMf...
View full details
Original price
£14.55
-
Original price
£14.55
Original price
£14.55
£14.55
-
£14.55
Current price
£14.55
4SR20 24mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 20 Tooth
Original price
£14.55
-
Original price
£14.55
Original price
£14.55
£14.55
-
£14.55
Current price
£14.55
Roller Chain Sprocket 08B 4SR20 24mm Bore Key & 2 Set Screws 1/2" Pitch 20 ToothChain Pitch:08B-1Number of Teeth:20Bore & Keyway(mm):24mmMf...
View full details
Original price
£14.55
-
Original price
£14.55
Original price
£14.55
£14.55
-
£14.55
Current price
£14.55
4SR20 22mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 20 Tooth
Original price
£14.55
-
Original price
£14.55
Original price
£14.55
£14.55
-
£14.55
Current price
£14.55
Roller Chain Sprocket 08B 4SR20 22mm Bore Key & 2 Set Screws 1/2" Pitch 20 ToothChain Pitch:08B-1Number of Teeth:20Bore & Keyway(mm):22mmMf...
View full details
Original price
£14.55
-
Original price
£14.55
Original price
£14.55
£14.55
-
£14.55
Current price
£14.55
4SR20 20mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 20 Tooth
Original price
£14.55
-
Original price
£14.55
Original price
£14.55
£14.55
-
£14.55
Current price
£14.55
Roller Chain Sprocket 08B 4SR20 20mm Bore Key & 2 Set Screws 1/2" Pitch 20 ToothChain Pitch:08B-1Number of Teeth:20Bore & Keyway(mm):20mmMf...
View full details
Original price
£14.55
-
Original price
£14.55
Original price
£14.55
£14.55
-
£14.55
Current price
£14.55
4SR20 19mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 20 Tooth
Original price
£14.55
-
Original price
£14.55
Original price
£14.55
£14.55
-
£14.55
Current price
£14.55
Roller Chain Sprocket 08B 4SR20 19mm Bore Key & 2 Set Screws 1/2" Pitch 20 ToothChain Pitch:08B-1Number of Teeth:20Bore & Keyway(mm):19mmMf...
View full details
Original price
£14.55
-
Original price
£14.55
Original price
£14.55
£14.55
-
£14.55
Current price
£14.55
4SR19 35mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 19 Tooth
Original price
£13.79
-
Original price
£13.79
Original price
£13.79
£13.79
-
£13.79
Current price
£13.79
Roller Chain Sprocket 08B 4SR19 35mm Bore Key & 2 Set Screws 1/2" Pitch 19 ToothChain Pitch:08B-1Number of Teeth:19Bore & Keyway(mm):35mmMf...
View full details
Original price
£13.79
-
Original price
£13.79
Original price
£13.79
£13.79
-
£13.79
Current price
£13.79
4SR19 32mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 19 Tooth
Original price
£13.79
-
Original price
£13.79
Original price
£13.79
£13.79
-
£13.79
Current price
£13.79
Roller Chain Sprocket 08B 4SR19 32mm Bore Key & 2 Set Screws 1/2" Pitch 19 ToothChain Pitch:08B-1Number of Teeth:19Bore & Keyway(mm):32mmMf...
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Original price
£13.79
-
Original price
£13.79
Original price
£13.79
£13.79
-
£13.79
Current price
£13.79
4SR19 30mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 19 Tooth
Original price
£13.79
-
Original price
£13.79
Original price
£13.79
£13.79
-
£13.79
Current price
£13.79
Roller Chain Sprocket 08B 4SR19 30mm Bore Key & 2 Set Screws 1/2" Pitch 19 ToothChain Pitch:08B-1Number of Teeth:19Bore & Keyway(mm):30mmMf...
View full details
Original price
£13.79
-
Original price
£13.79
Original price
£13.79
£13.79
-
£13.79
Current price
£13.79
4SR19 28mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 19 Tooth
Original price
£13.79
-
Original price
£13.79
Original price
£13.79
£13.79
-
£13.79
Current price
£13.79
Roller Chain Sprocket 08B 4SR19 28mm Bore Key & 2 Set Screws 1/2" Pitch 19 ToothChain Pitch:08B-1Number of Teeth:19Bore & Keyway(mm):28mmMf...
View full details
Original price
£13.79
-
Original price
£13.79
Original price
£13.79
£13.79
-
£13.79
Current price
£13.79
4SR19 24mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 19 Tooth
Original price
£13.79
-
Original price
£13.79
Original price
£13.79
£13.79
-
£13.79
Current price
£13.79
Roller Chain Sprocket 08B 4SR19 24mm Bore Key & 2 Set Screws 1/2" Pitch 19 ToothChain Pitch:08B-1Number of Teeth:19Bore & Keyway(mm):24mmMf...
View full details
Original price
£13.79
-
Original price
£13.79
Original price
£13.79
£13.79
-
£13.79
Current price
£13.79
4SR19 20mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 19 Tooth
Original price
£13.79
-
Original price
£13.79
Original price
£13.79
£13.79
-
£13.79
Current price
£13.79
Roller Chain Sprocket 08B 4SR19 20mm Bore Key & 2 Set Screws 1/2" Pitch 19 ToothChain Pitch:08B-1Number of Teeth:19Bore & Keyway(mm):20mmMf...
View full details
Original price
£13.79
-
Original price
£13.79
Original price
£13.79
£13.79
-
£13.79
Current price
£13.79
4SR19 19mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 19 Tooth
Original price
£13.79
-
Original price
£13.79
Original price
£13.79
£13.79
-
£13.79
Current price
£13.79
Roller Chain Sprocket 08B 4SR19 19mm Bore Key & 2 Set Screws 1/2" Pitch 19 ToothChain Pitch:08B-1Number of Teeth:19Bore & Keyway(mm):19mmMf...
View full details
Original price
£13.79
-
Original price
£13.79
Original price
£13.79
£13.79
-
£13.79
Current price
£13.79
4SR18 35mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 18 Tooth
Original price
£12.73
-
Original price
£12.73
Original price
£12.73
£12.73
-
£12.73
Current price
£12.73
Roller Chain Sprocket 08B 4SR18 35mm Bore Key & 2 Set Screws 1/2" Pitch 18 ToothChain Pitch:08B-1Number of Teeth:18Bore & Keyway(mm):35mmMf...
View full details
Original price
£12.73
-
Original price
£12.73
Original price
£12.73
£12.73
-
£12.73
Current price
£12.73
4SR18 32mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 18 Tooth
Original price
£12.73
-
Original price
£12.73
Original price
£12.73
£12.73
-
£12.73
Current price
£12.73
Roller Chain Sprocket 08B 4SR18 32mm Bore Key & 2 Set Screws 1/2" Pitch 18 ToothChain Pitch:08B-1Number of Teeth:18Bore & Keyway(mm):32mmMf...
View full details
Original price
£12.73
-
Original price
£12.73
Original price
£12.73
£12.73
-
£12.73
Current price
£12.73
4SR18 30mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 18 Tooth
Original price
£12.73
-
Original price
£12.73
Original price
£12.73
£12.73
-
£12.73
Current price
£12.73
Roller Chain Sprocket 08B 4SR18 30mm Bore Key & 2 Set Screws 1/2" Pitch 18 ToothChain Pitch:08B-1Number of Teeth:18Bore & Keyway(mm):30mmMf...
View full details
Original price
£12.73
-
Original price
£12.73
Original price
£12.73
£12.73
-
£12.73
Current price
£12.73
4SR18 28mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 18 Tooth
Original price
£12.73
-
Original price
£12.73
Original price
£12.73
£12.73
-
£12.73
Current price
£12.73
Roller Chain Sprocket 08B 4SR18 28mm Bore Key & 2 Set Screws 1/2" Pitch 18 ToothChain Pitch:08B-1Number of Teeth:18Bore & Keyway(mm):28mmMf...
View full details
Original price
£12.73
-
Original price
£12.73
Original price
£12.73
£12.73
-
£12.73
Current price
£12.73
4SR18 24mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 18 Tooth
Original price
£12.73
-
Original price
£12.73
Original price
£12.73
£12.73
-
£12.73
Current price
£12.73
Roller Chain Sprocket 08B 4SR18 24mm Bore Key & 2 Set Screws 1/2" Pitch 18 ToothChain Pitch:08B-1Number of Teeth:18Bore & Keyway(mm):24mmMf...
View full details
Original price
£12.73
-
Original price
£12.73
Original price
£12.73
£12.73
-
£12.73
Current price
£12.73
4SR18 22mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 18 Tooth
Original price
£12.73
-
Original price
£12.73
Original price
£12.73
£12.73
-
£12.73
Current price
£12.73
Roller Chain Sprocket 08B 4SR18 22mm Bore Key & 2 Set Screws 1/2" Pitch 18 ToothChain Pitch:08B-1Number of Teeth:18Bore & Keyway(mm):22mmMf...
View full details
Original price
£12.73
-
Original price
£12.73
Original price
£12.73
£12.73
-
£12.73
Current price
£12.73
4SR18 20mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 18 Tooth
Original price
£12.73
-
Original price
£12.73
Original price
£12.73
£12.73
-
£12.73
Current price
£12.73
Roller Chain Sprocket 08B 4SR18 20mm Bore Key & 2 Set Screws 1/2" Pitch 18 ToothChain Pitch:08B-1Number of Teeth:18Bore & Keyway(mm):20mmMf...
View full details
Original price
£12.73
-
Original price
£12.73
Original price
£12.73
£12.73
-
£12.73
Current price
£12.73
4SR18 18mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 18 Tooth
Original price
£12.73
-
Original price
£12.73
Original price
£12.73
£12.73
-
£12.73
Current price
£12.73
Roller Chain Sprocket 08B 4SR18 18mm Bore Key & 2 Set Screws 1/2" Pitch 18 ToothChain Pitch:08B-1Number of Teeth:18Bore & Keyway(mm):18mmMf...
View full details
Original price
£12.73
-
Original price
£12.73
Original price
£12.73
£12.73
-
£12.73
Current price
£12.73
4SR18 16mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 18 Tooth
Original price
£12.73
-
Original price
£12.73
Original price
£12.73
£12.73
-
£12.73
Current price
£12.73
Roller Chain Sprocket 08B 4SR18 16mm Bore Key & 2 Set Screws 1/2" Pitch 18 ToothChain Pitch:08B-1Number of Teeth:18Bore & Keyway(mm):16mmMf...
View full details
Original price
£12.73
-
Original price
£12.73
Original price
£12.73
£12.73
-
£12.73
Current price
£12.73
4SR17 30mm Bore, Keyway & Grub Screws Roller Chain Sprocket 1/2" Pitch 17 Tooth
Original price
£12.06
-
Original price
£12.06
Original price
£12.06
£12.06
-
£12.06
Current price
£12.06
Roller Chain Sprocket 08B 4SR17 30mm Bore Key & 2 Set Screws 1/2" Pitch 17 ToothChain Pitch:08B-1Number of Teeth:17Bore & Keyway(mm):30mmMf...
View full details
Original price
£12.06
-
Original price
£12.06
Original price
£12.06
£12.06
-
£12.06
Current price
£12.06