Description
Plain Bore Yoke — H-Pin Hole & Threaded Hole
Designed for demanding agricultural and industrial power transmission applications across the United Kingdom, the Plain Bore Yoke with H-Pin Hole and Threaded Hole delivers the reliable connection between PTO drive shafts and implement input flanges that British farmers and machinery operators have trusted for decades.
Why Choose Our Plain Bore Yoke H-Pin & Threaded Hole?
British agricultural and industrial operations place extreme demands on every component in a PTO drive shaft assembly. Soil conditions, seasonal load spikes, and the mix of legacy and modern implements mean that a standard yoke simply is not enough. Our Plain Bore Yoke with H-Pin Hole and Threaded Hole addresses this reality with a design refined over many production cycles and validated in real field conditions. The through-pin hole running perpendicular to the shaft bore provides a positive mechanical lock, while the threaded hole accepts a grub screw or set bolt for secondary retention — preventing the yoke from loosening due to vibration or torque reversal. This dual-fastening approach is especially valued on reversible implements such as rotary cultivators and power harrows, where abrupt direction changes would otherwise migrate a single-retention yoke along the shaft spline.
Dual-Retention Security
H-pin hole plus threaded grub-screw seat prevents axial migration on high-vibration implements and reversible drives.
High-Grade Steel Construction
Forged and machined from carbon steel with surface hardening options; optimised for torque density without adding unnecessary weight.
Wide Size Range
Available in multiple bore diameters and shaft series, covering common UK tractor PTO outputs from compact utility tractors to high-horsepower field machines.
Interchangeable & Standardised
Dimensionally compatible with major European and ISO PTO shaft standards, enabling straightforward replacement and cross-series fitment on established UK fleets.
Custom Bore & Finish Options
Non-standard bore diameters, keyway combinations, and phosphate or zinc-plated surface treatments available on request for OEM and fleet rebuild programmes.
Technical Specification
The Plain Bore Yoke H-Pin Hole & Threaded Hole is engineered to precise dimensional standards, ensuring consistent fit across all major PTO drive shaft series. Below are the full technical parameters. The engineering drawing provides reference dimensions for bore, pin-hole, and threaded-hole positions — critical data for our UK dealer and OEM customers when specifying replacement or custom assemblies.

Engineering drawing — Plain Bore Yoke H-Pin Hole & Threaded Hole
* Custom bore sizes, keyway options, and surface treatments available on request. All dimensions ±0.05 mm tolerance unless otherwise specified. Contact our technical team for non-standard configurations.
Material, Working Principle & Application Scenarios
🪓 Material
The yoke body is forged from medium-carbon steel (typical grade: C45 / EN8) or alloy steel (42CrMo4 / EN19) depending on the torque series. After rough machining, the bore and yoke ears undergo normalising heat treatment to refine grain structure and eliminate internal stress. Critical surfaces — the bore inner diameter, pin-hole, and ear faces — are finish-ground to tight tolerances. A phosphate conversion coating is applied as standard, giving a uniform grey surface that promotes lubricant retention and provides moderate corrosion protection suitable for outdoor UK agricultural use. Zinc-electroplate and hot-dip galvanising options are available where longer-term corrosion resistance is required, for instance on coastal farms in Devon, Cornwall, or the Scottish islands.
⚙ Working Principle
The plain bore accepts the stub end of a PTO drive shaft tube or implement input stub with a close-clearance sliding fit. Rotary torque is transmitted through friction clamping and the cross-pin, which passes through the H-pin hole drilled perpendicular to the shaft axis. The threaded hole, positioned 90° to the pin hole or offset along the hub length depending on the variant, takes an M8–M14 set bolt that bears onto a flat ground on the shaft stub — providing the secondary retention that prevents rotation of the yoke relative to the shaft under shock-reversal conditions. This combination is fully compliant with ISO 8210 requirements for PTO stub shaft connections and mirrors the design philosophy used by leading UK tractor manufacturers including John Deere, New Holland, and AGCO brands for their European-spec machines.
🌿 Application Scenarios
Plain Bore Yokes with H-Pin and Threaded Hole are found throughout UK agriculture and light industrial sectors. On arable farms in Lincolnshire and East Anglia, they connect PTO drive shafts to rotary cultivators, power harrows, and fertiliser spreaders. Livestock farms in Wales and Cumbria rely on them for slurry stirrers and muck spreaders. In horticulture, the compact G Series variant is popular for ride-on flail mowers and rotary cutters on market garden holdings. Beyond agriculture, the same yoke designs appear in industrial settings: driving water pumps on construction sites, operating hydraulic log splitters, and connecting PTO-driven generators at rural events and remote UK facilities where grid power is unavailable.

Complete PTO Drive Shaft Series
The Plain Bore Yoke H-Pin & Threaded Hole is a core component across our full range of PTO drive shaft series. Each series is engineered to a specific torque class and application profile, giving UK distributors and OEM customers a coherent product ladder from compact utility machines right through to high-power arable tractors. Click any series below for full product details and configuration options.
PTO Drive Shaft G Series
Light to medium duty. Ideal for compact tractors, ride-on mowers, and horticultural equipment up to ~30 hp PTO output.
PTO Drive Shaft S Series
Standard agricultural duty. Covers the majority of UK farm implement connections from 30–80 hp tractor PTO outputs.
PTO Drive Shaft L Series
Heavy-duty long-reach shafts for large-scale arable and contractor use. Suited to 80–150 hp machines and demanding field conditions.
PTO Drive Shaft T Series
Torque-class heavy industrial and specialist applications, including high-horsepower tillage equipment and PTO-driven industrial machinery.
Customer Success: Midlands Agricultural Contractor
Warwickshire Arable Contracting Business — PTO Shaft Fleet Rebuild
🏭 Agricultural Contracting · Warwickshire, UK · Fleet of 14 tractors
A well-established agricultural contractor running fourteen tractors across Warwickshire and the surrounding counties came to us after experiencing repeated PTO shaft failures during the autumn cultivations campaign. Their existing yokes — sourced from a local factor as generic replacements — were slipping on the stub shaft under the shock loads generated by a high-output power harrow. Three yoke failures in a single week caused costly downtime during the narrow drilling window after sugar beet harvest.
We supplied a batch of 28 Plain Bore Yoke H-Pin & Threaded Hole units in L Series specification, replacing all power harrow input and tractor output yokes across the fleet. The contractor’s workshop fitted them over a single weekend using our supplied dimensional drawings and torque guidance. The following eight weeks of heavy cultivating — including a particularly wet October that pushed hourly loads well above design average — passed without a single PTO-related stoppage.
“We’ve tried three different suppliers over the years. These are the first yokes that have actually stayed put under the power harrow. The dual-pin-and-bolt setup makes all the difference — nothing moves, not even in the wet.”
— Workshop Manager, Warwickshire Arable Contracting Ltd
What UK Customers Say
“Ordered twelve L-Series yokes for our slurry equipment. Quality is noticeably better than what we had before — the machining on the bore is clean and the pin holes line up perfectly. Delivery to Yorkshire was faster than expected.”
David H.
Dairy Farm, North Yorkshire
“We needed a non-standard bore size for a bespoke PTO pump installation on a water treatment site in Essex. The technical team sorted it quickly, provided drawings for approval, and the parts arrived within the quoted lead time. Will use again.”
Mark T.
Industrial Equipment Installer, Essex
“As a spare parts distributor covering the Scottish Borders, I need reliable stock that fits first time. These plain bore yokes have been consistent across three separate orders now — dimensions are spot on and the finish is solid. Competitive price for the quality.”
Fiona M.
Agricultural Parts Distributor, Scottish Borders
Manufacturing Facility & Custom Engineering Capability
Our production facility operates a vertically integrated process for PTO drive shaft yokes and components. From billet steel forging through to finish machining, heat treatment, surface coating, and dimensional inspection, every Plain Bore Yoke H-Pin & Threaded Hole unit is manufactured under one roof. CNC turning centres with live tooling handle the bore, pin hole, and threaded hole operations in a single setup, removing the cumulative tolerancing error that multi-machine processes introduce. A CMM (coordinate measuring machine) inspection cell samples each production batch to ISO inspection standards, with full dimensional reports available to UK OEM customers on request.
Custom engineering is a genuine strength of our operation, not a marketing phrase. UK machinery manufacturers, rebuilders, and specialist contractors regularly approach us with non-standard requirements: alternative bore diameters in 0.5 mm increments, metric and imperial keyway combinations, combined pin-hole and splined bore configurations, or one-piece forged yoke-shaft sub-assemblies for high-volume OEM programmes. Our engineering team can work from customer drawings, sample parts, or a dimensional brief and will return a quotation with a DXF drawing for approval. Minimum order quantities for custom parts are flexible, making us equally accessible to small rebuilders and large OEM customers across England, Scotland, Wales, and Northern Ireland.

CNC machining centre — bore & pin hole operations
Custom PTO Components for UK OEM & Rebuild
Non-standard bores, keyways, coatings, and shaft series available. Technical drawings supplied. Flexible MOQ.
Frequently Asked Questions
Ready to Order or Need Technical Advice?
Our team is ready to support UK B2B customers with product selection, custom specifications, and volume pricing. Reach us directly by email for the fastest response.


