Lugs with a ledge is a key visual feature of a new tyre from Alliance designed primarily for self-propelled sprayers, and lime, fertiliser and manure spreaders needing a combination of traction and high load-carrying capacity at modest inflation pressures.

These are currently catered for by the Agriflex+ 377, but the XT’s enhanced tread pattern is reckoned to offer better traction and roadability characteristics.

The Alliance Agriflex+ 377XT is a VF category tyre with a traction tread pattern that has been introduced in three sizes so far – VF 750/50 R26, VF 650/65 R38 and VF 620/70 R46.

See also: High-flexion tractor tyres; how they work and what they cost

Full specifications, including a load/speed index, have yet to be released other than for the 26in version, which has a load capacity of 6.7t at 3.2 bar for road travel from 40-65kph, 4.75t at 1.6 bar and 3t at just 0.8 bar.

Another three larger sizes are scheduled for release later this year – VF 1000/50 R25, VF 1050/50 R32 and VF 750/60 R46.

Lug design

A small tapered ledge projecting from part of the leading face of each lug comes from Alliance’s so-called “stratified layer” technology, whereby the lower half of the lug differs in shape from the upper half.

The bottom layer has a multi-angle profile so parts of it project beyond the single-angle upper half, effectively increasing the lug’s surface area while reinforcing the root of the lug.

Also claimed is a slower rate of wear than a conventionally-shaped lug once the upper layer has worn away, while maintaining the good road-going characteristics provided by a large lug-to-lug overlap that places a greater density of rubber around the centre of the tread pattern.

The “stratified layer” lug concept is also evident on Alliance’s otherwise conventional Agri Star II mainly 70- and 85-profile tractor tyres, but the Agriflex+ 377XT is its first appearance on a high-tech tyre.

As befits its heavy load-carrying role, the new tyre’s carcass is reinforced by a steel belt, while a tough compound protects against sharp stubble damage; the tyre is speed rated “D” for operation at up to 65kph.

Kirkby Tyres is Alliance’s UK distributor.