Gum Sole Care Guide

A gum sole is natural rubber left close to its raw colour. It grips better than most synthetic compounds, it wears slowly, and it changes as you use it. Here is how to look after it — and what is worth accepting rather than fighting.

What gum actually is

Gum rubber is tapped from the rubber tree and processed with minimal pigment, which is why it comes out that warm translucent amber. Synthetic outsoles are coloured to spec and stay that colour. Gum does not.

The trade-off is deliberate: gum has a higher coefficient of friction than most moulded rubber, which is exactly why it became standard on court and skate silhouettes decades ago. You get grip and slow wear, and in exchange the sole ages visibly.

Why gum darkens — and what you can do

Gum oxidises. Exposure to oxygen and ultraviolet light gradually deepens the amber toward a brown-caramel. It is a chemical process in the rubber itself, not dirt sitting on the surface, and it cannot be reversed.

What speeds it up:

Direct sunlight, including through a window
Heat — radiators, car boots in summer, drying near a heater
Long storage in a clear plastic box on a bright shelf

What slows it down:

Store the pair in its box, or in a dark cupboard
Keep them away from radiators and out of direct sun
Clean the sole regularly so ground-in dirt does not compound the colour shift

Some darkening is unavoidable, and most people come to prefer it. A gum sole two years in reads as a shoe that has been worn, which is the point of the material.

Cleaning the sole

Weekly, or whenever it looks grey rather than amber. Ten minutes.

Dry brush first. A medium-stiff brush across the tread to lift grit and dried mud. Skipping this step grinds the dirt in during the wet stage.
Warm water and a drop of mild soap. Washing-up liquid is fine. Never hot water — heat softens the rubber and can weaken the bond to the midsole.
Scrub the outsole and the sidewall. Work in small circles. Keep the brush on the rubber and off the upper.
Scuff marks: a clean pencil eraser or a melamine sponge, used lightly. Melamine is mildly abrasive — a few passes only, or you will dull the sole's surface.
Wipe with a damp cloth to lift the soap residue, which otherwise attracts fresh dirt.
Air dry away from heat, at room temperature, out of the sun.

What not to do

No bleach or whitening products. They are formulated for white synthetic midsoles and will bleach patches of the gum unevenly. The damage is permanent.
No washing machine. Agitation and heat break down the adhesive at the sole bond. This is the single most common way people destroy a good pair.
No acetone, solvents or petrol-based cleaners. They dissolve natural rubber.
No tumble dryer, hairdryer or radiator. Heat is what makes soles separate and warp.
No aggressive wire brushes. They tear the tread pattern.

Caring for the upper

Suede and nubuck

Never soak it. Brush dry with a suede brush, always in one direction. Lift marks with a suede eraser. Treat with a suede protector spray before the first wear and again every few weeks. Water stains lift better if you dampen the whole panel evenly rather than spot-treating.

Smooth leather

Wipe with a barely damp cloth and mild soap. Dry immediately, then condition every couple of months to stop cracking at the flex point across the toe. Do not let leather dry near heat — it stiffens and cracks.

Canvas

Soft brush with soapy water, then blot with a clean cloth. Stuff the shoe with white paper while drying to hold its shape. Avoid coloured newspaper, which transfers ink.

Mesh and knit

Soft brush only, gently, with diluted soap. Mesh damages easily and will not recover from hard scrubbing. Work from the outside of a stain inward to avoid spreading a ring.

Storage

Keep them in the original box, in a cool dark place.
Use shoe trees or paper stuffing to hold shape and absorb moisture.
Never store a pair damp. Let them dry fully first — 24 hours at room temperature.
Rotate between pairs. A day of rest lets the midsole foam recover and roughly doubles the useful life of both.

Wear versus defect

Worth knowing the difference before you contact us about a fault.

Normal wear, not covered: gum darkening with age, tread wearing down, creasing across the toe box, midsole foam compressing, colour fading on a suede upper from sunlight.

Potential defect, worth reporting: the sole separating from the midsole in normal use, stitching failing along a seam, an eyelet tearing out, a construction fault present from the first wear.

If you think you have the second kind, see the Returns & Refunds page — the EU legal guarantee runs for two years and we honour it.

Questions about a specific pair?

Materials differ, and a treatment that suits smooth leather can ruin suede. If you are unsure what your pair is made of or how to treat a particular mark, send us a photograph through our contact page before you try anything.