Heidenau K37 3.50-18 62P RF TT

Heidenau K37 3.50-18 62P is a classic block-pattern tyre that keeps the spirit of an old machine and sits on 1960s–80s restorations and custom builds like it belongs there. It handles tarmac as well as light-to-moderate dirt, yet it is built with modern tyre technology. The 3.50-18 fits classic bikes and scramblers in tube-type (TT) form — and looks as though it left the factory on the bike.

What K37 gives you

• Period-correct looks: The classic block tread of Heidenau K37 looks native on old iron — none of that modern "plastic" clash.
• Grip on dirt: Big blocks with wide gaps bite into earth, grass and sand. Heidenau K37 rides on happily where the tarmac ends — within reason.
• Reinforced carcass (RF): Heidenau K37 comes in a reinforced build. The sidewall takes the hit on potholes rather than folding on the first bump.
• Kind to an old chassis: The bias carcass and tall profile of Heidenau K37 soak up bumps — just what a bike needs when its fork and swingarm are past their prime.

Rubber and carcass

Heidenau K37 uses a bias-ply construction in tube-type (TT) form with a reinforced (RF) carcass. The block tread sheds mud off-road on its own, and on tarmac it stays predictable and does not squirm through corners. The compound is chosen so it grips on dirt yet does not wear out over a single season on the road.

Which bikes usually take the 3.50-18 size

The 3.50-18 (TT) is a familiar fitment for classic bikes, scramblers and old dual-sports of the 1960s–80s, plus customs built on them. Heidenau K37 in this size usually goes on the rear, on machines of roughly 125–500 cc. Treat this as a guide to the class of bike, not a guarantee — check the axle and fitment against your manual.

Where K37 is not the best pick

Heidenau K37 is a "road plus moderate dirt" tyre, and no illusions: for hard enduro and mud racing, take a dedicated off-road tyre, and for fast road bikes, road models with a higher speed rating. Heidenau K37 is strong elsewhere — in its classic looks and calm manners on mixed roads.

Who it suits

Heidenau K37 3.50-18 is for restorations and customs: an old bike for everyday use, town, the country and light dirt. For those who value an authentic look and would rather not swap tyres for every puddle. Choose your size and order K37 with delivery across Kazakhstan — the full range of Heidenau road-and-trail tyres is here.