Heidenau K 37 3.25-18 Enduro Rear Motorcycle Tyre

The Heidenau K 37 3.25-18 is a German-made enduro rear motorcycle tyre built for 18-inch rims. It fits classic and off-road machines such as MZ, Jawa, Simson, IZH, Ural and Dnepr. In addition, it suits older Japanese and European enduro models running the same rim diameter. The tyre carries a block-pattern enduro tread designed for mixed surfaces.

Construction is diagonal, also known as bias-ply. The casing is marked TT (TubeType), so the tyre runs with an inner tube only. Load index is 59 (243 kg) and the speed rating is P (up to 150 km/h). Each tyre weighs 5.01 kg.

The 3.25-18 marking describes roughly 3.25 inches of section width on an 18-inch rim. Moreover, the dash in that code signals diagonal rather than radial construction. K 37 is the tread profile designation, not a size. Production takes place in Germany.

Key Benefits and Advantages

• Enduro block tread – the blocky pattern grips reliably on gravel, dirt and mixed surfaces.
• Diagonal construction – the cross-ply carcass absorbs impacts and loads better off-road.
• TT / TubeType casing – built for tube use, so it stays dependable on rough, potholed roads.
• Load index 59 – a single tyre carries up to 243 kg.
• Speed rating P – certified for speeds up to 150 km/h.
• Weight of 5.01 kg – a sturdy carcass without surplus mass on the wheel.
• Classic 3.25-18 size – matches 18-inch rims measured in the older inch system.
• Made in Germany – Heidenau production delivers consistent quality and long service life.

Who Is This Tyre For?

This rear tyre suits motorcycles with an 18-inch rear rim that need a 3.25-inch section width. Above all, that covers classic and Eastern European machines: MZ, Jawa, Simson, IZH, Ural and Dnepr. It also fits older Japanese and European enduro motorcycles with the same rim size.

The K 37 is aimed at riders who cover mixed surfaces. Gravel tracks, forest roads and dirt sections all fall within its remit. Between those stretches, the tread keeps handling predictable on tarmac. As a result, it works for everyday riding as well as longer trips.

Important: this tyre mounts with an inner tube only. Therefore it is not suitable for tubeless (TL) systems. The inner tube is purchased separately.

Package Contents

• 1 × Heidenau K 37 3.25-18 rear motorcycle tyre
• Inner tube not included – order separately

Technical Specifications

Why Choose the Heidenau K 37 3.25-18?

Heidenau is a German tyre maker based in the town of Heidenau, Saxony. The company has produced tyres since 1946. Its focus covers motorcycles, scooters, mopeds, sidecars and classic machines.

Unlike most manufacturers, Heidenau still produces the old inch sizes, including 3.25-18. Consequently, owners of classic motorcycles receive a freshly built tyre rather than aged warehouse stock. That matters on bikes where correct period sizing is hard to source.

The diagonal carcass here is a deliberate choice. It flexes more responsively over impacts than a radial casing. For that reason, riding stays composed off-road and on poor road surfaces.

Frequently Asked Questions

Is the Heidenau K 37 3.25-18 a front or rear tyre?

• This version is specified as a rear tyre.
• The tyre profile is K 37 and the type is enduro.
• The K 37 tread pattern is produced for both front and rear positions.

Can the Heidenau K 37 3.25-18 be fitted without an inner tube?

• No. The casing is marked TT (TubeType).
• TT means the tyre is used with an inner tube only.
• The tube is not included and is bought separately.

Which motorcycles does the Heidenau K 37 3.25-18 fit?

• Machines with an 18-inch rear rim taking a 3.25-inch section width.
• Classic and Eastern European models: MZ, Jawa, Simson, IZH, Ural and Dnepr.
• Older Japanese and European enduro models with the same rim size.

Does the Heidenau K 37 fit a Simson or Jawa?

• Yes, provided the rear rim is 18 inches and accepts a 3.25 profile width.
• The same applies to MZ, IZH, Ural and Dnepr motorcycles.
• Always check the rim diameter stamped on your wheel before ordering.

What does the 3.25-18 marking mean?

• 3.25 is the approximate section width in inches.
• 18 is the rim diameter in inches.
• The dash indicates diagonal construction rather than radial.

How much load and speed can this tyre handle?

• Load index 59 corresponds to 243 kg per tyre.
• Speed rating P certifies the tyre up to 150 km/h.
• Tyre weight is 5.01 kg.

Is this tyre usable on tarmac as well as off-road?

• The block tread is designed for mixed surfaces.
• It grips on gravel, dirt and forest roads.
• On tarmac, handling remains predictable between off-road sections.

Where is the Heidenau K 37 made?

• Production takes place in Germany (DE).
• Heidenau has manufactured tyres since 1946 in Saxony.
• One tyre is supplied per unit.

The Heidenau K 37 3.25-18 pairs a blocky enduro tread with a cross-ply TubeType carcass rated at 243 kg and 150 km/h. For an MZ, Jawa, Simson, IZH, Ural or Dnepr running an 18-inch rear rim, it restores correct period sizing with current German production. Remember to order an inner tube alongside it.