Alpina STS2: Why this tubeless system sets the standard in Supermoto

Anyone aiming for the top in Supermoto racing cannot ignore one topic: tubeless systems. But not all spoked wheels are created equal. While many solutions rely on error-prone rim tape or subsequent sealing, Alpina with its patented STS2 system takes a technologically superior approach.

In this article, we'll look at why the heart of this system – the STS nipple – makes the difference between a conventional wheel and a true performance wheel.

The Core: The STS Special Nipples

The secret to Alpina rims lies not in a coating, but in the mechanical construction. The special STS nipples are precisely positioned within the rim profile and perform two tasks simultaneously: they keep the spokes under tension and seal the system absolutely reliably.

1. Sealing with O-rings: Proven in Aviation

Instead of relying on adhesives or rubber bands, Alpina uses high-quality O-rings on the nipple body.

Background: O-rings are the backbone of critical mechanical applications in the automotive and aerospace industries. They are characterized by extreme durability, versatility, and enormous resistance to extreme temperature fluctuations.

Since your motorcycle is already protected in numerous places (engine, gearbox, chassis) by O-rings, Alpina now brings this proven safety directly to your rim. The result: a system that remains airtight even under massive stress on the kart track or during hard off-road jumps.

2. Safety through stainless steel retaining rings

An often underestimated point in racing is break resistance. What happens if a spoke breaks? With conventional systems, a loose nipple in the rim bed could have fatal consequences. Not so with the STS2 system: a special stainless steel retaining ring fixes the nipple. Even in the event of a spoke break, the nipple is not ejected from the rim. This protects the tire from internal damage and allows you, in an emergency, to finish the ride in a controlled manner or reach the nearest workshop safely.

The advantages at a glance: Why STS2?

• No vulcanization, no tape: No sticky residue when changing spokes, no brittle rim tape.
• Weight savings: By eliminating the tube, you significantly reduce rotating masses (up to 250g savings on the rim ring alone).
• Easy maintenance: Spokes can be re-tensioned or replaced like on a normal wheel, without destroying the tubeless system.
• Safety: The stainless steel retainer minimizes consequential damage in case of material fatigue.

Conclusion: The Evolution of the Spoked Wheel

The Alpina STS2 system is not a short-lived trend, but a consistent evolution for riders who demand uncompromising safety and performance. Whether for the Honda CRF 450, Ducati Desmo 450, Husqvarna FS or KTM EXC and SMR - or other Supermoto models – the combination of forged rings and STS2 technology is the ultimate upgrade.

At hartl-racing.de we offer you this system in two variants:

• Collection-Line: Top performance with fast delivery times (approx. 10 working days).
• Made-to-measure-Line: 100% Custom according to your color preferences.