Bicycle Truing Stand – Preciray Type B

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Bicycle Truing Stand Preciray Type B

Synonyms: DE:Fahhrad Zentrierstäder
Location: Bike Lounge

Wheel Truing Stand – Preciray (Type B)

Overview

The Preciray Type B is an extremely robust, heavy-duty professional wheel truing stand built for continuous workshop use. This tool was specifically designed for high-volume wheel building, truing, and straightening in bicycle factories, frame builder workshops, and racing teams. Its defining feature is a purely mechanical needle gauge that displays lateral and radial runout simultaneously with a significant magnification.

Technical Specifications & Features

  • Manufacturer: Ateliers J. Martin (Belgium), historically also distributed via VAR (France).
  • Weight: Approx. 25 kg (solid cast iron/steel construction for absolute stability and zero vibration).
  • Design: Vertical, synchronously adjustable support arms to accommodate different hub widths.
  • Measurement Principle: Purely mechanical via roller feelers and lever linkages (no failure-prone electronics).

How It Works & Key Features

Unlike modern standard truing stands, where the mechanic visually checks the rim against scraping edges or reads dial indicators, the Preciray utilizes a unique, analog needle display system.

  1. Simultaneous Measurement: Two ball-bearing roller feelers run directly on the rim shoulder (therefore, it is ideally used on bare rims without tires installed).
  2. Mechanical Leverage: The rollers transfer the slightest imperfections through a lever mechanism to two delicate indicator needles on a front-facing scale. The movement is mechanically amplified by approximately three times (3x).
  3. Truing While Seated: The mechanic typically sits in front of the stand and looks down onto the display panel. Spinning the wheel instantly shows how lateral runout (right needle) and radial runout (left needle) change in sync.
  4. Automatic Centering (Dishing): Thanks to the synchronous adjustment of the support arms, the wheel is automatically perfectly centered relative to the hub axle when clamped. This makes a separate dishing tool unnecessary in most cases.

Advantages and Disadvantages in Modern Workshop Use

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Advantages Disadvantages / Limitations
  • Extreme Durability: Engineered for decades of industrial-grade heavy use.
  • Incredible Precision: The 3x mechanical amplification makes even the most minor nuances instantly visible.
  • Ergonomics: Reading the needles is significantly easier on the eyes during long shifts compared to staring at tiny gaps.
  • Time-Consuming with Tires: Since the roller feelers require a clean rim shoulder, quick touch-ups on wheels with tires inflated are more cumbersome.
  • Axle Standards: Originally optimized for classic quick-releases and solid threaded axles. Modern thru-axles (Boost standard) require special axle adapters.
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