Dangers of Two-wheeled Zipline trolleys

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  • Reliability with Springs & Trolleys

    Reduce your liability with the safest zipline braking system for over 20-years.

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Momentum Engineering LLC

In 2016, zipline expert witness Troy Richardson designed and built a 3 -pound passive/autobraking trolley and telescoping springs. Patterned after the 2002 Park City Mountain Resort (PCMR) zipline he built. PCMR is Accident-Free. Mr. Richardson received his third and fourth US Patents for his Trolleys.

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  • Mike Holder

    "Our company American Adventure Park Systems needed a custom 2.25-inch diameter spring system. Momentum Engineering, LLC's Design Engineer, Troy Richardson developed a Barrel/Telescoping spring to meet our needs this year. Coming soon is our collaborated efforts with Troy on a new US Patent a new stackable spring array dampening system" 

    American Adventure Park Systems 
  • Keith Jacobs

    "Momentum Engineering, LLC provided our camps and the US Military with Barrel/Telescoping springs. They are simple to install, easy to inspect, and last up to 200,000 cycles. We are grateful to find a retailer who sells Zipline Emergency Brakes!" 

    Experiential Systems Inc, 
  • Ken M.

    "Troy's passive braking trolleys and barrel spring systems are excellent for any zip line. In November 2021, I witnessed that heavier 275-lb weights stop about 2-feet shorter than 15-lb weights, I have been in the harness business for almost three decades and Troy's products will reduce your zipline liability!"

  • Experimental Systems

    Lansing, Illinois, USA

    Experiential Systems 
  • American Adventure Parks

    Cartersville, Georgia, USA

  • TouchCloud Global

    Mona Vale, NSM, Australia

How our Springs Work

20 Years of Experience as an Expert Witness

Troy’s knowledge of ASTM, PRCA, ANSI, and ACCT standards will improve purchasing experience. His degrees in Design Engineering and hard work gaining over 30 physics semester hours, 6+ US patents, Designing and building ziplines for 22+years elevates his engineering company and expert witness practice making him a world-class zipline expert. He helps both defendants and plaintiffs serving on both sides. A formidable opponent with successful resolutions to back his reputation, he ensures clients have a path to success before taking a case. His record of success in over 95% successful outcomes in about 30 US states.

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  • Bumper Spacer

    Regular price From $175.00 USD
    Regular price Sale price From $175.00 USD
    Bumper Spacer
  • Auto-Braking Test Trolley

    Regular price From $325.00 USD
    Regular price $595.00 USD Sale price From $325.00 USD
    Auto-Braking Test Trolley