Duncan Racing offers complete In-House machine services to accommodate their complete 2 & 4 Stroke ATV and UTV Engine Building Services. DR services include.

  • Cylinder Boring and Honing

  • Crankshaft Rebuilding

  • Cylinder Resleeving

  • Flywheel Machining/Lightening

  • Stud  and Tread Repair

  • Serdi 4-Stroke valve Seat Machining

  • Big Valve Installation

  • Seat installation

  • 2 & 4 Stroke Port Modifications

  • Case Boring

  • Carburetor Boring and DR Super Flow Mods

  • Case Welding and Repair

DR also offers the above service on individual components. Ship parts to DR-DR will perform required modifications and ship back. Include DR Work Order Form will ALL parts shipped to DR.

DR carries a full line of parts to complete machine shop services including; OEM Parts, pistons, valves, guides, springs, rods,bearings, gaskets, studs, jets/needles etc.

Contact Duncan Racing for more information phone 619.258.6306 , email

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