Working an 11 Hour Day at 80 Years Old!

Published on June 17, 2026
Duration: 9:29

This guide details a method for precisely relocating cam holes in a Sportster engine case, a technique developed by Dragon Man over 50 years. It involves using a custom fixture and a dial indicator to accurately find the center of existing holes, followed by drilling and boring to create new holes with a specific interference press fit. This method is presented as an alternative to using blueprints for complex engine modifications.

Quick Summary

Dragon Man, a gunsmith with 50 years of experience, demonstrates an expert method for relocating cam holes in Harley-Davidson Sportster engines. This technique utilizes a custom fixture and a dial indicator to precisely locate and bore new holes, creating a 3-4 thousandths interference press fit, offering a practical alternative to blueprints for complex engine modifications.

Chapters

  1. 00:00Introduction & Fixture Creation
  2. 00:35Relocating Sportster Cam Holes
  3. 01:08Shaving & Balancing Flywheels
  4. 02:10Motor Preparation & Break-in
  5. 02:51Lower End Rebuild Process
  6. 03:28Engine & Transmission Work
  7. 04:09Rebuild Your Own Motor Service
  8. 05:02Dragon Man's Attack Jeep & Museum
  9. 05:41Contact Information & Museum Tours

Frequently Asked Questions

How can I accurately relocate cam holes in a Harley-Davidson Sportster engine case?

You can accurately relocate cam holes by creating a custom fixture that aligns with the original hole positions. Then, use a dial indicator to find the precise center of each hole on the engine case. After locking the machine table, drill and bore out the new holes to achieve a specific interference press fit, typically three to four thousandths.

What is the purpose of shaving flywheels on a motorcycle engine?

Shaving flywheels reduces their weight, which allows the engine to achieve higher RPMs more quickly. This modification significantly improves throttle response, making the motorcycle feel more agile and responsive when accelerating.

What does the 'Rebuild Your Own Motor' service from Dragon Man include?

The 'Rebuild Your Own Motor' service provides customers with a fully rebuilt engine kit, including gaskets, new pistons, rings, pins, and locks. It allows customers to inspect all the work performed, measure components like piston-to-wall clearance and ring gap, and even prime the oil system before final assembly.

How long has Dragon Man been performing custom engine work?

Dragon Man has been performing custom engine work, including techniques like relocating cam holes, for nearly 50 years. His extensive experience and developed methods ensure reliable and effective modifications for various motorcycle engines.

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