Testing Motors on a Snow Day

Published on January 25, 2026
Duration: 5:27

This video details the complex process of rebuilding and enhancing motorcycle engines, specifically focusing on Shovelhead models. Dragonman, an expert in machining, explains flywheel modifications for increased RPMs, head work including dual spark plug installations, and critical camshaft specifications. He also outlines pricing for various levels of engine rebuild services, showcasing the extensive capabilities of his machine shop which serves clients nationwide.

Quick Summary

Dragonman's machine shop offers engine rebuild services starting at $1,200 for a basic rebuild with gaskets. A complete motor assembly costs $1,700, and a fully run and tuned motor on a stand is priced at $1,800. These services include expert machining like flywheel weight reduction and dual spark plug head modifications.

Chapters

  1. 00:00Introduction: Shovelhead Motor Build
  2. 00:48Flywheel Machining for Higher RPMs
  3. 01:54Engine Rebuild Service Pricing
  4. 02:53Head Work: Dual Spark Plug Modification
  5. 03:42Shaved Flywheels & Cam Specs Explained
  6. 04:55Contact Info & Shop Location

Frequently Asked Questions

What are the different pricing tiers for engine rebuild services offered?

Dragonman offers three tiers for engine rebuilds: a basic rebuild with gaskets for $1,200, a complete motor assembly for $1,700, and a fully run and tuned motor on a stand for $1,800. These prices reflect the scope of work involved in each service level.

How does flywheel machining affect engine performance?

Machining flywheels to reduce their weight, typically by about 2.5 pounds, decreases rotational mass. This modification allows the engine to rev up faster, improving throttle response and overall acceleration.

What spark plug recommendation is given for dual spark plug cylinder heads?

For cylinder heads modified to accept dual spark plugs, Champion JHH8 spark plugs are specifically recommended. This choice helps ensure there is no interference with the piston during its upward travel.

What is the threshold for upgrading valve springs when modifying camshafts?

When installing camshafts with a lift exceeding .450 inches, it is crucial to upgrade the valve springs. Using stock springs with higher lift cams can lead to valve float or damage.

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