Thunder Beetle - 1982 Specialized Stumpjumper Electric Conversion

Built in memory of Joseph "Joe" Ferguson (1949-2021), wildlife biologist, craftsman, and builder of many bicycles. This first-year Stumpjumper has migrated west, trading Montana's mountain trails for city streets and still carrying Joe's spirit of adventure.

The Build:
This first-production-year Stumpjumper has been carefully electrified with a Grin Technologies All-Axle rear hub system, transforming a piece of mountain bike history into a capable daily commuter while maintaining the bike's classic lines.

Motor & Drivetrain:
Grin V3 Rear All-Axle SuperH Hub Motor with Statorade cooling injection
135mm QR slotted dropout adapters
7-speed 11-32T cassette
Custom 26" wheel build: Alex DM24 rim, 32h, Sapim Strong 13-14g butted spokes (silver)

Electronics:
Phaserunner L10 V6 controller (silver) with external heatsink
48V 10Ah bottle battery
Mini OLED display with Main9 Superharness
Dyol bidirectional throttle (right-side)