She walked over to the workbench and pointed to the massive engine block, split cleanly in half.
"Every mechanic replaced the internal parts, but no one replaced the original crankcase," she explained, shining a flashlight into the heavy metal housing. "Look at the casting. There's a millimeter of variance on the interior wall. It throws off the harmonic balance. As the engine heats up, the metal expands asymmetrically. By third gear, the vibration is so violent it tears the internal components apart."
Stone frowned. "A factory defect?"
"No," Riley said, her heart beating faster. "It was machined this way on purpose. To hide this."
She reached into a specialized groove carved deep into the thickest part of the engine casing. With a pair of needle-nose pliers, she hooked a small metallic ring and pulled.
With a sharp click, a hidden compartment in the heavy iron block slid open. The fifty Hells Angels collectively held their breath.
From the compartment, Riley pulled out a heavy, sealed titanium cylinder, about the size of a cigar tube. It had been resting perfectly in the asymmetrical void, causing the imbalance that ruined the bike.
The President stepped forward, his cold eyes wide. He took the cylinder from Riley's oil-stained hands. With a heavy twist, he unscrewed the cap and slid out a tightly rolled stack of papers and a heavy silver ring.
"I'll be damned," the President whispered. "The founding charter. And the original President's ring. We thought the Feds confiscated this twenty years ago."
The garage erupted into low, reverent murmurs. The founding charter was the holy grail of their chapter, a piece of their history they believed was lost forever.
"The founder hid it in the engine block before he was raided," Stone deduced, staring at the empty crankcase. "He designed the flaw so nobody could ride the bike and discover it. But who the hell had the skill to machine a puzzle box out of a working Harley engine?"
"Only one guy," the President said, his voice thick with emotion. "Our master builder. Guy vanished into the wind fifteen years ago to keep the heat off the club. Best mechanic I ever knew."