He rolled the motorcycle onto the lift and began with the basics Aaron had insisted were never beneath a good mechanic. He checked the ignition components and verified that the plugs told a consistent story. He measured compression, inspected fuel delivery for obvious restrictions, and examined the fresh harness for poor connections or damage. He found a motorcycle that seemed, on the surface, healthy enough to make every expert who had worked on it look reasonable.
At two twenty, his phone rang. Ms. Alvarez was calling from the bank, and Caleb answered with the cautious tone he used for people who controlled outcomes he could not afford to ignore. She asked whether he had reviewed the documents she had sent and reminded him of the upcoming deadline. He told her he was working on a job that might give him a way to pay, then immediately regretted making possibility sound like progress.
'Caleb, I hope the job comes through,' she said. 'But please remember what we discussed. Don't promise the bank money that isn't in your account, and don't gamble your safety to save a building.'
He looked at the enormous red motorcycle balanced on the lift. 'Yes, ma'am,' he said, and ended the call.
By three, sweat had darkened his shirt from the collar to the belt. He drank lukewarm water from a plastic bottle and forced himself to sit for five minutes beside the fan. The shop smelled of hot metal and the sharp cleaner he had used on the engine cases. He could hear Aaron telling him to slow down before his hands outpaced his brain, and for once he obeyed.
He reviewed his notes. The failure appeared only under a very narrow combination of load and speed, and it affected the machine's handling as well as the engine. A simple ignition problem might explain the engine shutting off, but it did not comfortably explain the shudder Grip had described as coming through the frame. A purely mechanical frame problem could explain handling trouble, but not necessarily the sudden ignition failure.
Two symptoms, he wrote. One event. Which is the cause?
He stepped toward the old dynamometer, a hulking machine Aaron had bought from a closing repair business in the early 1990s. The rollers and control unit occupied half a bay, and the equipment had outlived several attempts to replace it with something easier to maintain. Aaron had taught Caleb to respect it because stationary testing could produce dangerous forces even when a motorcycle never moved an inch down the road. Caleb inspected the restraints, set up barriers, and decided he would not put himself or anyone else in line with the moving machinery.
At three thirty, the Knucklehead was positioned on the test rig. Caleb checked his notes, checked the restraints again, and looked at the shop door as if Aaron might walk through it to approve his preparations. Then he started the engine. Its uneven idle settled into a full, satisfying rhythm that filled every corner of the room.