Chapter 11 Exercise 21

21. Assuming the salaries and capital costs are fixed to start Rolling Thunder Bicycles, and assuming the average price of a bicycle is $2,250, compute the break-even number of bicycles.

The result is in the C11Ex25.xlsx spreadsheet in the Breakeven worksheet. Quantity is incremented by 100, you could use 50 to get finer detail. Depending on which fixed costs you include (salary, fixtures, marketing, lease, depreciation), the breakeven point will change slightly. But somewhere between 800 and 900 bicycles seems reasonable.
Breakeven chart