I've used Evergreen Bikes & Lawn Equipment for several bike and lawn equipment repairs. Every time I have visited, the employees have been very helpful in attempting to give an estimate that is usually fairly accurate. After having one bike repaired, the chain was still having problems and they fixed it for no additional charge.
The minimum charge is around $20, and repairs are handled by the hour. There is also a wide range of bikes and lawn equipment that can be purchased.