In 1909, the four Stevens brothers, Harry, George, Joe, and Jack acquired the Retreat premises to manufacture motorcycles. They had recently founded a new company called A. J. Stevens & Company Limited and began to manufacture motorcycles under the name of A.J.S. The machines were extremely successful and orders flooded in. By 1915 larger premises were essential and the brothers purchased Graiseley House, and the surrounding land on which to build a new factory. They left Retreat Street in 1917

The original house and workshops of the Cylindrical Bolt and Lock Works at Retreat Street are clearly shown on the 1903 OS map, so the larger building occupied by A.J.S. in 1909 must have been built some time after 1902, when the 1903 map was updated.

The earliest photo of the Retreat Street Works in 1913 is courtesy of Ray Jones , that photo and the other content here are from Bev Parker's Wolverhampton History website with his permission. 

Plans of the Retreat Street works made in 2009:

Retreat Road site in 2016 - images from Google:

The New Factory at Graiseley Hill 

Near to Retreat Street, on the corner of Graiseley Hill and the Penn Road was Graiseley House, which had a large piece of land attached. 

A.J.S. purchased the house and grounds, and built a new 260ft x 80ft factory.The building was completed in 1915, and production soon moved to Graiseley Hill. The Retreat Street premises were initially used as the company office and repair department.

On 5th November, 1917 the office was transferred into Graiseley House and the repair department moved to the new works.

The Retreat Street buildings were then handed-over to Joe Stevens (senior), who ran the Stevens Screw Company.

After the war, work on enlarging the new factory soon began. Early in 1919 work started on constructing three new buildings, each of which was about the same size as the first building. By the end of 1919 the works covered 109,600sq. ft.

The buildings were laid out to give a smooth flow of material from the goods receiving department at the north side of the site, to the despatch department at the southern end. The original building became the main machine shop, with the machines operated from overhead line shafting. Building work continued, and by the autumn of 1922 the factory covered almost 167,000sq. ft., growing to almost 230,000sq. ft. by 1924.

Plan of the Graiseley Hill site from the auction catalogue in 1932: 

and how the same site appeared in 2016 on Googlemaps:

Sadly sales fell in the late 1920s due to the recession, and the company went into voluntary liquidation on 2nd October 1931. The premises were demolished some years later and a Waitrose supermarket is now on the Graiseley Hill site.