1930 Brough Superior SS100 Alpine Grand Sports

“Rolls-Royce of Motorcycles” is brochure weather. A 1930 Brough Superior SS100 Alpine Grand Sports with a Works Record Card, matching major numbers, and Bentley & Draper sprung frame is a countable object. Bonhams’ Autumn Stafford catalogue places this machine among the 21 JAP-engined SS100s built for 1930 — Path A scarcity you can cite without special pleading. Alpine Grand Sports specification (lower compression touring brief, fly-screen and toolbox language in the model’s period identity) plus B&D springing separates it from a generic rigid SS100 story.

Identity as published: frame S. 1015, tank 2099, engine JTO/W 84303/CS, gearbox 169940. Catalog diligence notes matching registration/frame/engine/tank with a non-original gearbox — we repeat that honesty rather than smooth it. The Copy Works Record Card shows dispatch with a Cruiser sidecar to Sears Garage. Later public trail: Shoosmith’s Gangbridge Collection auction 1989, Eddy Shah ownership oriented around the MY 2654 plate, Vaughan Gaskell’s 1998 recognition and purchase, then a Dave Clark restoration from 1999 into the early 2000s. Since Gaskell’s death in 2019 the SS100 has remained in family hands. That is collector-provenance continuity, not a factory championship diary.

Brooklands gets a hard editorial line. The catalogue says the machine is reputed to have raced there (foot-change suggestion) and that the claim has never been conclusively verified. Rare Machines will not launder “reputed Brooklands” into Ultra provenance. The score treats verified works paperwork and matching majors as the spine; unverified track lore as color with a haircut.

Score 87 — Rare-enough. Production points reflect 1-of-21 JAP SS100s for 1930 with AGS/B&D specificity; specification is correct Alpine Grand Sports sprung-frame iron; provenance is strong on collector and restore trail, capped because Brooklands remains unverified; documentation is Works Record Card plus Bonhams file depth; market appearances of sorted 1930 JAP SS100 AGS machines are infrequent; condition credits the Clark restoration presentation without inventing unrestored patina. Diversifies the Live moto board off Honda/Yamaha works GP iron.

Status: Live catalog — Bonhams Stafford Lot 328, 11 October 2026. Re-verify before newsletter send.

Watcher’s checklist

1. Match frame S. 1015 / engine JTO/W 84303/CS / tank 2099 to the Works Record Card copies.
2. Budget for the catalogued non-original gearbox.
3. Separate verified ownership trail from unverified Brooklands reputation.
4. Review Dave Clark restoration notes and what was replaced vs retained.
5. Confirm UK registration MY 2654 recovery paperwork if plate continuity matters to you.
6. Re-check Bonhams Lot 328 status before you act.