LOT 219
The David Plant Collection, 1931 Sunbeam 500cc Model 9 Project
The David Plant Collection, 1931 Sunbeam 500cc Model 9 Project
The David Plant Collection, 1931 Sunbeam 500cc Model 9 Project
Frame no. D10207
Engine no. LL5739
Sunbeam had begun experimenting with overhead valves on their factory racers in the early 1920s and these duly appeared on production models in 1924. The new '500' sports roadster was known as the Model 9 - the '350' as the Model 8 - while its racing counterpart, which could top 90mph, was accordingly designated the Model 90. The overhead-valve Model 9's frame and cycle parts, which had much in common with those of Sunbeam's larger sidevalve models, evolved slowly. Sunbeam missed the industry's virtually wholesale switch from flat-tank to saddle-tank frames for the 1928 season, and a saddle-tank version of the Model 9 did not appear until September of that year. Changes to the Model 9's engine were confined mainly to its top-end. The early flat-tankers featured a straight-ahead exhaust port, a peculiarity which necessitated the adoption of a bifurcated down-tube. Pushrod enclosure had arrived by 1930 to be followed a couple of years later by partial enclosure of the rocker gear.
On file is a letter to the vendor dated February 1989 from a Mr Tony O'Brian stating "as discussed at the auction I enclose three papers from my late uncle's personal effects relating to an insurance renewal confirming his address and the original registration number of OV 1996 which was registered in Birmingham in 1930/31. The machine was always described as a 500cc Sunbeam Long Stroke". (Mr O'Brian's uncle was William Morgan of Llantilio, Pertholey.) In addition there are three documents on file for insurance dating from April 1950. It should be noted that the registration 'OV 1996' is not in either the DVLA or HPI database, and that there is no registration document with this Lot. Accordingly, prospective purchasers must satisfy themselves with regard to this motorcycle's registration status prior to bidding. A potentially most rewarding restoration project (the engine turns over).
Condition and completeness unknown, Prospective purchasers should satisfy themselves with regard to this motorcycle's completeness, history, authenticity, originality and mechanical condition prior to bidding.
Footnotes
BUYER'S PREMIUM
The Buyer's Premium for this Lot is 28%+VAT on the first £40k of the Hammer Price, then 27%+VAT up to £800k, then 21%+VAT up to £4.5M and 14.5%+VAT thereafter.
All lots are sold 'as is/where is' and Bidders must satisfy themselves as to the provenance, condition, age, completeness and originality prior to bidding.
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