
LOT 313 N
1939 Cotton-JAP 500cc Special Registration no. Not registered Frame no. None visible Engine no. KOZ/O 64232 SJ
Sold for £12,075 inc. premium
Lot 313N
1939 Cotton-JAP 500cc Special Registration no. Not registered Frame no. None visible Engine no. KOZ/O 64232 SJ
The Autumn Stafford Sale: The Classic Motorcycle Mechanics Show|20 October 2019, 11:00 BST|Stafford, Staffordshire County Showground
1939 Cotton-JAP 500cc Special
Registration no. Not registered
Frame no. None visible
Engine no. KOZ/O 64232 SJ
Registration no. Not registered
Frame no. None visible
Engine no. KOZ/O 64232 SJ
Gloucester-based Cotton established its reputation with a string of racing successes in the 1920s thanks to an innovative frame patented by Frank Willoughby Cotton. Cotton's design featured four straight tubes running from the steering head to the rear wheel spindle, augmented by straight stays supporting the gearbox and engine. The result was a stiff, lightweight chassis vastly superior to the bicycle-derived frame used by the majority of manufacturers. Cotton relied on proprietary engines, but such was the advantage conferred by its frame that the Cotton had little trouble seeing off similarly powered rivals.
We are advised that this machine's previous owner was Les Martin of Douglas, Isle of Man, a regular TT competitor from 1933 to 1949 mostly riding Cotton's in the Lightweight races, his best result was 4th place in the 1939 Lightweight race riding an Excelsior. The machine was described as 'restored' when purchased in 1985, since when it has been stored and used only for a solitary Vintage run in which it performed faultlessly. Noteworthy features include a Wal Phillips fuel injector, 'sports' camshaft, and 'The Celestrial Express' script to the fuel tank. The engine number pre/suffixes suggest this 490cc ohv dry-sump unit (manufactured some time between 1 Sep 1937 and 31 August 1938) was a special 'customer order' as indicated by the 'S' suffix and would have benefited from either a 'Modified inlet port 500cc' or 'Piston ring thickness altered', as indicated by the 'J' suffix. Last run in March 2019, the machine is offered with an old-style continuation logbook (issued 1969) for the VRN DFG 687 (no longer assigned to the motorcycle) and assorted photocopies of Cotton-related literature.
We are advised that this machine's previous owner was Les Martin of Douglas, Isle of Man, a regular TT competitor from 1933 to 1949 mostly riding Cotton's in the Lightweight races, his best result was 4th place in the 1939 Lightweight race riding an Excelsior. The machine was described as 'restored' when purchased in 1985, since when it has been stored and used only for a solitary Vintage run in which it performed faultlessly. Noteworthy features include a Wal Phillips fuel injector, 'sports' camshaft, and 'The Celestrial Express' script to the fuel tank. The engine number pre/suffixes suggest this 490cc ohv dry-sump unit (manufactured some time between 1 Sep 1937 and 31 August 1938) was a special 'customer order' as indicated by the 'S' suffix and would have benefited from either a 'Modified inlet port 500cc' or 'Piston ring thickness altered', as indicated by the 'J' suffix. Last run in March 2019, the machine is offered with an old-style continuation logbook (issued 1969) for the VRN DFG 687 (no longer assigned to the motorcycle) and assorted photocopies of Cotton-related literature.
Footnotes
As with all Lots in the Sale, this Lot is 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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Auction Viewings
- 19 October 2019, 09:00 - 17:00 BST
- 20 October 2019, 09:00 - 17:00 BST
Lot symbols
| N | NOVA declaration |
| If purchased by a UK resident, this machine is subject to a NOVA declaration, whilst the responsibility of submitting the NOVA rests with the Buyer to do so, Bonhams will facilitate the process by engaging an agent (SHIPPIO) to undertake the NOVA and C88 (customs) application if applicable on the Buyer's behalf. A fee of £350 + VAT to do so will be added to the Buyer's invoice. |
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