1921 Indian 7hp Powerplus
Lot 14
c.1921 Indian 7hp Powerplus Frame no. 87K579 Engine no. 72S428
£16,000 - 20,000
US$ 27,000 - 34,000
Lot Details
c.1921 Indian 7hp Powerplus
Registration no. CD 4117
Frame no. 87K579
Engine no. 72S428
Competition between the major American motorcycle manufacturers was fierce in the 20th Century's opening decades, a factor that greatly accelerated technological development. In Indian's case, the need to stay ahead of rivals Excelsior and Harley-Davidson prompted the introduction of an eight-valve v-twin racer in 1911, and then in 1916 a new 1,000cc 'flat head' (sidevalve) v-twin - the Powerplus - was introduced to replace the production 'F-head' (inlet over exhaust) type.

Development of the Powerplus had been initiated after Harley-Davidson trounced Indian in the 300-mile Venice road race in the spring of 1915, chief designer Charles Gustafson suggesting that a well-designed sidevalve ought to prove good enough to beat the Harleys. The 42-degree v-twin configuration of the existing Oscar Hedstrom-designed F-head engine was retained, but with side valves and increased use of roller bearings. Gustafson's intuition did indeed prove correct, the new 61ci (990cc) twin proving more powerful than its predecessor right from the start, hence the 'Powerplus' name.

As part of the testing programme prior to Powerplus introduction, works rider Erwin 'Cannonball' Baker rode a pre-production model from Vancouver, Canada to Tijuana, Mexico - an event known as the 'Three Flags' - in August 1915, travelling 1,655 miles in 3 days, 9 hours and 15 minutes, breaking the existing record and emphatically demonstrating the new design's speed and durability.

Indian motorcycles did not have frame numbers until 1931, although many frames have had numbers stamped on them subsequently to facilitate sale and registration. Thus '87K579' would never have been stamped on this machine's frame in period, and if interpreted as an engine number, would date from 1918. The engine dates from 1921. 'CD 4117' was used regularly by the previous owner up to 1960 and then placed in storage, remaining there until it was acquired by the current owner in August 2009. Left un-restored to retain its delightful 'oily rag' patina, the Powerplus is presented in running order and was last MoT'd to 27th May 2013 (MoTs are no longer required for pre-1960 motorcycles). The machine benefits from new chains, new inner tubes and a few new spokes, while the magneto and carburettor were overhauled recently, the latter at a cost of £180. It should be noted that the clutch has been converted to hand operation and the throttle twist-grip moved to the conventional position on the right-side handlebar, thus making life easier for those unfamiliar with Indian's idiosyncrasies. An ideal 'Banbury' machine, this well-preserved Powerplus is offered with current road fund licence and Swansea V5C document.
  1. James Stensel
    Specialist - Motorcycles
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