1928 Ace Four Prototype Engine no. DA783
Lot 390
The former property of Mr. E. Paul du Pont,1928 Ace Four "Hemi head" Prototype Sport Solo Engine no. DA783
US$ 200,000 - 250,000
£120,000 - 150,000
amended
Lot Details
The former property of Mr. E. Paul du Pont
1928 Ace Four "Hemi head" Prototype Sport Solo
Engine no. DA783
William Henderson was one of the greatest, possibly the greatest, motorcycle engineer in America's early era of motorcycle innovation. He was the country's supreme enthusiast for the in-line 'Four', and his contribution to the genre exceeded the best made by any comparable European makers during what became the 'Age of the Fours'. Subsequent significant designs came from Honda in the 1960s.

Henderson was successful but low on capital, so the company interests were bought by Ignaz Schwinn , William Henderson later leaving Excelsior to found the ACE Motor Corporation in 1919, re-engineering his original design following recent advances in engine technology. To boost sales, Ace embarked on a series of record-breaking exploits, with the company claiming an astonishing speed at129 mph in 1923. The 'Ace' became every collector's dream.

Following Henderson's early death, the Ace company was later sold, the last 'factory'Ace made in 1929, though not before this machine, 'X-1 28', was likely made for owner Paul Du Pont as a prototype. Unusually, much of this machine was constructed of the light-gauge aluminum then new for aircraft use and surviving components, including the tank (replicated for safety reasons), fenders, 'bars, rims, and other parts, some of which are stamped with this number.

The unique machine, purchased directly by an earlier collector from the Du Pont estate, has now been re-united, expensively, with its presumed unique and original engine, both fitting together exactly as when new with no adjustment needed. The 100ci unit represents the largest-capacity Ace made, with Ricardo 'hemi'cylinders teamed with high-lift cams and large valves. Marque experts have authenticated the rebuild to the original specification - no lights were ever fitted - and this fabulously restored, startlingly 'modern' machine, in its original Duesenberg Blue, is the result. Unique.

Footnotes

  • Sold on a Bill of Sale

Saleroom notices

  • Although the vendor believes that the frame and engine were originally one unit, during the course of our research, we have been unable to substantiate this claim and therefore recommend that you bid accordingly. Parts, including - but not limited to - the aluminum fenders and rims, were newly manufactured, as the originals were deemed unsalvageable.
Activities
Auction information

This auction is now finished.

If you are interested in consigning in future auctions, please email us at motors.us@bonhams.com or request a complimentary motorcycle appraisal.

If you have queries about lots purchased in this auction, please contact customer services.

Buyers' Obligations

ALL BIDDERS MUST AGREE THAT THEY HAVE READ AND UNDERSTOOD BONHAMS' CONDITIONS OF SALE AND AGREE TO BE BOUND BY THEM, AND AGREE TO PAY THE BUYER'S PREMIUM AND ANY OTHER CHARGES MENTIONED IN THE NOTICE TO BIDDERS. THIS AFFECTS THE BIDDERS LEGAL RIGHTS.

If you have any complaints or questions about the Conditions of Sale, please contact your nearest customer services team.

Buyers' Premium and Charges

For all Sales categories excluding Arms & Armor, Coins & Medals, Motor Cars, Motorcycles, and Wine & Whisky:

Buyer's Premium Rates
25% on the first $100,000 of the Hammer Price
20% from $100,001 to $2,000,000 of the Hammer Price
12% on the excess over $2,000,000 of the Hammer Price

Payment Notices

Payment for purchases may be made in or by (a) cash, (b) cashier's check or money order, (c) personal check with approved credit drawn on a U.S. bank, (d) wire transfer or other immediate bank transfer, or (e) Visa, MasterCard, American Express or Discover credit, charge or debit card. A processing fee will be assessed on any returned checks. Please note that the amount of cash notes and cash equivalents that can be accepted from a given purchaser may be limited.

Shipping Notices

For information and estimates on domestic and international shipping as well as export licences please contact Bonhams Shipping Department.

Contacts
  1. Motor Cars (US)
    Auction Administration - Motorcycles
    Bonhams
    Work
    Work +1 415 391 4000
    FaxFax: +1 415 391 4040
  2. Nick Smith
    Specialist - Motorcycles
    Bonhams
    Work
    7601 W. Sunset Boulevard
    Los Angeles, United States 90046
    Work +1 323 436 5470
    FaxFax: +1 323 850 5843