Friday, April 8, 2011

Alpha centuri

Alpha Bearings of Dudley is an engineering company that manufactures parts for engines, still in business today. In the early 1960's the small but powerful Villiers 197cc engine was being used for racing. As more and more power was extracted from it (they got to around 30 bhp!) stock parts kept on failing. Alpha stepped up to the plate supplying better parts. This eventually led them to decide to produce entire engines, called "Centuri" (there is little information out there and I'm not sure if this is a typo or not). Alpha was part of the E H & P Smith conglomerate that owned, among other companies, Royal Enfield and Albion Gearboxes at that time. Due to this relation the Alpha Centuri was fitted into an Enfield frame, as shown in the picture. Apparently Royal Enfield was not happy about this. They eventually settled for a GP5 frame, but Royal Enfield demanded that the frame not be modified, which lead to a sub-optimal placement of the engine. With the demise of Royal Enfield's own racing effort, Starr engineering got the dynamometer that had been used to tune the GP5. With a Centuri engine and a new frame, reminiscent of the GP5, Hadley, an unpaid helper at Alpha collaborated with Starr and continued development. The bike proved fast but fragile, and the Albion gearbox with its false neutrals proved a hindrance. Eventually the project was canceled in 1968 by E H & P Smith who decided to pull out of racing entirely. Read about recent attempts to restore a Centuri here.


  1. Hi Jorge
    Your picture is not a Centuri engined Enfield, but an Alpha peripheral valve engine in an Enfield. Alpha provided a number of this type of engines to Royal Enfield for evaluation, but this idea died along with many others. The good news is the engine out of that bike is still around, but not running although parts of it were running in another Enfield frame a GP5 version until about 5 years ago. The GP5 is still running but now with a replica GP5 engine fitted.

  2. bad link, please use
    instead of Lortim URL
    BHR Festival in June 2016 saw 5 Centuri in a row



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