c.1980 Bakker-Yamaha TZ500 Grand Prix Racing Motorcycle Frame no. 01419

c.1980 Bakker-Yamaha TZ500 Grand Prix Racing Motorcycle Frame no. 01419 Please kindly note that this motorbike will be available for viewing by prior appointment in Dortmund: please contact eva.lengler@bonhams.com for booking. World Champion in the 500cc class for Yamaha in 1978, '79 and '80, Kenny Roberts during the latter season had occasionally used the OW48R, a version of the 1979 OW48 fitted with reversed outer cylinders, an arrangement that produced an extra 7bhp. The 1980 season was also notable for the first appearance of a customer version of Yamaha's Grand Prix 500: the TZ500G, which was based on the 1978/79 works bikes. Only detail changes were made to the following year's TZ500H. With their across-the-frame four reaching the end of its development, Yamaha introduced the OW48R's reversed outer cylinders on the customer TZ500J of 1982, though the engine was housed in a conventional tubular steel frame rather than the aluminium one tried occasionally on the works bikes. This would be Yamaha's last customer '500' offered to privateers until 1992, when YZR v-four engines were made available in Harris and ROC chassis. The 1970s/early 1980s was a period when Japanese manufacturers' frame designs lagged behind those of their engines, leading to a healthy market for chassis produced by independent specialists, one of the foremost being Nico Bakker. A successful motorcycle racer, Dutchman Nico Bakker turned to frame-making in the early 1970s, rising to become one of the most highly respected specialists in this field. Catering at first exclusively for the racing fraternity (supplying frames to the likes of Phil Read, Johnny Cecotto, Giacomo Agostini, Kork Ballington and Jack Middleburg among others), Bakker branched out into providing frame kits to accommodate Japanese four-cylinder motors and the six-cylinder Honda CBX. Unfortunately, nothing is known of this Bakker-Yamaha's history apart from what may be deduced from the limited accompanying paperwork (hand-written in German, apparently a receipt). The engine turns over. Key not required Footnotes: Please kindly note that VAT at the prevailing german rate (currently 19%) will be added to the buyer's premium which will be invoiced on a VAT exclusive basis. If you are planning to export, please make the department aware. Saleroom notices: It is possible that this motorcycles engine is not a TZ 500 but rather a TZ 750, which may or may not have been fitted with 250 cylinders, thereby reducing its capacity to 500cc. The TZ 500, in all three versions, featured individual cylinders and heads, whereas the TZ 750 was equipped with two blocks of two cylinders, initially producing 700cc and later the full 750cc. While it was common practice 'in the period' to reduce the capacity to 500cc - potentially the case with this motorcycle - such a modification would typically be accompanied by yellow racing number boards, not the white ones seen fitted, which are indicative of a 750-class machine. Accordingly prospective bidders must satisfy themselves as to the provenance, condition, age, completeness, capacity, compatibility and originality of this machines component parts prior to bidding. Lot to be sold without reserve. For further information on this lot please visit Bonhams.com For further information about this lot please visit the lot listing

Saleroom Notice:
It is possible that this motorcycles engine is not a TZ 500 but rather a TZ 750, which may or may not have been fitted with 250 cylinders, thereby reducing its capacity to 500cc. The TZ 500, in all three versions, featured individual cylinders and heads, whereas the TZ 750 was equipped with two blocks of two cylinders, initially producing 700cc and later the full 750cc. While it was common practice "in the period" to reduce the capacity to 500cc - potentially the case with this motorcycle - such a modification would typically be accompanied by yellow racing number boards, not the white ones seen fitted, which are indicative of a 750-class machine. Accordingly prospective bidders must satisfy themselves as to the provenance, condition, age, completeness, capacity, compatibility and originality of this machines component parts prior to bidding.