Meguro 250cc : J Junior Meguro 250cc : J is the first model of the old Junior series, and it is the first 250cc motorbike in Japan. About 800 sets were manufactured from the appearance in December, 1950 before 'December, 51. It is supposed from positioning called child of Z (500 cc) which is the prime motorbike of Meguro that "J" was named from the initial of a "Junior." And as a motorcycle of Meguro, nickname was attached for the first time, and, similarly it was called the "Junior." J Junior's J type engine was newly developed as first engine for 250cc motorbikes in Japan as stated previously. It seems that calling it a 500cc:Z type half simply set to 250cc. A developer is Mr. Tetsuji Makita who had acquired fame by automobile development from the 2W-War front. Makita designed "Otomo" which became the mass-production car of the domestic beginning of Japan 1923. Then, he is the person who dealt with development of a three small car "Newera" and development of "Kurogane-Yonku" which is a Japanese domestic four-wheel drive car (4WD) and who was called genius of automobile development. At the time of J type engine of a design, it was in office in Nippon-Nainenki-Seizo. As for Makita, development of 250cc engine also demonstrates the talent, and it is said that the design was completed in a night. Mr. Takeo Suzuki who was the "Meguro-Seisakusyo" director is recollecting the thing of those days later. "-- Mr. Makita came from the same Shizuoka (Shimada) as the managing director, Mr. Kouji Suzuki, and since he was the person who acquired reputation by the engine design of the three-flower car "Kurogane" of Nippon-Nainenki etc., he needed your help. If a prototype is built, it is not in good order somehow. Then, the place tried on saying that a stroke will be shortened became good." The engine style of subsequent Meguro of J type engine is heterogeneous, and the push rod is dedicated to the inside with the 4 cycle 246cc single cylinder OHV, and it is not visible from appearance. Moreover, arrangement of timing mechanisms, such as magneto, has the features, like it is ahead of engine. The boa x stroke of the time of a trial production: Although 65x75 was corrected to 70x64 as it was described previously, it was returned to the original boa x stroke : 65x75 in J2(250cc) which expansive improvement is carried out to the next year, and appears. This became the basic specification of subsequent Meguro engine. Because of composition whose frame made 500cc : Z light as they were, there is no rear suspension and it is rigid frame. Not the garter type till then but the telescopic type is first adopted as the front fork by Meguro. *** Principal statistics *** * Total length : 2,140 mm * Full-width : 780 mm * Total height : 1,000 mm * Distance between axis : 1,390 mm * Weight : 174 kgf * Engine type : J type : Single cylinder OHV 4 cycle * Entire aerodynamic volume displacement : 246 cc * Installed capacity : 7.0 HP / 4,000 rpm * Full speed : 70 km/h * Fuel economy : - km/L * Transmission : Advance 3 step * Tire : (Front) 3.00~20-4 / (Rear) 3.00~20-4 * Starting system : Kick