Meguro 250cc : F The 250cc : F type of new model series obtained a new user layer different from 250cc and the Junior series which was the main force of Meguro, and was developed newly utterly. New style engine was developed based on the track record of engine research with the cam chain system by OHC which obtained good results in the 2nd all Japan motorcycle endurance race (Asama volcano race) held in 1957. F type will start sale from production and July with 125 cc-E3 which is the small new style motorbikes developed from 'June, 58 by the same concept to this combining the body united with the trend of the world. In this development, Meguro did not follow a car conventionally, and the whole composition (style design) was requested and advanced to the external specialist. Having received the request is Mr. Reikichi Yura who was prominent as an industrial designer those days. (A son is Mr. Takuya Yura prominent as a racing car designer) The image light to reference and bright is expressed in the design by the Europe motorcycle maker of those days by Mr. Yura at this new model series. Especially Mr. Yura has deep discernment in an automobile design, and also before and after this development, he inspects Europe and is dealing with many work based on that experience. Although the motorcycle maker of the automaker-technique of starting development was also being uniquely lost from the design work, there were few examples performed by requesting outside rather than developing in the company, YAMAHA utilized the industrial designer group : GK group (the present GK industrial design) from the time of foundation, and design development was performed. Although it is in having adopted the monochrome block by OHC form for the first time as a commercial car of Meguro as the point, the feature of the FH type and the single cylinder OHC 4 cycle engine of F is not that of special structure like the engine for races used as the foundation, and it is rather summarized to the orthodox SOHC organization to the extent that it is too simple. A boa x stroke is 68x68.5 it is the engine of the type made to generate torque with rotation speed in a square-like setup. Although it was the engine of high rotation specification in Meguro, as for roadability ability, the gear ratio is adjusted by the primary gear by the correspondence to the practical use which was the policy of Meguro of those days so that torque may be obtained also for a low speed. By the situation a little sensitive to an accelerator work probably for the reason, it is commented as "a little nervous engine" by the impression by the technical magazine of those days. A cylinder head is an aluminum alloy. It is said that the cylinder devised the special process in order to pour in the aluminum alloy which was the so-called Alfin, included the cylinder sleeve made from a cast steel Sendaito-metal by the special casting process in shell molding, and was solved. The adhesion nature of the heat dissipation part of a sleeve and an aluminum alloy inserts in, it is markedly alike compared with a process, and it is supposed by this process that it is good and heat dissipation nature is good. The main designers are the Shigeji Suzuki which dealt with the engine for races used as the foundation. The body is a novel form which is not in the commercial car of the conventional Meguro summarized based on the basic design by Mr. Reikichi Yura as the point. That it is conspicuous first is a fuel tank which looks large. Although seemed to be strange, when it actually gets on, a settlement is a form with an easy kneepad in a good size to a knee exactly. Since capacity is scooped out in order that the bottom of a tank may improve maintenance nature of the engine upper part, it is as standard as 13L. It is thought with the point referred to as poking by surprise that it has succeeded in design. Although this form like the German vehicle was later commented to be an "iron helmet" etc., it was adopted adding correction to S5(250cc), S7(250cc), CA(125cc), DA(170cc), etc. which appears henceforth, and was able to obtain evaluation. On the other hand, the form which meant the straight line is made into the peculiar appearance which otherwise does not look at a kind by contrast with a dome type fuel tank until it results in a frame, a side cover, and a sheet. Two-tone specification referred to as that the design of the coating also makes others black by making a head and a tank into bright gray from the monotone which used the conventional black etc. as the base. It was enough to acquire the subject that Meguro took out such a motorbike, although other makers were sufficient as such a color scheme, it was adopted and was not new. Later, a color scheme is said that there was rebounding from a user, when the black from the former and plating are changed into the specification used as the base. As it thought that it was at a thing with the conventional more sufficient atmosphere as Meguro, there is a glimpse of confusion of a product concept around there but. Frame composition is dogged specification as usual by the correspondence to a practical use too. It is said that mitigation was not able to do body weight more heavily than appearance probably for the reason. Moreover, according to the trend of the world, the flasher (winker) which still were not maintenance parts is designed and equipped standardly. In addition, it is the specification which suited to the trend of the world of the exchange power generation and selenium rectification by alternator. A muffler chooses the best form from the results of the model experiment by the laboratory of the past Ministry of Transport, and are adoption and a characteristic form. Although especially a sports bike is meant and development is not carried out, the buffer of a rear part is made into the swing arm type from the trend of the world. A gearbox style is a 4 steps of advance rotary type from the former. From F type, the new system (the sending mechanism by the gear and the rachet is changed into a plate type) by which improvement development was newly carried out is merely adopted. Although the impression report of a magazine of those days has that indication that the treading-in stroke of a pedal is too long in whether it is a sake, this specification is also applied to each car in which it appears henceforth. In order to merely unite with the trend of the world, it was changed into the operation method of a left change right brake, and it became the factor by which the user from the former is bewildered. F type was not able to improve the expected track record as a result. And it becomes the cause which leads to next performance uneasiness by dropping the sales performance of 250cc car which can also be called lifeline of Meguro. The reputation to F type of those days is not so bad as it. Although the design which is not in the conventional Meguro attached by surprise, there was no resistance of a Meguro user. The direction of having returned to the conventional monotone by Ushiro's design change rather has incurred an antipathy. The opinion that highly efficient engine is sufficient has not made an issue of the fact that and it is OHC engine, in respect of the performance. Then, where was the reason which cannot be sold? In order for me to consider, I think that change of the operation method to the left change right brake it is supposed that was united with the trend of the world would be suited. Has this change made the user from the former hold puzzlement? It seems that it has been regarded as a motorbike of other completely heterogeneous makers for the Meguro user from the former although Meguro put the operation method of the specification which was becoming in use with the method of profit about a new user layer, i.e., the high rotation engine by OHC monochrome block form, the designed body, and a left change right brake etc., and it was crowded, and these were generally permeating. Since it was general to the bad thing, when seeing to it, since the image of Meguro called practical use vehicle maker from the former was too strong, the customer who wants to newly gain Meguro did not come near. How much new users who dared get interested in this motorbike and thought "I want to buy it" by Meguro having taken out such a new model were there? Although not having been attached, so that he will buy it from a Meguro user, it will cut down as a result and the new user also considered thinks that it was the dull factor of F ..... Possibly, if it is the operation method of a right change left brake as usual, a Meguro user will think that possibly resistance did not appear in buying it also with F type. F type with which a track record was not improved became the place for which it compensates by S5 immediately prepared by the conventional specification and the improved sales of S7, and became a production stop in 'May, 60. The number of the gross product was about 1500 sets. In addition, although the 350cc class FY which set the boa x stroke to 74x75.5 as an F type derivation model in '59 is announced, FA Argus which made a specification change again is sold to the sports model the beginning. Although it is unknown whether there is nothing with a track record and it is how much existing as for most F series, it is one set which a good thing or a bad thing also wants to leave only to the epoch-motorbike of Meguro by somewhere. *** Principal statistics *** * Total length : 2,055 mm * Full-width : 720 mm * Total height : 1,000 mm * Distance between axis : 1,350 mm * Weight : 160 kgf * Engine type : FH type: Single cylinder OHC 4 cycle * Entire aerodynamic volume displacement : 249 cc * Installed capacity : 14.8 HP / 6,000 rpm * Full speed : 115 km/h * Fuel economy : 45 km/L * Transmission : Advance 4 step rotary * Tire : (Front) 3.00x18-4 / (Rear) 3.25x18-4 * Starting system : Kick