Fuel feed system for carburetors on motorcycles

• US 4,385,676 A
• Filed: 04/14/1981
• Issued: 05/31/1983
• Est. Priority Date: 04/22/1980
• Status: Expired due to Fees

• Current Assignee: Honda Giken Kogyo Kabushiki Kaisha (Honda Motor Company)
• Original Assignee: Honda Giken Kogyo Kabushiki Kaisha (Honda Motor Company)
• Inventors: Yoshimura, Shigekazu
• Primary Examiner(s): Myhre, Charles J.
• Assistant Examiner(s): Cross, E. Rollins
• Application Number:
  US06/254,163
• Time in Patent Office: 777 Days
• Field of Search: 123/575, 123/576, 123/577, 123/578, 123/179 G, 123/1 A, 280/5 R, 280/5 A, 280/202, 180/219
• US Class Current: 180/219
• CPC Class Codes: F02B 61/02 for driving cycles
• CPC Class Codes: F02M 1/16 Other means for enriching fuel-air mixture during starting; Priming cups; using different fuels for starting and normal operation
• CPC Class Codes: F02M 13/06 the carburettors using different fuels

Abstract

A system for feeding a fuel to a carburetor on a motorcycle, comprising a frame on which an engine having a carburetor is mounted, a main fuel tank disposed at the front side of an upper portion of the frame for storing fuel such as alcohol therein, and an auxiliary fuel tank disposed at the rear side of the upper portion of the frame for storing fuel such as gasoline therein. The main and auxiliary fuel tanks are in communication with the carburetor through main and auxiliary fuel passages, respectively. A switch cock is provided in the main fuel passage for opening and closing thereof, and a measuring pump is interposed in the auxiliary fuel passage for supplying an auxiliary fuel at a predetermined flow rate from the auxiliary fuel tank to the carburetor. The switch cock and measuring pump are disposed at opposite sides of a lower surface of the main fuel tank. Accordingly, a driver on the motorcycle can easily reach and operate the switch cock and measuring pump in his sitting posture on the motorcycle.

Claims

1. A fuel feed system for carburetors on motorcycles, comprising a frame on which an engine having a carburetor is mounted;

a main fuel tank provided at a front side of an upper portion of said frame for storing alcoholic fuel to be used as a main fuel;

an auxiliary fuel tank provided at a rear side of the upper portion of said frame for storing gasoline to be used as a starting fuel;

a main fuel passage for connection between said main fuel tank and said carburetor, an auxiliary fuel passage for connection between said auxiliary fuel tank and said carburetor;

a switch cock disposed in said main fuel passage and adapted to be manually operated to control supply of alcoholic fuel to said carburetor; and

a measuring pump disposed in said auxiliary fuel passage and adapted to be manually operated to meter and supply a proper amount of gasoline from said auxiliary fuel tank to said carburetor at the time of engine starting, said switch cock and said measuring pump being disposed on opposite sides of a lower surface of said main fuel tank, said pump comprising a pump body, a diaphragm of an elastic material dividing the interior of said pump body into a pump chamber communicating with said auxiliary fuel passage, and an atmospheric pressure chamber communicating with the atmosphere, and a return spring resiliently biasing said diaphragm toward said pump chamber.

2. A fuel feed system for carburetors on motorcycles according to claim 1, wherein said measuring pump comprises a connecting boss formed integrally with a central movable portion of said diaphragm and having a blind bore, an actuator rod having an inner end portion fitted into said connecting boss for elastic engagement and the other end portion extended to the outside of said pump body, and a retainer fitted around the outer circumferential surface of said connecting boss to prevent said connecting boss from being deformed, said retainer being kept pressed against said diaphragm by said return spring.

3. A fuel feed system for carburetors on motorcycles according to claim 2, wherein said connecting rod is provided at its inner end portion with an annular recess, and said connecting boss has an annular projection for engagement with said annular recess.