High-pressure fuel pipe

A high-pressure fuel pipe applied to a cylinder injection type engine that directly injects fuel into a combustion chamber with an injector, wherein

• the high-pressure fuel pipe is a pipe disposed between the injector and a high-pressure fuel pump,
• the high-pressure fuel pump is provided on a downstream side of a low-pressure fuel pump,
• the engine is a single cylinder or a two-cylinder,
• the high-pressure fuel pump is a plunger type that performs pressurization once or twice per rotation in synchronization with a camshaft of the engine, and
• a value of a volume of the high-pressure fuel pipe is k×Q/ΔP/1000×n or less, where k is a volume modulus of fuel, Q is a maximum discharge amount of the fuel in one reciprocation of the high-pressure fuel pump, ΔP is a difference between a target fuel pressure boosted by the high-pressure fuel pump and a feed fuel pressure boosted by the low-pressure fuel pump, and n is a number of times of boosting in one rotation of the high-pressure fuel pump.