Abstract: There are provided a mirror device and a straddle-type vehicle including: a stay attached to a vehicle body; a housing supported on the stay; a mirror mechanism including a mirror and a holding portion that holds the mirror, at least a part of the holding portion being accommodated in the housing, and the mirror mechanism being attached to the housing; and an attachment portion in which a receiving portion subjected to an attachment and detachment operation is exposed to an outside of the housing and the mirror mechanism, the attachment portion detachably attaching the mirror mechanism to the housing.

Abstract: A fluid mixing apparatus includes a pipe in which fluid flows, an injection section for injecting an injection gas into the fluid and a supplying section for supplying the injection gas to the injection section. The apparatus further includes at least one element downstream of the injection section and/or an injection tube in the injection section to uniformly distribute and/or inject the injection gas into the fluid.

Abstract: An exhaust gas flow rate measuring equipment for internal combustion engines supplies helium gas only to a trace gas analyzer. The condition in which the inside of the trace gas analyzer in the high-vacuum stage causes pressure fluctuation due to the viscosity of the exhaust gas and the introduction rate of helium gas fluctuates in proportion to the fluctuation rate can be prevented. Also the, problem of the sensitivity varying in accordance with the gas component ratio in the exhaust gas can be solved.

Abstract: V-type engine has intake and exhaust valves for each cylinder, the intake valve being inclined at an angle relative to a center line of each cylinder bore larger than an angle relative to the center line at which the exhaust valve is inclined, and having a length between an intake valve face and an intake cam longer than a length between an exhaust valve face and an exhaust cam of the exhaust valve.