CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to and the benefit of Japanese Patent Application No. 2019-123351, filed on Jul. 2, 2019, the entire disclosure of which is incorporated herein by reference.

BACKGROUND OF THE INVENTION

Field of the Invention

The present disclosure relates to a straddle vehicle such as a motorcycle.

Description of the Related Art

In a power unit of a vehicle such as a motorcycle, an oil is drawn from an oil pan into an oil pump, and the oil discharged from the oil pump is supplied to an oil control valve unit (clutch controller) through a primary filter and a secondary filter (see Japanese Patent No. 5020765, for example). The primary filter is placed in the oil pan mounted beneath a crankcase, and the secondary filter is disposed inside the crankcase.

In the above configuration, when maintenance operations are performed on both of the primary and secondary filters, the power unit needs to be disassembled to a sufficient extent. Thus, the efficiency of the maintenance operations is low.

SUMMARY OF THE INVENTION

A straddle vehicle according to one aspect of the present disclosure includes: a prime mover; a hydraulically actuated main clutch disposed in a power transmission route between the prime mover and a drive wheel; an oil control valve unit that controls flow of a hydraulic oil supplied to the main clutch; a power unit case accommodating at least the main clutch; an oil pan mounted beneath the power unit case and retaining an oil; a clutch-dedicated pump that sucks the oil from the oil pan and that discharges the sucked oil as the hydraulic oil toward the oil control valve unit; a primary filter disposed in an oil passage between the oil pan and the clutch-dedicated pump; and a secondary filter disposed in an oil passage between the clutch-dedicated pump and the oil control valve unit, wherein the primary filter and the secondary filter are mounted on a bottom surface of the power unit case and covered from below by the oil pan.

With the above configuration, both the primary filter and the secondary filter are made easily accessible by removing the oil pan. This improves the ease of maintenance of the two filters.

In an exemplary configuration, the power unit case and the oil pan may be shaped to form together an accommodation chamber in which the secondary filter is accommodated.

With this configuration, the accommodation chamber for the secondary filter can easily be formed by mounting the oil pan on the power unit case.

In an exemplary configuration, the straddle vehicle may further include: a prime mover-dedicated pump that sucks the oil from the oil pan and discharges the sucked oil toward the prime mover to lubricate the prime mover; and another secondary filter disposed in an oil passage between the prime mover-dedicated pump and the prime mover, and suction inlets of the clutch-dedicated pump and the prime mover-dedicated pump may communicate with the primary filter.

With this configuration, since the primary filter is used for both the clutch-dedicated pump and the engine-dedicated pump, an increase in the number of required components and an increase in size of the space required for arrangement of the components can be prevented. Additionally, since different pumps are used as the clutch-dedicated pump and the engine-dedicated pump, respectively, the hydraulic oil can be supplied quickly to the main clutch even at the start-up of the prime mover. If a single pump is used for both the clutch and the prime mover, more of the oil will be delivered toward the prime mover (the low pressure side) than toward the clutch at the start-up of the prime mover, and a long time will be required for the main clutch to become operable. With the above configuration, the time required for the main clutch to become operable can be shortened even at the start-up of the prime mover.

In an exemplary configuration, the clutch-dedicated pump and the prime mover-dedicated pump may be coaxially connected to each other.

With this configuration, the straddle vehicle can be made compact.

In an exemplary configuration, the straddle vehicle may further include: a relief valve disposed between the clutch-dedicated pump and the oil control valve unit; and a bypass passage through which the oil discharged from the relief valve is introduced into an oil passage between the primary filter and the clutch-dedicated pump without passing through the primary filter.

With this configuration, the amount of the oil sucked from the oil pan through the primary filter can be reduced, and thus the energy loss due to the passing of the oil through the primary filter can be reduced.

In an exemplary configuration, the power unit case may include an opening communicating with the oil passage between the primary filter and the clutch-dedicated pump, and the power unit case and the oil pan may be shaped to form together a communication chamber as the bypass passage, the communication chamber communicating with the relief valve and the opening.

With this configuration, the bypass passage can easily be formed by mounting the oil pan on the power unit case.

