JP6044241B2 - Saddle riding vehicle - Google Patents

Description

  The present invention relates to a saddle riding type vehicle. In particular, the present invention relates to an arrangement of a transmission and a starter for an engine mounted on a saddle riding type vehicle.

  In general, a motorcycle or the like as a straddle-type vehicle is transmitted to a rear wheel via a drive sprocket, a drive chain, and a driven sprocket after the rotation of a crankshaft is changed by a transmission. The transmission includes a counter shaft, a drive shaft, a plurality of transmission gears arranged between the counter shaft and the drive shaft, a gear shift mechanism, and the like. The gear shift mechanism has a shift cam that rotates in response to a shift operation by an occupant, and a shift fork that changes the meshing between a plurality of transmission gears by the rotation of the shift cam. Since the shift cam changes the meshing between the transmission gears via the shift fork, it is preferably arranged at a position close to a counter shaft or a drive shaft where a plurality of transmission gears are arranged.

  Some motorcycles are provided with a starter having a starter motor in order to improve convenience. Since the starting device forcibly rotates the crankshaft by the starter motor to start the engine, it is preferable that the starting device is disposed at a position close to the crankshaft.

  For example, in the engine shown in Patent Document 1, in a side view, a shift cam (shift drum) of a gear shift mechanism (gear change mechanism) is arranged on the rear side of the crankshaft, and a starter motor of the starter is arranged on the front side of the crankshaft. Is disclosed.

JP 2011-74980 A

  However, if the shift cam and the starter motor are arranged in front of and behind the crankshaft as in the engine of Patent Document 1 described above, a space for arranging the shift cam and the starter motor is required, and the engine becomes larger and the weight increases accordingly. There is a problem that it ends up.

  Further, if the starter is disposed at a position away from the center of the engine, the mass cannot be concentrated, and there is a possibility that the stability of the maneuvering may be adversely affected.

  The present invention has been made in view of the above-described problems. By disposing the shift cam of the gear shift mechanism and the starter motor of the starter at predetermined positions, the engine can be downsized and the operation stability can be improved. A straddle-type vehicle capable of achieving the above is provided.

The straddle-type vehicle according to the present invention includes a crankshaft, a countershaft in which rotation of the crankshaft is transmitted via a clutch, and rotation of the countershaft is transmitted through a plurality of transmission gears. A drive shaft coupled with a drive sprocket around which a drive chain for transmitting a driving force is wound, a shift cam for changing a combination of the plurality of transmission gears via a shift fork, the crank shaft, the counter shaft, A crankcase that rotatably supports the drive shaft and the shift cam, a cylinder block that is disposed forwardly inclined to the crankcase, and a crankshaft that is disposed on the rear side of the cylinder block via a start gear. A starter motor for forcibly rotating the A straddle-type vehicle provided with a down in a side view, the axis of the shift cam will be the axis of the crankshaft, the axis of the drive shaft, the apex of the axis of the output shaft of the starter motor three It is arranged inside the square region.

  According to the present invention, by disposing the shift cam and the starter motor at predetermined positions, it is possible to reduce the size of the engine and to improve the stability of steering.

1 is a left side view showing an overall configuration of a motorcycle. It is a left view which shows the structure of an engine periphery. It is a left side sectional view of an engine. It is right side sectional drawing of an engine. It is the perspective view which looked at the II line cross section shown in FIG. 2 from the arrow direction. It is a left side sectional view of an engine. It is the perspective view which looked at a part of transmission from the back side. It is the perspective view which looked at a part of transmission from the right side. It is the figure seen from the arrow A direction shown in FIG. It is right side sectional drawing of an engine.

Hereinafter, preferred embodiments of a saddle riding type vehicle according to the present invention will be described with reference to the drawings. In the present embodiment, a motorcycle will be described as a saddle riding type vehicle.
FIG. 1 is a left side view showing the overall configuration of the motorcycle 100. In the drawings used in the following description, the front side of the vehicle is indicated by an arrow Fr and the rear side of the vehicle is indicated by an arrow Rr as necessary. Further, the right side of the vehicle is indicated by an arrow R, and the left side of the vehicle is indicated by an arrow L.

  As shown in FIG. 1, a motorcycle 100 is provided with two left and right front forks 103 supported by a steering head pipe 102 so as to be turnable left and right at the front of a main frame 101 made of steel or aluminum alloy. It has been. A handle bar 104 is fixed to the upper end of the front fork 103. Grips 105 are attached to both ends of the handle bar 104. A clutch lever, a starter switch, and the like (not shown) that are operated by the occupant are disposed at positions close to the grip 105. A front wheel 106 is rotatably supported at the lower portion of the front fork 103. The front wheel 106 is covered with a front fender 107 at the top. A brake disc 108 that rotates integrally with the front wheel 106 is attached to the front wheel 106.

  The main frame 101 is connected to the rear part of the steering head pipe 102, branches left and right toward the rear side, and extends obliquely downward and rearward while widening. In the vicinity of the rear portion of the main frame 101, a seat rail 109 that is inclined moderately rearward and upward is extended to support the seat 110 including the rider seat 110a and the tandem seat 110b. A body frame is constituted by the main frame 101 and the seat rail 109. A swing arm 111 is coupled to the rear portion of the main frame 101 so as to be swingable about a pivot shaft 112. A rear shock absorber 113 is mounted between the main frame 101 and the swing arm 111. Below the pivot shaft 112, a shift change pedal 114 is arranged for a passenger to perform a shift operation. The shift operation via the shift change pedal 114 is input via a shift rod 115 to a gear shift mechanism which will be described later.

A rear wheel 116 is rotatably supported at the rear end of the swing arm 111. The rear wheel 116 is rotationally driven via a driven sprocket 118 around which a drive chain 117 that transmits the driving force of an engine, which will be described later, is wound. An inner fender 119 that covers the vicinity of the front upper portion is disposed in the immediate vicinity of the rear wheel 116, and a rear fender 120 is disposed above the inner fender 119.
An engine 200 is mounted on the main frame 101. The engine 200 is integrally coupled to the main frame 101 via a plurality of suspension portions as will be described later. As the engine 200 of this embodiment, for example, a 4-cycle multi-cylinder, typically a 4-cylinder engine is used.

  A fuel tank 121 having a dome shape is mounted above the engine 200. The fuel tank 121 is supported on the main frame 101 so as to cover the entire upper part of the main frame 101 from above. An air cleaner 122 for supplying clean air to the engine 200 is arranged between the engine 200 and the fuel tank 121. The air cleaned by the air cleaner 122 is mixed with the fuel in the fuel tank 121 and supplied into the engine 200. Exhaust gas generated by burning the air-fuel mixture in the engine 200 is exhausted from the exhaust device 124 via the exhaust pipe 123.

  In the vehicle exterior, the front and side portions of the vehicle are covered with a fairing 125 and a side cowl 126. Further, the periphery of the seat 110 is covered with a seat cowl 127. The exterior form of a vehicle having a streamlined shape is formed by exterior members such as a fairing 125, a side cowl 126, and a seat cowl 127.

Next, the engine 200 according to the present embodiment will be described with reference to FIGS. FIG. 2 is a left side view showing the configuration around the engine 200. FIG. 3 is a left side sectional view of the engine 200. FIG. 4 is a right side sectional view of the engine 200. FIG. 5 is a perspective view of the cross section taken along the line I-I shown in FIG.
As shown in FIG. 2, the engine 200 includes a crankcase 201, a cylinder block 202 that extends forward from the crankcase 201, a cylinder head 203 that is disposed above the cylinder block 202, and a cylinder head A cylinder head cover 204 that closes 203 from above is integrally coupled.

The engine 200 is suspended on the main frame 101 via a plurality of suspension portions.
Specifically, as shown in FIG. 5, shaft holes 210a and 210b as suspension portions are formed on the upper and lower sides of the crankcase 201, respectively. On the other hand, on the left and right main frames 101, shaft holes 128a and 128b communicating with the shaft holes 210a and 210b are formed above and below the pivot shaft 112, respectively. The rear side of the crankcase 201 is located between the left and right main frames 101, and bolts (not shown) are inserted into the shaft holes 128a, 210a, the shaft holes 128b, and the shaft holes 210b and fastened to the main frame 101. Combined.
Further, as shown in FIG. 2, the engine 200 is coupled to the main frame 101 by fastening a cylinder head 203 and a suspension frame 129 that branches from the steering head pipe 102 to the lower side of the main frame 101 with bolts (not shown). Is done.

As shown in FIG. 2, the crankcase 201 includes a crank chamber 205, a magnet chamber 206 located on one side (left side) of the crank chamber 205, a mission chamber 207 located on the rear side of the crank chamber 205, and the other of the mission chamber 207. A clutch chamber 208 positioned on the side (right side), a breather chamber 209 positioned on the rear side of the mission chamber 207, and the like are formed.
The crankcase 201 of the present embodiment is formed by being divided into upper and lower parts by an upper upper case 201a and a lower lower case 201b, and a crankshaft 211 disposed on the divided surface along the vehicle body width direction (left-right direction). Is pivotally supported. As shown in FIG. 4, a primary drive gear 212 that rotates integrally with the crankshaft 211 is attached to the other side (right side) of the crankshaft 211.

  As shown in FIG. 3, a cylinder block 202 is formed integrally with the upper case 201a. The cylinder axis Lcy of the cylinder block 202 is inclined forward approximately 30 degrees with respect to the vertical line, and is orthogonal to the dividing surface Fd. The cylinder block 202 has a piston 213 disposed therein so as to be capable of reciprocating along the cylinder axis Lcy. The piston 213 and the crankshaft 211 are connected via a connecting rod 214. The reciprocating motion of the piston 213 is converted into the rotation of the crankshaft 211 via the connecting rod 214.

A cylinder head 203 is coupled to the top of the cylinder block 202 to form a combustion chamber 215 therein. A spark plug 216 is disposed on the cylinder head 203 so that its tip is disposed in the combustion chamber 215.
An intake port 217 and an exhaust port 218 communicating with the combustion chamber 215 are formed in the cylinder head 203. An intake valve 219 is disposed in the intake port 217, and an exhaust valve 220 is disposed in the exhaust port 218. A cylinder head cover 204 is coupled to the top of the cylinder head 203 and covers a valve gear including the intake valve 219 and the exhaust valve 220.

  An oil pan 221 is provided at the lower end of the crankcase 201. Part of the oil pan 221 protrudes downward from the right side of the exhaust pipe 123 so as not to interfere with the exhaust pipe 123. FIG. 6 is a left sectional view of the engine 200, and is a view cut on the right side in the vehicle body width direction from FIG. An oil pump 222 for circulating engine oil in the oil pan 221 to each component of the engine 200 is disposed above the oil pan 221 and below a drive shaft described later. The oil pump 222 is driven along with the rotation of the crankshaft 211, passes engine oil sucked from the oil strainer 223 through an oil cooler 224 and an oil filter (not shown) installed on the front side of the lower case 201b, and then the engine 200. Supply to each part.

  Returning to FIG. 3, a balancer shaft 225 is rotatably supported on a split surface Fd between the upper case 201a and the lower case 201b on the front side of the crankcase 201. A balancer weight 226 is integrally coupled to the balancer shaft 225 and rotates in conjunction with the rotation of the crankshaft 211 to reduce vibration of the engine 200.

Next, a transmission 230 that transmits the rotation of the crankshaft 211 to the drive chain 117 in accordance with the operation of the shift change pedal 114 by the occupant will be described with reference to FIGS. 3, 4, and 7 to 9. To do. FIG. 7 is a perspective view of a part of the transmission 230 as seen from the rear side. FIG. 8 is a perspective view of a part of the transmission 230 as viewed from the right side. FIG. 9 is a view of the transmission 230 as seen from the direction of arrow A shown in FIG.
The transmission device 230 is disposed in the mission chamber 207, and includes a counter shaft 231, a clutch 233, a drive shaft 234, a transmission gear 235 provided on the counter shaft 231 and the drive shaft 234, and a gear shift mechanism 240 that operates a plurality of transmission gears 235. have.

  The counter shaft 231 and the drive shaft 234 are disposed in parallel with the crankshaft 211 in the mission chamber 207. As shown in FIGS. 3 and 4, the counter shaft 231 is rotatably supported by a split surface Fd between the upper case 201 a and the lower case 201 b on the rear side of the crankshaft 211. Further, the drive shaft 234 is rotatably supported by the lower case 201b on the rear side of the crankshaft 211 and below the counter shaft 231.

  As shown in FIG. 7, on the right side of the counter shaft 231, a primary driven gear 232 that rotates integrally with the counter shaft 231 and always meshes with the above-described primary drive gear 212 is mounted. The primary driven gear 232 is disposed in the clutch chamber 208 or close to the clutch chamber 208, and a clutch 233 is provided on the right side of the primary driven gear 232. The clutch 233 is covered with a clutch cover (not shown) from the right side of the crankcase 201. The clutch 233 intermittently transmits rotation between the primary driven gear 232 and the counter shaft 231 in accordance with an operation by the occupant via the clutch lever. Specifically, rotation of the crankshaft 211 is transmitted to the countershaft 231 when the clutch 233 is engaged. On the other hand, when the clutch 233 is disengaged, the primary driven gear 232 idles and the rotation of the crankshaft 211 is not transmitted to the countershaft 231.

Each of the counter shaft 231 and the drive shaft 234 is provided with a plurality of transmission gears 235.
Here, some of the plurality of transmission gears 235 provided on the countershaft 231 rotate integrally with the countershaft 231 (such transmission gears 235 are referred to as “integrated rotation gears”). The remaining transmission gear 235 is rotatable relative to the counter shaft 231 (such a transmission gear 235 is referred to as a “free rotation gear”). A part of the integral rotation gear can reciprocate in the axial direction of the counter shaft 231 (such a transmission gear 235 is referred to as a “slide rotation gear”). A dog clutch is provided on the slide rotation gear and the free rotation gear adjacent to the slide rotation gear. When the slide rotation gear and the free rotation gear come close to each other, the dog clutch is engaged, and the free rotation gear rotates together with the counter shaft 231. On the other hand, when the slide rotation gear and the free rotation gear are separated from each other, the dog clutch is disengaged, and the free rotation gear is rotatable relative to the counter shaft 231.

The plurality of transmission gears 235 provided on the drive shaft 234 are configured in the same manner as the plurality of transmission gears 235 provided on the counter shaft 231.
Each of the integral rotation gears provided on the counter shaft 231 and each of the free rotation gears provided on the drive shaft 234 are always meshed with each other. Similarly, each of the free rotation gears provided on the counter shaft 231 and each of the integral rotation gears provided on the drive shaft 234 are always meshed with each other.
The gear shift mechanism 240 moves the slide rotation gear in the axial direction of the counter shaft 231 or the drive shaft 234 in accordance with a shift operation via the shift change pedal 114 by the occupant. The combination of the transmission gear 235 that transmits the rotation from the counter shaft 231 to the drive shaft 234 is changed by the movement of the slide rotation gear.

  A drive sprocket 236 that rotates integrally with the drive shaft 234 and is wound with the drive chain 117 is attached to the left end portion of the drive shaft 234 (see FIG. 2). Therefore, the rotation of the crankshaft 211 is shifted by the transmission 230 and output to the drive sprocket 236 and transmitted to the rear wheel 116 via the drive chain 117 and the driven sprocket 118.

Next, the gear shift mechanism 240 that changes the combination of the transmission gears 235 according to the shift operation of the shift change pedal 114 by the occupant will be described with reference to FIGS. 3, 4, and 7 to 9.
The gear shift mechanism 240 is disposed in the mission chamber 207 and includes a shift shaft 241, a shift arm 242, a shift cam 244, a shift cam stopper 250, and a shift fork 251.

  The shift shaft 241 is disposed in parallel with the crankshaft 211 and is pivotally supported by the upper case 201a above the shift cam 244 and on the upper case 201a. The shift shaft 241 rotates in conjunction with the shift operation of the shift change pedal 114 by the occupant. For example, a shift operation for upshifting rotates in one direction, and a shift operation for downshifting rotates in the other direction. As shown in FIG. 8, a shift arm 242 that swings in the arrow direction as the shift shaft 241 rotates is pivotally attached to the right end portion of the shift shaft 241. The shift arm 242 is formed in a plate shape having a spatula shape extending downward, and is arranged at a position so as to cover the shift cam 244 from the right side. The shift arm 242 is formed with a substantially rectangular opening 243 that engages with a part of a plurality of shift pins 248 of a shift cam 244 described later. In FIG. 4, the neutral state of the shift arm 242 is indicated by a solid line, and the swing ranges before and after the neutral state are indicated by two-dot chain lines. The shift arm 242 swings in either the front or rear direction according to the rotation of the shift shaft 241 and is biased to return to the neutral state after swinging.

  The shift cam 244 is disposed in parallel with the crankshaft 211 and is pivotally supported by the upper case 201a. The shift cam 244 has a cam body 245 and a stopper plate 247. The cam main body 245 is a cylindrical cam. A predetermined number and shape of cam grooves 246 are formed on the outer peripheral surface of the cam body 245. In the present embodiment, three cam grooves 246 are formed. The stopper plate 247 is fixed to the right end of the cam body 245 and is formed in a plate shape having a predetermined thickness in the axial direction. A plurality of shift pins 248 are provided on the right end surface of the stopper plate 247. The plurality of shift pins 248 are pin-like members that protrude to the right in the axial direction. The plurality of shift pins 248 are provided so as to be arranged at equal intervals in the circumferential direction at positions spaced apart from the rotation center of the shift cam 244 by a predetermined distance in the radial direction. A part of the plurality of shift pins 248 engages in the opening 243 of the shift arm 242. Therefore, when the shift arm 242 is swung, the stopper plate 247 is rotated through a part of the engaged shift pin 248, and the cam main body 245 is similarly rotated. When the shift arm 242 returns to the neutral state after swinging, it engages with a shift pin 248 different from the shift pin 248 engaged in the neutral state before swinging.

  The stopper plate 247 has concave positioning portions 249 formed on the outer peripheral surface at equal intervals in the circumferential direction (see FIG. 4). The shift cam stopper 250 is disposed at a position close to the stopper plate 247 of the shift cam 244. The shift cam stopper 250 is urged in a direction to engage with the positioning portion 249 of the stopper plate 247 and engages with the positioning portion 249 to position the rotational position of the shift cam 244. Accordingly, it is possible to prevent the shift cam 244 from being inadvertently rotated due to vibration of the engine 200 or the like.

  The shift fork 251 is supported so as to reciprocate along the shift fork shaft 252 (see FIGS. 3 and 9). In the present embodiment, three shift forks 251 are provided. The shift fork shaft 252 is disposed in parallel with the counter shaft 231 and the drive shaft 234, and is pivotally supported by a split surface Fd between the upper case 201a and the lower case 201b. The shift fork 251 engages with a predetermined cam groove 246 of the shift cam 244, and also has a predetermined slide rotation gear (transmission gear 235) provided on the counter shaft 231 or a predetermined slide rotation gear ( Engage with transmission gear 235). When the shift cam 244 rotates according to the rotation of the stopper plate 247, the shift fork 251 moves in the axial direction of the shift fork shaft 252 according to the shape of the cam groove 246. The shift fork 251 moves a predetermined slide rotation gear (transmission gear 235) in the axial direction of the counter shaft 231 or the drive shaft 234 according to the movement. When the predetermined slide rotation gear (transmission gear 235) moves, the rotation transmission path from the counter shaft 231 to the drive shaft 234, that is, the combination of the transmission gear 235 is changed.

  The motorcycle 100 of the present embodiment is provided with a starting device 260 that starts the engine 200 by forcibly turning the crankshaft 211 in accordance with the starter switch operation by the occupant. Here, the starter 260 will be described with reference to FIGS. 2 to 4 and 7 to 9. The starter 260 has a starter motor 261, a torque limiter 264, and a starter gear. The starter gear of the present embodiment is composed of a plurality, and specifically includes a first idle gear 269 and a second idle gear 270.

  The starter motor 261 is disposed in a valley-like space formed between the rear side of the cylinder block 202 and the crankcase 201. As shown in FIGS. 7 to 9, the output shaft 262 of the starter motor 261 extends toward the right side. A gear 263 is formed at the tip of the output shaft 262 of the starter motor 261 and meshes with the torque limiter 264. The torque limiter 264 is disposed below the starter motor 261 and in the upper case 201a. The torque limiter 264 is configured to transmit only the torque from the starter motor 261 to the crankshaft 211 side and to block the torque from the crankshaft 211 side to the starter motor 261 side. The shaft 265 of the torque limiter 264 extends toward the right side. As shown in FIGS. 8 and 9, a first transmission gear 266 is pivotally attached to the tip of the shaft 265 and meshes with the second transmission gear 267.

The second transmission gear 267 is disposed in the upper case 201 a of the crankcase 201 and obliquely below the front of the first transmission gear 266. The first transmission gear 266 and the second transmission gear 267 are formed to have the same diameter so that the manufacturing cost can be reduced. Therefore, the second transmission gear 267 does not decelerate between the first transmission gear 266 and the subsequent first idle gear 269 and the second idle gear 270 are moved to a desired position, that is, diagonally forward and downward. It has a role to arrange.
The shaft 268 of the second transmission gear 267 extends toward the right side. A first idle gear 269 having a diameter larger than that of the second transmission gear 267 is attached to the tip of the shaft 268. As shown in FIG. 8, the shaft 268 is disposed so as not to interfere with the gear shift mechanism 240, specifically, the shift arm 242 and the shift cam stopper 250. In the present embodiment, as shown in FIG. 9, the second transmission gear 267 and the first idle gear 269 are arranged on the left and right with the shift arm 242 interposed therebetween. Further, as shown in FIG. 4, the first idle gear 269 is arranged so that a part of the shift cam stopper 250 overlaps in a side view. The first idle gear 269 meshes with the second idle gear 270 having a larger diameter than the first idle gear 269.

  The second idle gear 270 is disposed on the shaft 271 in the upper case 201 a of the crankcase 201 and obliquely below the first idle gear 269. As shown in FIG. 4, the second idle gear 270 is disposed below the cylinder block 202 in the cylinder axis Lcy direction in a side view. The second idle gear 270 is arranged so that a part of the shift arm 242, more specifically, a swing range of the shift arm 242 (two-dot chain line shown in FIG. 4) overlaps. The second idle gear 270 meshes with a one-way clutch 272 that is pivotally attached to the right end portion of the crankshaft 211 that is disposed obliquely below the front.

  The starter motor 261 rotates in response to an operation by the occupant via the starter switch. As the starter motor 261 rotates, the crankshaft 211 is forcibly rotated via the first transmission gear 266, the second transmission gear 267, the first idle gear 269, and the second idle gear 270. Then, the engine 200 starts.

Next, in the engine 200 configured as described above, the arrangement of the gear shift mechanism 240 and the starter 260 that can reduce the size of the engine 200 and can stabilize the steering of the motorcycle will be described in detail.
FIG. 10 is a right side sectional view of the engine 200, which is the same as FIG.
First, the starter motor 261 of the starter 260 is disposed on the rear side of the cylinder block 202. Then, as shown in FIG. 10, a rectangular region R1 passing through the axis Lcr of the crankshaft 211, the axis Ld of the drive shaft 234, and the axis Lm of the output shaft 262 of the starter motor 261 is assumed. In the present embodiment, the axis Lca (rotation center) of the shift cam 244 of the gear shift mechanism 240 is disposed inside the quadrangular region R1 in a side view. By disposing the axis Lca of the shift cam 244 in the narrow quadrangular region R1, the front and rear and vertical dimensions of the engine 200 can be reduced, and the engine 200 can be downsized. In addition, since the mass can be concentrated, the occupant can stably operate the motorcycle.

  Further, as shown in FIG. 10, a triangular region R2 having apexes of the axis Lcr of the crankshaft 211, the axis Ld of the drive shaft 234, and the axis Lm of the output shaft 262 of the starter motor 261 is assumed. In the present embodiment, the axis Lca of the shift cam 244 of the gear shift mechanism 240 is disposed inside the triangular region R2 in a side view. By arranging the shift cam 244 in the triangular region R2 that is narrower than the rectangular region R1, the front and rear and vertical dimensions of the engine 200 can be further reduced, and the engine 200 can be downsized and the mass can be concentrated. it can.

Further, in a side view, the second idle gear 270 of the starter gear of the starter 260 is disposed so as to overlap the swing range of the shift arm 242 (see the two-dot chain line shown in FIG. 4). Note that the first idle gear 269 may overlap the swing range of the shift arm 242, or at least one of the starting devices 260 may overlap the neutral shift arm 242 (in FIG. 10, the neutral state). The shift arm 242 is indicated by a two-dot chain line).
Further, in a side view, the first idle gear 269 and the second idle gear 270 of the starter gear of the starter 260 are disposed so as to overlap the shift cam stopper 250. The first idle gear 269 and the second idle gear 270 are not limited to the case where both of the first idle gear 269 and the second idle gear 270 overlap with the shift cam stopper 250, and at least one of the first idle gear 269 and the second idle gear 270 may overlap. Good.
As described above, in the side view, the starter gear is disposed so as to overlap the shift arm 242 and the shift cam stopper 250, so that each component can be disposed at an optimal position. Furthermore, since the space in the crankcase 201 can be used effectively, the engine 200 can be further downsized.

Further, in the side view, the axis Li1 of the shaft 268 of the first idle gear 269 of the starter gear is disposed in front of the axis Ls of the shaft 265 of the torque limiter 264, and the shaft 268 and the shaft 265 are respectively attached to the shaft The second transmission gear 267 and the first transmission gear 266 are connected. Thus, by arranging the starting gear on the front side, a space for arranging the shift cam 244 can be secured.
At this time, since the first transmission gear 266 and the second transmission gear 267 mounted on the shaft 265 and the shaft 268 have the same diameter, the cost for manufacturing the transmission gear can be reduced.

Further, in a side view, the second idle gear 270 is disposed below the cylinder block 202 in the axial direction of the cylinder axis Lcy. Therefore, since the entire starter 260 can be disposed on the front side, the shift cam 244 can be disposed on the front side, and the engine 200 can be downsized.
In addition, when viewed from the side, the axis Lco of the countershaft 231 is disposed outside the above-described triangular region R2. If the axis Lco of the countershaft 231 is disposed inside the above-described triangular region R2, the triangular region R2 becomes large and the engine 200 becomes large. Therefore, as in the present embodiment, the shift cam 244 that is generally smaller than the counter shaft 231 is disposed inside the triangular region R2, so that the triangular region R2 is reduced, and the engine 200 is downsized and the mass is concentrated. be able to.

Further, in a side view, the axis Li1 of the shaft 268 of the first idle gear 269 is disposed so as to overlap the outer shape of the torque limiter 264 (see the broken line shown in FIG. 10). Therefore, the distance between the axis Ls of the shaft 265 of the torque limiter 264 and the axis Li1 of the shaft 268 of the first idle gear 269 can be shortened, and the space for arranging components can be saved.
Further, the starting device 260 of the present embodiment is disposed in front of the transmission device 230 in the crankcase 201. Therefore, since the starter 260 is supported by the crankcase 201 whose rigidity is increased in order to support the transmission 230, the support rigidity can be easily ensured. Furthermore, since the engine oil used for lubricating the transmission 230 is splashed on the starter 260, the lubricity of the starter 260 can be improved.

As mentioned above, although this invention was demonstrated with various embodiment, this invention is not limited only to these embodiment, A change etc. are possible within the scope of the present invention.
For example, in the present embodiment, the case where a motorcycle is applied as a saddle-ride type vehicle has been described.
Further, the transmission device 230, the gear shift mechanism 240, and the starting device 260 are not limited to the configuration of the above-described embodiment, and can be appropriately changed. For example, various known configurations can be applied to the shift cam 244 and the shift fork 251. Further, the number of shift pins 248 provided on the shift cam 244 and the number and shape of the cam grooves 246 are not particularly limited. These are appropriately set according to the configuration of the transmission gear 235 and the like.
Further, in the present embodiment, two cases in which the start gear has the first idle gear 269 and the second idle gear 270 have been described. However, the present invention is not limited to this case, and there may be one. There may be more than one.

  DESCRIPTION OF SYMBOLS 100: Motorcycle 101: Main frame 113: Shift change pedal 116: Rear wheel 117: Drive chain 118: Driven sprocket 128a, 129a: Shaft hole (suspension part) 200: Engine 201: Crankcase 202: Cylinder block 203: Cylinder head 204: Cylinder head cover 210a, 210b: Shaft hole 211: Crank shaft 212: Primary drive gear 230: Transmission device 231: Counter shaft 232: Primary driven gear 233: Clutch 234: Drive shaft 235: Transmission gear 236: Drive sprocket 240: Gear shift Mechanism 242: Shift arm 244: Shift cam 246: Cam groove 247: Stopper plate 250: Shift cam strike 251: Shift fork 260: Starter 261: Starter motor 262: Output shaft 264: Torque limiter 265: Shaft 266: First transmission gear 267: Second transmission gear 268: Shaft 269: First idle gear 270: Second idle gear 271: Shaft

Claims (8)

A crankshaft,
A countershaft through which rotation of the crankshaft is transmitted via a clutch;
A drive shaft coupled with a drive sprocket on which a rotation of the counter shaft is transmitted via a plurality of transmission gears and a drive chain for transmitting a driving force to the rear wheels is wound;
A shift cam for changing a combination of the plurality of transmission gears via a shift fork;
A crankcase that rotatably supports the crankshaft, the countershaft, the drive shaft, and the shift cam;
A cylinder block disposed to be tilted forward in the crankcase;
A starter motor disposed behind the cylinder block and forcibly rotating the crankshaft via a start gear;
A straddle-type vehicle equipped with an engine having
In side view,
Axis of the shift cam, the a axis of the crankshaft, the axis of the drive shaft, a straddle-type, characterized in that disposed inside the triangle area whose vertices the axis of the output shaft of the starter motor vehicle. A shift arm that swings in response to a shift operation by an occupant and rotates the shift cam;
A shift cam stopper for positioning the rotation position of the shift cam rotated by the shift arm,
In side view,
The straddle-type vehicle according to claim 1 , wherein the start gear overlaps at least one of the shift arm and the shift cam stopper. In side view,
The straddle-type vehicle according to claim 2 , wherein the start gear overlaps with a swing range of the shift arm. A torque limiter is provided between the starter motor and the starting gear,
In side view,
The axis of the shaft of the starting gear is disposed on the front side of the axis of the shaft of the torque limiter,
The straddle-type vehicle according to any one of claims 1 to 3 , wherein the shaft of the starting gear and the shaft of the torque limiter are connected to each other by transmission gears attached to the shaft. . The straddle-type vehicle according to claim 4 , wherein the transmission gear pivotally attached to the shaft of the starter gear and the transmission gear pivotally attached to the shaft of the torque limiter have the same diameter. . The starting gear has a first idle gear and a second idle gear,
In side view,
The straddle-type vehicle according to any one of claims 1 to 5 , wherein the second idle gear is disposed below the cylinder block in the cylinder axis direction. In side view,
The straddle-type vehicle according to any one of claims 1 to 6, wherein the countershaft is disposed outside the triangular area. A torque limiter is provided between the starter motor and the starting gear,
The starting gear has a first idle gear and a second idle gear,
In side view,
The straddle-type vehicle according to any one of claims 1 to 3 , wherein an axis of the shaft of the first idle gear overlaps with the torque limiter.

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