| 摘要 |
The device includes a positioning mechanism which is provided with a first end engaging portion for setting the low speed change stage, a second end engaging portion for setting the high speed change stage, and at least one intermediate engaging portion for setting the middle speed change stage. The device also includes an engaging member engageable with one of the engaging portions. In operation, a derailleur is actuated by the forward operation of a lever body of the speed control device to pull a control wire, and backward operation of the lever body loosens the control wire. The positioning member is provided with a displacement engaging portion which is in continuation of the intermediate engaging portion and is displaced in the direction of forward operation of the lever body with respect to the intermediate engaging portion. As a result, a chain guide of the derailleur can be positioned within a stable region with respect to each sprocket of a multistage sprocket assembly when the lever body is operated forwardly and backwardly. |
