Snowmobiles are often operated at high speeds and over rough terrain such as slopes and hills. In such conditions, it is especially important that a rider of a snowmobile be able to maintain effective control of the snowmobile.
When the rider of the snowmobile is crossing a slope, or making a high-speed turn, it is desirable for the rider to shift his weight on the snowmobile to lean uphill or into the turn as much as possible while maintaining effective control over the snowmobile. These positions are also referred to right side hilling or left side hilling depending on which side of the snowmobile the rider shifts his weight. To that end, mountain straps of various types have been devised that allow the rider to remove the downhill or outside hand from the handlebar of the snowmobile and to put it on the strap in order to shift his weight as much as possible uphill or into the turn.
Under normal riding conditions the rider steers the snowmobile by grabbing grip portions located at each end of a handlebar. Adjacent to one of the grip portions, usually the grip portion on which the rider positions his right hand, is located a throttle lever that provides control to the rider over the load of the engine. Such throttle lever is usually referred to as a right throttle lever. An example of a right throttle lever can be found in U.S. Pat. No. 4,899,610, issued Feb. 13, 1990, the entirety of which is incorporated herein by reference. Under normal riding conditions, the right throttle lever is actuated by the right thumb of the rider while the other fingers of the same hand grasp the grip portion of the handlebar. The right throttle lever can also be activated by one or more fingers of the right hand when the rider is leaning toward the right side of the snowmobile with his left hand on the left handle or on the mountain strap.
While the right throttle lever mentioned above is well suited for straight ahead driving on level ground, right turns, left turns and also for right side hilling, it is not well located for the driver to actuate it during left side hilling (i.e. when the rider is leaning toward the left side of the snowmobile). When such a situation arises, the rider must either compromise his stance by leaning only as far as his reach will allow him or tilt the snowmobile into the slope so that the snowmobile and rider are generally horizontal and the rider once again has sufficient reach to operate the right throttle lever since the rider must keep his right hand on the right throttle lever. Further, mountains straps, although designed to improve control during such situations do not completely overcome the problem during left side hilling. Since the rider must keep one hand on the right side of the handlebar to actuate the right throttle lever, the driver can only use his left hand to grab the mountain strap thereby limiting him in positioning his body toward the left side of the snowmobile.
In an attempt to address this problem, additional throttle levers to be installed on the left side of the handlebar have been devised. Such additional throttle levers are usually referred to as left throttle levers, by opposition to the right throttle levers that are usually installed on the snowmobile by default. A typical left throttle lever comprises a lever pivotally mounted on a housing to be installed on the handlebar of the snowmobile. When installed, the lever extends from its pivot point toward the left of the snowmobile, generally symmetrically with the lever of the right throttle lever with respect to the steering axis of the snowmobile. While left throttle levers address partially the problem of left side hilling, they still present several drawbacks.
Because a brake lever is usually located on the left side of the handlebar, the place to position the left throttle lever is limited and causes inconveniences while riding the snowmobile under normal conditions during which the left throttle lever is not needed. In addition, because the left throttle lever and the brake lever are designed to both be actuated by the left hand, it can be difficult for the rider to activate both with the same hand. Also, the design of the left throttle lever is such that the rider has to grab the mountain strap with the right hand and control the left throttle lever with the left hand when left side hilling.
Therefore, there is a need for a throttle lever for a snowmobile that allows good control of snowmobiles during side hilling while not compromising riding of the snowmobile under normal conditions.