Transmission system and method of operation to accommodate engagement of centrifugal clutch

A vehicular transmission system comprising a prime mover, a transmission having at least one mode of operation where the transmission is selectively shifted into a lower gear ratio as vehicle speed decreases, a master friction clutch for drivingly connecting the prime mover to the transmission, and at least one control unit for receiving an input and processing the input according to logic rules to issue an output to system components including at least the transmission, the system further characterized by:

• the master friction clutch being a centrifugally operated clutch;
• the control unit, in the at least one mode of operation, selectively prohibits the transmission from being shifted into a lower gear ratio;
• at least one input corresponding to a system operating condition, wherein the system operating condition is clutch engagement status;
• the control unit including logic rules that control operation of the transmission in response to the system operating condition;
• and
• at least one output corresponding to a command to prohibit the transmission from being shifted into a lower gear ratio in response to the system operating condition.

A vehicular transmission system comprising a prime mover, a transmission having at least one mode of operation where the transmission is selectively shifted into a lower gear ratio as vehicle speed decreases, a master friction clutch for drivingly connecting the prime mover to the transmission, and at least one control unit for receiving an input and processing the input according to logic rules to issue an output to system components including at least the transmission, the system further characterized by:

• the master friction clutch being a centrifugally operated clutch;
• the control unit, in the at least one mode of operation, selectively prohibits the transmission from being shifted into a lower gear ratio;
• at least one input corresponding to a system operating condition;
• the control unit including logic rules that control operation of the transmission in response to the system operating condition;
• and
• at least one output corresponding to a command to prohibit the transmission from being shifted into a lower gear ratio in response to the system operating condition;
• wherein the control unit includes logic rules that determine whether the master friction clutch is engaged or disengaged during the at least one mode of operation and issue a command output that prohibits the transmission from being shifted into a low gear ratio if the master friction clutch is engaged.