Operator Comfort. All Yamaha midranges F40~F90 are compatible with our award-winning Multi-Function Tiller Handle. Its ergonomic design features Variable Trolling Speed (VTS™), allowing you to adjust trolling in 50-RPM increments with the touch of a button. For added security, the factory-equipped handle on the F40 tiller model features an LED light that signals overheating or low oil pressure conditions. The F25 also features a factory-equipped handle on tiller models.