The 2 references without contexts in paper A. Krutashov V., E. Baulina E., А. Круташов В., Е. Баулина Е. (2016) “Методы снижения усилий в синхронизаторе при включении передачи // Methods for Reducing Effort Exertion in a Gearbox Synchronizer During Shifting Process” / spz:neicon:technomag:y:2014:i:2:p:242-255

Sift System Components in Manual Transmissions. Automotive Product Information API. INA 2009.
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71%). The remainder of the paper shows the ways to decrease said second force peak. Recommendations for synchronizers design improvement are given as well. The conclusion has been made that technical requirements for modern synchronizer design, apart from the maximum synchronization effort, must provide relative maximum value of the second peak of at most 1/3 of synchronization effort. This will ensure improved perception of the shifting process.
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