Helical and Bevel gears are 98.5% per gear stage
1-stage (98.5%), 2-stage (97%), 3-Stage (95%), 4-Stage (94%), 5-Stage (92%)

For worm and helical-worm reducers see the catalog for the efficiency.
Wire Rope - per complete contact around the drum (90 - 95%)
V-Belts - per complete wrap (88 - 93%) / Toothed Belt - per complete wrap 90 - 96%)
Toothed Belt - per complete wrap (90 - 96%) / Chains - per complete wrap (90 - 96%)
Chains - per complete wrap (90 - 96%) / Polymer Belts - per complete wrap (81 - 85%)
Rubber Belts - per complete wrap (81 - 85%)
Overall Efficiency
Variables   Units
ηG Gear efficiency %
ηL Driven unit efficiency %
nT Overall efficiency %