The wide 2.5 reduction ratio can offer an effective chainring size that is lower than any available chainring (depending on physical chainring selection).
The Schlumpf Mountain Drive also has the highest running efficiency of Schlumpf's offerings, making it the best choice for HPV's or other land-speed vehicles.
It is not recommended to use the Mountain Drive with the Rohloff SPEEDHUB 500/14 due to conflicts with Rohloff's minimum gear ratio requirement.
+ 2.5 reduction ratio
+ Large physical chainring and smaller effective chainring size in reduction mode
+ Offers lowest gear ratio option of Schlumpf gearing systems
+ Highest running efficiency of Schlumpf gearing systems
+ Possibility of an effective chainring size that is smaller than any available chainring
+ 110mm and 130mm BCD spiders can be used with two chainrings
+ Optional steel spider for heavy duty use on tandems and cargo bikes
+ Best when combined with a gear hub or rear cassette offering at least 250% range