THE PARTS PACKAGE
In addition to the motor specification difference, the
S model has e-bike-specific Continental Top Contact II
26x2.0 tires rather than the Schwalbe Big Ben 26x2.15s,
and Tektro Dorado hydraulic disc brakes rather than
Magura. And, of course, there is that electric green
color. While we found it pleasant, we like it most for the
added visibility it adds the bike.
With the standard ST1 you get the bike without
fenders, but you have the option of two city kits that
include lights, excellent fenders and the Racktime rack.
The basic city kit runs $360, but with a powerful and
effective Supernova E3 light, the kit price rises to $475.
Fenders and the Supernova lights are standard on the
ST1 S, but our bike was delivered without fenders.
While the ST1 S uses a standard-issue Shimano XT
rear derailleur, it is completely unique in the front half
of the drive system. In place of the normal crankset,
chainrings and derailleur is a Schlumpf Speed Drive
System. Schlumpf drives were originally designed
and manufactured in Switzerland, but are now
manufactured by Haberstock Mobility in Germany. The
Schlumpf uses a single front chainring with a planetary
gear assembly behind it. Heel-actuated push buttons
on each side of the crank axle allow the rider to easily,
quietly and reliably shift between high and low range.
With the Speed Drive version, the high ratio is 2. 5
times the low ratio. The Schlumpf system allows a
compact front chainring and low gearing for climbing
with a hugely high ratio for riding fast. The ST1 S has a
32-tooth chainring, so the high range is the equivalent
of an 80-tooth front chainring! Combining the Speed
motor spec with the ultra-high gearing is genius.
To make the Schlumpf system easier to shift, the
Stromer uses thin metal plates over the crankarms
and the heel-shifting buttons. Click the crank into high
range and you are completely comfortable pedaling
at 28 mph. If you have the strength, you could easily
pedal the bike even faster. Obviously, an actual
80-tooth front chainring would cause ground clearance,
derailleur and chain-length issues that the Schlumpf
completely avoids. The convenience is not inexpensive.
The crankset is in the $700 range if purchased