For hills, compare the whole route and load before comparing gear counts. More gears can provide more selectable combinations, but they do not establish motor torque or the easiest available ratio. Battery Wh describes stored energy, not the force available on the steepest section.
Record the difficult part of your route
| Record | Why it matters | Useful evidence |
|---|---|---|
| Climb length and slope | Brief ramps and long climbs impose different demands | Route profile and an actual ride where possible |
| Starts on the slope | Traffic stops can change the difficulty | Junction locations and safe restart space |
| Rider and luggage load | Load affects required effort and handling | Measured load within confirmed limits |
| Surface and return descent | Traction, braking and control matter too | Surface condition and visibility |
Use slope values only when the mapping or measurement method is understood. No maximum climb angle is promised for these models here. Do not convert marketing hill claims into permission to climb under every load and condition.
What the ARSK gearing descriptions mean
XT90 and GT900 list Shimano 21 speed gearing. GT300 and SU7 list Shimano 7 speed. F6 Pro lists single speed. X5's supplied gearing remains unconfirmed. Gear count is not the same as gear range: you need chainring and rear sprocket sizes to compare the lowest ratios properly.
On the confirmed rear hub models, bicycle gears change the rider's pedaling ratio. The motor does not gain the same chain driven gear reduction as mid drive systems. That is why adding gears should not be described as adding motor power.
Use gears before pedaling becomes difficult
- Somewhere safe, learn which controls select easier gears on your actual bike.
- Before the climb, change towards an easier gear while continuing to pedal lightly.
- Avoid forcing shifts while pressing hard on the pedals. If changing on the climb, reduce pedal pressure as conditions safely allow.
- Choose comfortable pedaling effort rather than struggling in an unnecessarily hard gear.
- Before stopping, select an easier gear where it is safe to do so, helping the next start.
These general derailleur principles follow Trek's shifting guidance. They are not model specific control instructions or electrical repair procedures. Follow the instructions supplied with your bike.
Example: Compare the route, not the number
Suppose your commute includes one short ramp immediately after traffic lights and another longer climb later. Record the restart location separately from the long climb. During an appropriate test, assess controlled starting, comfortable pedaling and the descent. Do not conclude that 21 gears will solve the restart simply because seven felt difficult on another bike.
Know when to stop
If pedaling becomes uncontrolled, the bike loses traction, braking feels ineffective or the drive system displays warnings, stop somewhere safe and follow the instructions. Walk or choose another route when the climb exceeds your ability or the bike's permitted use. More assistance is not the right answer to every situation.
For repeated demanding climbs, obtain route relevant information about the complete bike before ordering. Our motor layout guide explains the mechanical difference without promising unsupported climbing performance.
Sources and Scope
Checked 28 October 2026. Requirements depend on the location, system and service described.
