Range anxiety sells big batteries. Math buys the right one. Here's how to size it.
The range formula
Step 1: Your longest regular ride (round trip, unless you charge at the destination).
Step 2: Add 30% margin (headwinds, detours, battery aging).
Step 3: Divide by 0.65 (real-world vs claimed range).
Result = claimed range to shop for.
Example: 20-mile round trip → 26 with margin → ÷ 0.65 = 40 miles claimed → ~500–600Wh battery.
Real-world range vs claimed range
Treat manufacturer range figures as optimistic. They're typically measured with a light rider, on flat ground, in the lowest assist mode, with no headwind. For planning purposes, assume 60–70% of the claimed range in normal riding.
What drains a battery fastest: high assist levels, hills, headwinds, heavy loads, under-inflated or knobby tires, and lots of stop-and-start riding. What extends it: steady pedaling in a moderate gear, eco/low assist on flats, keeping tires at proper pressure, and smooth starts. If range anxiety is your thing, the honest fix is a bigger battery (600Wh+) or a bike with an optional range-extender pack — not a bigger motor.
Range by use case
- Short commute (under 10 mi round trip): 400Wh plenty
- Standard commute (10–20 mi): 500–600Wh
- Long commute (20–35 mi): 600–750Wh or workplace charging
- Trail riding (2–4 hrs): 625Wh+
- Cargo/family hauling: 600Wh+ (loads drain fast)
Frequently asked questions
Is a bigger battery always better?
No — bigger means heavier and pricier. Right-sized beats oversized for handling, stairs, and cost.
