Two e-bikes can both say 48V and 750W and still sit $600 apart on price, and neither listing has to be lying. The trouble is that a spec sheet puts measurements, arithmetic and marketing in the same font.
Open three e-bike listings and you will see the same handful of numbers: 750W, 48V, 15Ah, 1000W peak, up to 45 miles. Some of those are measurements. Some are math you are expected to do yourself. A few are sales copy.
This guide sorts them out: how volts and amp-hours become watt-hours, why rated and peak power are not the same promise, and how to turn a range claim into something you can plan a commute around. Two of our own bikes serve as worked examples, the Storm and the Pegasus Lite, with numbers taken from their product pages on snapcycle.com in October 2026. We sell those bikes, so read the examples as our own listings, not an independent test. The method works on any brand.
If you only keep three numbers from this page, keep these: watt-hours for battery size, rated watts for the motor, and the class with its assisted speed limit.
Battery numbers: volts, amp-hours and watt-hours
The three battery numbers are tied together by one line of math: watt-hours equal volts times amp-hours. Once you can do that multiplication, you can compare any two batteries.
Volts (V)
Voltage is the electrical pressure of the pack. Common e-bike packs run 36V, 48V or 52V, and the motor and controller are built around one voltage. A bigger number does not by itself mean a faster bike or a longer range. It tells you how the system is built, not how much energy is on board.
Amp-hours (Ah)
Amp-hours measure charge capacity, and the figure means little without the voltage beside it. A 36V 14Ah pack and a 48V 14Ah pack share the same amp-hours, but the first holds 504Wh and the second 672Wh. That is a third more energy from the same Ah number.
Watt-hours (Wh)
Watt-hours are the size of the fuel tank, and the one battery number you can compare across any two bikes. Many listings skip it. When they do, multiply. The Storm and the Pegasus Lite each list a 48V 15Ah battery, so 48 x 15 gives 720Wh. (The pages list volts and amp-hours. The watt-hour figure is our arithmetic.)
Look for the cell maker too. The Storm and Pegasus Lite pages name EVE 25P 18650 cells. A listing that names the cells gives you something to look up. If a listing says nothing about them, ask.
Motor power: rated watts vs peak watts
Motor wattage is where listings have the most room to stretch, because the same motor can honestly carry two different numbers.
Rated power
Rated power, sometimes called nominal or continuous, is what the motor is built to deliver without overheating. It is the number to compare between bikes. Federal product-safety law defines a low-speed electric bicycle as one with fully operable pedals, a motor under 750 watts (1 horsepower), and a motor-only top speed under 20 mph with a 170 lb rider. States write their own riding rules, many with a 750W cap of their own, and the wording differs from state to state, so read yours.
Peak power
Peak power is what the motor and controller can push for a few seconds, usually pulling away from a stop or starting up a steep pitch. It is real, and it does add headroom. It is not a number you get to use for a whole climb. The Storm page lists a 750W motor with a 1056W peak. Divide 1056 by the 48V battery and you get about 22 amps, a reminder that peak power is mostly a statement about how much current the controller allows.
The Pegasus Lite page lists a 500W motor and no peak figure, which is fine. A peak number printed large with the rated number nowhere to be found is the warning sign.
Torque
Torque, measured in Newton-meters, tells you how hard the motor pushes at low speed, which is what you feel on a climb or a loaded start. Two 750W motors can feel different on a hill, and listings give torque less often than they should. If your route has steep pitches, ask for it. For 250W, 500W and 750W on real roads, see our motor power comparison guide.
Range claims: turning watt-hours into a number you can plan with
An up to range figure is the ceiling, measured under friendly conditions: a lighter rider, low assist, flat ground, mild weather. It is not a lie. It is also not what you will see on a normal Tuesday.
You can sanity-check any claim with one division: miles equal watt-hours divided by watt-hours used per mile. The Storm and Pegasus Lite descriptions both say up to 45 miles with pedal assist and up to 30 miles on throttle alone, on that 720Wh pack. Work backward:
- 720Wh over 45 miles is 16Wh per mile (pedaling along, low assist)
- 720Wh over 30 miles is 24Wh per mile (throttle only)
That gap is the useful part. How much you pedal changes consumption by half. When you plan a route, use the throttle-only figure as your working number and count the pedal-assist miles as a bonus.
What moves the number
Rider and cargo weight, assist level, speed, hills, stop-and-go riding and tire pressure all move it. So does temperature: cold cuts usable capacity, and heat is hard on the pack over time (see our guide to protecting your battery in summer heat). For a longer look at why real-world numbers land below the label, read our real-world range guide.
The rest of the sheet: class, weight, payload and charger
Class and speed limit
Many US states sort e-bikes into classes by assisted speed and throttle. Snapcycle e-bikes are Class 2: a thumb throttle is allowed, and motor assist cuts out at 20 mph. A speed number with no class is half a sentence.
Weight and payload
Read bike weight and payload together. The Storm lists 78.3 lb and the Pegasus Lite 76.7 lb, and both list a 330 lb total payload. Definitions vary: some brands count only rider and cargo, others include the bike. Ask which one the number means. Heavier riders can also read our guide for heavier riders.
Tires and brakes
Tire size is two numbers, wheel diameter and tire width. The Storm lists 20 x 4 inches and the Pegasus Lite 26 x 4.0, so both are fat tire bikes on different wheel sizes. A smaller wheel makes a bike more compact and quicker to turn. A larger wheel rolls over bumps with less effort. How 4-inch tires behave on loose ground is covered in our beach riding guide.
Charger and charge time
Charger output sets your schedule. A 2A charger on a 48V pack delivers a bit over 100 watts, so 720Wh takes about 7 hours, in line with the 7 to 8 hours the Pegasus Lite lists. That fits overnight charging. If you need quick top-ups between trips, check charge time before you buy.
Worked example: Storm and Pegasus Lite side by side
Same method, two real listings. Figures come from each product page in October 2026, and pages can change, so check the current listing.
| Spec | Storm | Pegasus Lite |
|---|---|---|
| Price | $1,999 | $1,599 |
| Rated motor power | 750W | 500W |
| Peak motor power | 1056W | Not listed |
| Battery | 48V 15Ah, EVE 25P 18650 cells | 48V 15Ah, EVE 25P 18650 cells |
| Watt-hours (48 x 15) | 720Wh | 720Wh |
| Listed range | Up to 45 miles pedal assist, up to 30 miles throttle only | Up to 45 miles pedal assist, up to 30 miles throttle only |
| Class and assist limit | Class 2, 20 mph | Class 2, 20 mph |
| Weight | 78.3 lb | 76.7 lb |
| Total payload | 330 lb | 330 lb |
| Tires | 20 x 4 inch | 26 x 4.0 inch |
| Suspension | Front and rear | Front fork |
Both bikes carry the same battery and make the same range claims, so neither goes meaningfully farther than the other on paper. The $400 difference buys a bigger rated motor (750W against 500W), a 20-inch wheel instead of a 26-inch one, and rear suspension on the Storm. If your routes are flat or rolling, the Pegasus Lite's 500W motor may be enough. If you climb long grades or ride near the payload limit, the extra rated power on the Storm gives you more headroom.
Our comparison of fat tire e-bikes under $2,000 sets all three of our fat tire models side by side, including the S1 folding bike.
A five-minute spec-sheet check
- Multiply volts by amp-hours to get watt-hours. If the listing already shows Wh, check that it matches.
- Find the rated motor power. Treat peak as a bonus.
- Find the class and the speed at which assist stops.
- Read the range claim and note its conditions. If none are given, ask.
- Check payload and what it includes, then weight, charger output and charge time.
Habits worth a second look
- Peak watts in the headline with no rated figure anywhere
- Amp-hours with no voltage, or no way to work out watt-hours
- A range claim with no conditions attached
- No cell maker named
- Two parts of the same listing that disagree, such as the title and the spec table. Ask which one is right before you buy.
- A top speed with no class
None of these makes a bike bad. Each is a question to put to the seller, and how quickly and clearly they answer is part of what you are buying.
Frequently asked questions
How many watt-hours do I need?
Work from your longest normal day. Using the 16 to 24Wh per mile spread from the math above, a 20-mile day needs roughly 320 to 480Wh. Those figures come from best-case claims, so lean toward the high end and leave a reserve.
Is a higher voltage battery better?
Not on its own. A 52V pack with a small amp-hour number can hold less energy than a 48V pack with a large one: 52V x 10Ah is 520Wh, while 48V x 15Ah is 720Wh. Compare watt-hours. Voltage matters inside the bike, but it is not a score.
What does peak power mean on an e-bike?
Peak power is the most the motor and controller will deliver for a few seconds, such as pulling away from a stop or starting up a steep pitch. Rated power is what the motor sustains. The Storm, for example, lists 750W rated and 1056W peak. Compare bikes on rated power.
Does a 750W motor mean a faster e-bike?
No. Assisted speed is set by the bike's class and its limiter. Snapcycle e-bikes are Class 2 with assist that stops at 20 mph, whichever motor they carry. Motor wattage changes how well the bike holds that speed on a climb or under load.
Why do I get less range than the label says?
Labels state a best case. Heavier loads, higher assist, hills, wind, low tire pressure and cold all raise the watt-hours you use per mile. Plan with the throttle-only number, then measure your own: if a 12-mile ride used about 40% of a 720Wh pack, that is roughly 288Wh over 12 miles, or 24Wh per mile. Battery percentages on a display are approximate, so average a few rides.
Looking at a spec sheet and not sure what a number means? Send it to our team through the contact page on snapcycle.com and we will walk through it with you, whichever brand it is. You can also read the full Storm, Pegasus Lite and S1 product pages.