ZOONLAI UrbanX Review 2026: $339.99, 504 Wh, 58 lb

City commuter on 24-inch wheels · one geared hub motor, "500W Rated Power" in Smartravel's table · 48 V 10.5 Ah, 504 Wh in the frame · 22 to 24 mph published · 58.37 lb · 330 lb payload · 60 N·m · suspension fork · mechanical disc brakes · 24 × 2.0 tires · Shimano 7-speed · $339.99 · verified September 28, 2026

Quick Answer — The ZOONLAI UrbanX is a $339.99 city e-bike: a 500 W rated geared hub motor, a 504 Wh pack built into the frame, 24 × 2.0 tires on a suspension fork, and 22 to 24 mph published. Held at 15 mph on the throttle alone across level ground, one charge takes a 180 lb rider about 34 miles.

Pedal lightly at that speed and the same charge lasts about 58 miles; at 20 mph on the throttle it lasts about 23. The range section works out your own speed, weight and hills, then keeps a quarter of the pack in hand.

Smartravel's and ZOONLAI's FAQs size the UrbanX for riders of about 4'7" to 5'11", while Smartravel's dimension image prints 5'5" to 6'5", so the fit section turns your inseam into a saddle setting for either window. Its 500 W rating sits under the 750 W e-bike line in federal and California law; the class section explains the speed question that decides the rest.

What this review covers

What $339.99 buys · What it is · Will it fit you · The motor · The pack · How far it goes · Brakes and controls · Suspension and tires · Weight and load · Fenders, parts and care · The Mercer fit test · UL · Recalls · The class question · Where to ride it · Green and red flags · The verdict · Checklist · Buying it from us · FAQ · Limitations · The bottom line · References

How we verified this ZOONLAI UrbanX review

The figures come from the UrbanX's page on the two stores its maker group runs, Smartravel's US store and ZOONLAI's, both read on September 28, 2026, with the two stores' dimension images, our listing, 24 owner reviews and the statutes in the class section. Range and fit are computed from those figures, and every formula appears with its inputs.

The method is specification verification: every figure is checked against the maker group's published specification and recomputed, and each traces to one of those pages, a statute, a named owner, or arithmetic on this page. We sell the UrbanX, so weigh the red flags as closely as the green.

Written by Milad Ghobadibeygvand, BScN (Western University, 2014). Corrections: support@redtailebikes.com.

What $339.99 buys

Every row comes from Smartravel's UrbanX page or ZOONLAI's, read September 28, 2026; where the two stores word a figure differently, the row prints both, and Limitations keeps the rest. 48 V × 10.5 Ah is the 504 Wh.

The UrbanX with the rear rack, in Smartravel's studio image.

What the UrbanX is: a 24-inch city bike with its battery in the frame

The UrbanX is the lightest of the six Smartravel bikes we sell: 58.37 lb on 24 × 2.0 tires, with a sloping top tube, a 504 Wh pack hidden in the frame and a geared hub motor. Smartravel's page calls it "an affordable e-bike made for everyday adventures", and ZOONLAI's describes a bike for "daily commuting, weekend city cruising, light off-road adventures, and family rides".

You order it with or without a rear rack, and the listing also sells two bikes together.

The UrbanX with its rack on grass under trees, in ZOONLAI's photograph.

The two stores belong to one group. ZOONLAI's home page says Zoonlai and Smartravel "are part of the same company", and the US trademark records name two Huizhou companies: ZOONLAI, registration 7,682,289, is held by Huizhou Zhonglai Technology Co., Ltd., and SMARTRAVEL, registration 7,533,630, by Huizhou Zhongmeng Zhixing Technology Co., Ltd. Our Smartravel brand profile sets the UrbanX beside the group's other five.

The owners' words are the warmest part of the record. Among 24 reviews on ZOONLAI's page, 21 of them also on Smartravel's, Thomas wrote that "The motor has plenty of power to get you moving, and assembly was straightforward," and Robert Christian that it "makes easy work of the hilly terrain I ride" (ZOONLAI's page).

Jock Anderson, newly retired with "a 9 mile bike path that goes by my house to the beach", wrote that "for an entry level bike it really is a great bike".

Will the ZOONLAI UrbanX fit you?

The UrbanX has one 24-inch frame and a seat post you adjust, so fit comes down to where you set the saddle, and the group prints two rider windows: about 4'7" to 5'11" in both stores' FAQs, and 5'5" to 6'5" on Smartravel's dimension image. No crank length, seat-post range or grip position is published, so this section prints the formulas' saddle distances for your inseam, nothing measured off the frame.

The table runs the US Army's 6,068 measured bodies through the formula at each height, from 4'11", the shortest height the survey holds enough bodies for, to 6'4".

Three steps give you your number:

1. Take your inseam: stand barefoot against a wall, pull a hardback book up snug between your legs, and measure from the floor to its spine.
2. Find your row in the saddle table and check that your inseam falls inside its range; a longer inseam reads like the next row down.
3. Set the saddle on delivery to your row's distance, then fine-tune with the heel check.

Smartravel's dimension drawing, cropped below its legend. Line D is its "Seat Height 24.02"/61cm", from the saddle's top to the crank spindle, and line B its "Handlebar Height 35.43"/90cm"; ZOONLAI's version of the drawing prints 4'7" to 5'11" as the recommended height.

How high should the saddle go?

For the median rider at each height, the formula puts the saddle's top 30.6 inches above the pedal axle at 4'11", 35.6 at 5'8" and 41.0 at 6'4". It sets the saddle at 109% of your inseam from the pedal axle (Peveler et al., 2005), inside a published band that reaches from 106% to 110.4% (Ferrer-Roca et al., 2012).

Measure it the way Peveler and colleagues did, from the saddle's top to the center of the pedal axle with the crank pointing down along the seat post, and you can check it at home without knowing the crank's length.

For the median rider at each height, the saddle's top above the pedal axle at 109% of inseam and at the band's two ends, 106% and 110.4%. US Army survey bodies, women and men together; the inseam column runs from the 5th to the 95th percentile rider at that height.

The drawn seat gives a second check. Both dimension images draw their "24.02"" line from the saddle's top to the crank spindle, which is where LeMond's 88.3% of inseam measures from: the median rider needs 24.8 inches at 4'11", 28.8 at 5'8" and 30.3 at 5'11".

At every height in the table the median rider's LeMond distance sits above the drawn 24.02 inches, so the median rider at every height raises the saddle above its drawn position.

How far the post rises above that drawn position is not published. Ask us with your inseam before you order and we will get the post's range from Smartravel in writing.

Will my feet reach the ground at a stop?

The UrbanX's top tube runs down from the head tube to the seat post, so at a stop you slide forward off the saddle and stand over the tube with both feet down. No standover height is printed on either store, so no clearance is computed here.

One owner gives a data point. Thomas, 5'6", wrote on ZOONLAI's page: "I can comfortably stand over the top tube—with not much room to spare."

The UrbanX without the rack, in Smartravel's studio image: the top tube runs down from the head tube to the seat post.

Will I feel cramped, or stretched out?

No grip position, stem length or seat angle is published for the UrbanX, so no lean angle is computed for it. The dimension images print a "Handlebar Height 35.43"/90cm" from the ground, and ZOONLAI's page credits the bike with an "adjustable riding position".

A bar you can reach with your back near vertical is the comfortable one. Given three trunk angles to try, twenty recreational cyclists rated the most upright of them the most comfortable (Priego Quesada et al., 2017).

How much weight goes on my hands?

Sitting upright puts little of your weight on the grips, and with no published grip position the UrbanX's share is not computed. For scale, a lab study had ten road racers ride with their hands on the brake hoods, and 15% of their weight went through the bars (Carahalios, 2015).

If your palms tingle on longer rides, sit taller and wear padded gloves: Slane and colleagues measured palm pressure over the ulnar nerve falling by 10 to 28% with padding.

How do I set the saddle when it arrives?

Begin at your row's distance and judge the result by the knee: at the bottom of the stroke it should keep a bend of 25 to 35 degrees (Peveler et al., 2007). The heel check gets you close: rest your heel on the lower pedal and raise the saddle until that leg is just straight, then pedal with the ball of your foot.

Owners describe short builds. Juli M wrote that "Assembly took less than an hour", and L. Walters had "the bike street ready within an hour and a half, alone" (Smartravel's page). Thomas's note on the build is worth keeping: "one pedal has reverse threads".

How we computed fit

The saddle table rests on one rule, the saddle's top at 109% of inseam above the pedal axle, with 106% and 110.4% as the band's ends. No crank length is published for the UrbanX, so the table stays at the pedal axle, and LeMond's 88.3% of inseam gives the crank-axle distance without one.

A worked case: a 5'8" rider whose inseam is the survey's median for that height, 32.6 inches. The formula wants the saddle 35.6 inches from the pedal axle, 34.6 to 36.0 across the band, and LeMond puts it 28.8 inches from the crank axle, above the drawn 24.02.

The survey holds 44 bodies at 4'11" and fewer than 30 at each height from 4'7" to 4'10", too few for a median, so the table starts at 4'11"; Limitations keeps that gap.

A 500 W geared hub motor with 60 N·m

Smartravel's specification table rates the UrbanX's motor at "500W Rated Power", ZOONLAI's calls it "500W continuous power", and both stores' spec strips print "500W Peak Motor", with "60+ N·m" of torque. The range model holds the motor to 500 W, which carries a 180 lb rider at up to 21.0 mph on flat ground on the throttle alone, and 21.4 with easy pedaling.

The rear hub, the cassette and the Shimano derailleur, cropped from ZOONLAI's photograph.

That flat-ground top sits close to the one owner's reading on record: Roger Ellison wrote "Top speed 22 mph with a long lasting battery" (Smartravel's page). ZOONLAI's table gives the 24 mph at "PAS Level 5", the highest pedal-assist setting, where your legs add to the motor.

The Amazon listing for the L24, the UrbanX's model code, under the ZOONLAI brand describes the motor as "48V 350W brushless rear motor (peak 500W)". The range section runs the bike at 350 W as well: the flat miles barely move, while the hill column changes.

The seven Shimano gears serve your legs only. A hub motor turns at the wheel's speed in every gear, and our e-bike motor guide sets hub and mid-drive motors side by side.

A 48 V 10.5 Ah pack in the frame: 504 Wh

48 V × 10.5 Ah is 504 watt-hours, the UrbanX's whole store of energy, in a pack ZOONLAI describes as "seamlessly integrated into the frame". Smartravel's page adds an "integrated Battery Management System (BMS)" that "helps protect the battery and maintain consistent performance".

The frame's down tube, where the pack sits, cropped from ZOONLAI's photograph.

Charging: plan on an evening from empty. The included "48V 2A" charger puts 2 A back into a 10.5 Ah pack, so a full charge takes about 5.3 hours of full current; the FAQ gives "4–6 hours" and the feature copy "4–5 hour". A charger slows as the pack nears full, so the last stretch takes longest.

For the years ahead, ZOONLAI's warranty page says its batteries are "Designed to retain up to 75% capacity after 300 charge cycles", and ZOONLAI's store sells a replacement "ZOONLAI UrbanX L24 Battery" (the parts table).

How far the ZOONLAI UrbanX goes on one charge

On level pavement a 180 lb rider gets about 34 miles from a full charge holding 15 mph on the throttle, about 23 at a steady 20 mph, and about 58 at 15 mph with light pedaling. Up a 4% grade at 10 mph on the throttle, it lasts about 12 miles.

To get your own figure from the tables:

1. Find the speed you cruise at, and how much you pedal, in the first two tables.
2. For every 1,000 feet you climb at 10 mph, add 149 to 195 Wh on the throttle over 4 to 8% grades, or 124 to 187 Wh with light pedaling over 4 to 10% (the hills table).
3. Adjust for your weight and load and the air temperature, then plan with 25% of the pack kept in reserve.

Every row is one steady ride, computed from Smartravel's specification, Bafang's published figures for a comparable hub motor, field-measured rolling resistance for everyday riders' tires and a cycling-power model validated on an open road. The formula subsection works one ride through.

Does riding faster cut range? Miles at each speed

Speed is the biggest lever you control: on the throttle, a charge lasts about 50 miles at 10 mph and about 23 at 20 mph. Air drag's power demand rises with the cube of speed: 20 mph needs (20 ÷ 15)³, or 2.4 times, the air power of 15 mph, which is how 34 miles become 23.

Motor only, on level pavement, 180 lb aboard, air at 77 °F. The model holds the motor to its 500 W rating, enough for 21.0 mph on the flat; above that the speed comes from pedal assist, which ZOONLAI prints as "Up to 24 mph (PAS Level 5)". The right-hand column holds 25% of the pack in reserve.

Light pedaling stretches a charge: 75 W from your legs at 15 mph lifts it from 34 miles to 58. Here light pedaling is 75 W and steady pedaling 150 W; on their own, with no motor, those efforts would carry the UrbanX at about 9.8 and 13.9 mph on level ground.

Miles per full charge, level pavement, a 180 lb rider. Light pedaling at 15 mph draws 8.6 Wh a mile; the throttle alone draws 14.8. The 118- and 166-mile cells have your legs doing most of the work, so they lean hardest on the model's motor losses at light load (Limitations); "legs alone" marks the speed at which 150 W of pedaling leaves the motor nothing to add.

Do pedals or gears save battery on a hub motor?

Your legs save battery; the gears set how fast your feet turn. The hub motor spins at the wheel's speed in every gear, so a shift changes your cadence and leaves the motor's load where it was. At any one speed and grade, the pack's draw falls with each watt you put in:

Watt-hours drawn from the pack per mile, 180 lb aboard, 77 °F; left to right the rider adds nothing, 75 W and 150 W.

On the 8% row, easy pedaling trims the draw from 92.2 Wh a mile to 69.1, and steady pedaling to 50.6. On a 500 W motor your share of a climb is large: every watt you add is one the motor and pack do not have to make, along with the heat they would have shed making it.

How much battery does a climb cost?

Climbing is where a 504 Wh pack goes fastest: at 10 mph on the throttle, each 1,000 feet of 4 to 8% grade uses 149 to 195 Wh more than the same distance on level ground. With light pedaling, 1,000 feet of 4 to 10% grade uses 124 to 187 Wh.

Lifting a 180 lb rider and the 58.37 lb bike 1,000 feet takes 90 Wh at the rear wheel; motor and pack losses make up the rest.

180 lb aboard, throttle only. Speeds in the motor-only column are those the modeled motor sustains at its 500 W limit; the per-mile and full-charge columns assume 10 mph, which the motor alone cannot hold from 10% up.

The steepest grade the UrbanX holds at 15 mph on the throttle is 4.6%. Past that, shift down and pedal: the motor keeps working at a lower speed, and your legs fill the gap.

The UrbanX with its rack on its kickstand beside a tiled wall, in ZOONLAI's photograph.

For a hilly commute, price the flat miles and the climbing separately, then add them. On the throttle, 10 level miles at 15 mph use about 148 Wh and 1,000 feet of 8% climb about 195, 343 Wh in total, inside the 378 Wh left after a 25% reserve.

Does rider weight change the range?

On the flat a few miles; on a climb a great deal. Weight adds to rolling drag and to the work of climbing but not to air drag, which is why heavier riders fall further behind as the grade steepens.

The rider plus everything carried, with the UrbanX's own 58.37 lb in every row because the motor moves it too. Throttle only. Smartravel's FAQ sets the payload at 330 lb, the last row.

Adding weight from 180 to 330 lb shortens a level 15 mph ride from 34 miles to 27. From 220 lb up, the motor alone cannot hold 10 mph up 8%, so heavier riders pedal on steep climbs. Loaded to the full 330 lb, the UrbanX still covers about 27 level miles at 15 mph.

How much range does cold weather take?

The colder the air, the shorter the ride: light pedaling at 15 mph, good for 58 miles at 77 °F, falls to about 43 miles at 32 °F and 39 at 14 °F.

Level ground, 180 lb aboard. Each row's central figure comes from McMaster University's LG HG2 cell data, recomputed for a 0.5C discharge with the cells at air temperature; the lab measured at 77, 50, 32 and 14 °F, and the other rows are interpolated on straight lines between those four. The bracketed values mark what other published cell data would give.

A bracket's floor is the lowest capacity Samsung's data sheets (25R, 30Q, 35E) give at that temperature for a cell drained at one to four times its capacity per hour; its ceiling is the highest energy Casado and colleagues recorded in 2025 at a gentler rate. Neither store names the UrbanX's cells, so the LG cell stands in.

Cold costs range three ways at once. The cells return less energy; air near freezing is about 9% denser, by the U.S. Standard Atmosphere's gas law; and cold rubber rolls harder, which the model takes as 0.5% per °F below 77 °F, a rate between Rothhämel's measurement and Bicycle Rolling Resistance's road-tire average that stops rising below 41 °F.

The 24 × 2.0 tires and the riding position

On the flat the tire is the model's biggest stand-in: no drum in the sources measures the UrbanX's 24 × 2.0 block tread, so the central case is the field average for 138 knobby tires coasted down by everyday riders in Tengattini and Bigazzi's study. The same study's commuter tires set the low end.

Full-charge miles, 180 lb aboard, flat ground. The rows are Tengattini and Bigazzi's field averages for 273 commuter tires and 138 knobby tires, and the knobby average plus one standard deviation. Keep the tires at the pressure printed on their sidewalls: a soft tire rolls like the bottom row.

Posture counts for more as speed rises. The central drag area is Tengattini and Bigazzi's 0.603 m² for 90 everyday mountain-bike riders, the closest of their groups to a bike with a flat handlebar, and their 0.640 m² for 37 upright cruiser riders is the bracket: sitting that upright takes the 20 mph throttle ride from 23 miles to 22.

The group's 23 to 43 miles, matched to steady rides

The maker group prints seven range figures for the UrbanX, and each fits a steady ride on the model. Smartravel's FAQ gives "approximately 23 miles in pure electric mode" and "up to 40 miles with pedal assist"; the pages add "25–40 miles", "35+ Miles" and a gallery banner's "18-23 MILES PURE ELECTRIC", and the Amazon listing under the ZOONLAI brand prints 25–30 and 35–43.

Each band is read at its top. The per-mile figure divides the 504 Wh pack by the group's miles; the speed columns show where the model's level ride, 180 lb aboard, uses exactly that much. "Faster than it can hold" means no steady speed the UrbanX reaches on that effort draws so much.

So the FAQ's 23 miles fits a throttle ride near 20 mph, and its 40 miles fits about 13 mph on the throttle or 17.6 with easy pedaling. The lower ends of the bands, 18 and 25 miles, fit rides with hills, stops and starts, which cost more than any steady flat ride.

Plan on 75% of the row that fits your ride, less on stop-and-go days, so there is margin for a detour or a headwind: 26 of the 34 miles at 15 mph on the throttle, 17 of 23 at 20 mph.

How the range figures are computed

A steady ride in still air needs a steady power at the rear wheel, and Martin and colleagues' model, checked against real riding on an open road in 1998, writes it as one equation:

P (rear wheel) = v × [ m g (Crr cos θ + sin θ) + 0.5 ρ CdA v² ]

In it, v stands for speed, m for the total mass of rider, load and bike, g for gravity and θ for the road's slope. Crr is rolling resistance (0.0092 is a drag equal to 0.92% of the weight on the tires), ρ is the density of the air, and CdA is the drag area, how much frontal bulk the air must move aside. One bracketed term covers tires and grade, the other the air.

Four steps link the wheel to the pack:

1. Your pedaling arrives at the rear wheel through the chain, which delivers 97.7% of it by Martin and colleagues' measurement; the motor covers the rest.
2. The hub motor sits inside the rear wheel and spins at the wheel's speed in every gear.
3. Its behavior is modeled on a comparable motor whose figures are published. The RM G0H0 geared hub in Bafang's 2021 OEM workbook turns at 510 rpm with no load and 426 rpm at its rating, at an efficiency of 80 percent or better. The model keeps that shape, sets the no-load speed at the UrbanX's published 24 mph on its 24.41-inch wheel, runs it at the pack's 48 V and holds it to 500 W.
4. The pack gives up some energy as internal loss, at the rate Arango, Lopez and Ceren measured on a 48 V battery, scaled to the same fraction of capacity.

The pack's draw divided by speed gives watt-hours per mile, and the range is 504 Wh × the fraction the cells still deliver at that temperature ÷ watt-hours per mile.

One ride, worked end to end: 180 lb aboard, 15 mph on the throttle, level pavement, 77 °F. Rider and bike weigh 238.37 lb, 108.1 kg together. Rolling the tires takes 65.4 W at the wheel and pushing through the air 107.6 W, 173.0 W together.

At that speed the 24.41-inch wheel makes 207 turns a minute. Modeled as a DC motor on Bafang's published figures (1.387 N·m of torque per amp, a 0.607 Ω winding, 0.55 A with no load), it supplies that power with 8.0 N·m on 6.3 A. At that point it is 81% efficient and pulls 213.8 W.

Counting the pack's own losses, the cells supply 222.0 W, which is 14.80 Wh per mile at 15 mph: 504 ÷ 14.80 is about 34.1 miles, and 25.5 once a quarter is held back.

Two published benchmarks recomputed, and an owner's top speed set beside the model's. Each half of the model reproduces the figure its source prints, and the one owner's reading on record checks the model's flat-ground ceiling:

The road-physics and motor rows are the model's self-test: it reproduces Appendix I of Martin and colleagues' paper and the RM G0H0's rated point in Bafang's workbook. The top-speed row sets the model's steady flat-ground ceiling against the owner's reading on the owner's own unit, rider weight unstated; the gap is 4.5% at 180 lb.

Two sensitivities bracket the motor. At 82% efficiency in place of Bafang's 80% floor, the 15 mph throttle figure moves from 34 miles to 36. Held to the 350 W in the Amazon listing, it moves to 33 miles, and at 10 mph the motor can no longer hold an 8% grade on its own.

Brakes, lights, display and walk assist

Mechanical disc brakes stop both wheels. Smartravel's page promises "reliable stopping power and precise control" from "high-response mechanical disc brakes", and olivia.wilson, who calls the UrbanX "Perfect for everyday commuting and weekend excursions", lists "responsive brakes" beside the comfortable seat and smooth handling.

The handlebar, the stem, the brake levers and the headlight, cropped from ZOONLAI's photograph.

The lighting and controls come fitted. Smartravel lists a "Bright LED Headlight", and its color LCD handles "the headlight, horn, 7-speed shifting, pedal assist, throttle, and pedal-only modes". Thomas describes the display as "simple and functional", showing "speed, assist level, battery, and the basics".

Walk assist helps with steps and ramps. Thomas's own words: "When I bring mine up a few steps, I simply use the walk-assist feature, and it makes the job easy" (ZOONLAI's page).

A suspension fork on 24-inch wheels

The front is sprung and the rear is rigid. Smartravel's page describes a "High-Performance Suspension Fork" that "absorbs bumps and vibrations", and L. Walters found that "The adjustable front forks can be set for your riding style".

The suspension fork, the front rotor and the fender, cropped from ZOONLAI's photograph.

The wheels are 24 inches with 2.0-inch tires. ZOONLAI's FAQ says that with them, the fork and the Shimano 7-speed, the UrbanX "handles city roads, gravel, sand, snow, and light trails with ease". The fenders are quick-release: Smartravel's copy has you "Lock or release the fenders in seconds" for maintenance.

58.37 pounds, a 330-pound limit, and the other figures

The UrbanX weighs 58.37 lb on both stores, 26.5 kg in ZOONLAI's FAQ, and Smartravel's FAQ sets "The maximum total payload" at "330 lbs, including the rider and cargo". Count the 330 lb for yourself, your bag and whatever rides on the rack; the bike's own weight sits outside it.

At 58.37 lb it is the lightest of the six Smartravel bikes we sell; the next lightest, the DK400, weighs 68.3 lb. Thomas, who brings the bike up a few steps, wrote that "The weight feels well balanced".

Size a garage spot, a car rack or a train platform for a bike 65.75 inches long on a 44.49-inch wheelbase, with the bars 35.43 inches off the ground, in the dimension images. The rear rack is an option you choose at checkout: the rack version is $359.99.

Fenders, parts and care

The fenders are there for wet days. Smartravel's copy promises "reliable protection in changing weather conditions" from the quick-release fenders, and describes the disc brakes' "confident braking" on wet roads. Dry the bike off after a wet ride and charge it indoors.

The UrbanX under a flowering tree beside a building, in ZOONLAI's photograph.

The main parts are listed by the maker. ZOONLAI's store carried these UrbanX parts on September 28, 2026:

Prices as listed on ZOONLAI's store that day, each orderable. Under warranty, a failed part on a bike you bought from us is replaced through us at no cost (buying it from us).

Charge it on the charger in the box, and keep the pack from sitting empty. Charge after rides, top it up during a long lay-up, and store the bike indoors in winter: the cold table shows how a cold pack gives back less.

On ZOONLAI's page, Thomas found "Shimano and other well-known brands" among the components, Joshua Bretherton reported "no complaints" after "almost 160 miles", and Floyd Austin Peek's household has taken theirs "to the grocery store a couple of times" and camping.

The Mercer fit test

Every review we publish runs the same seven people past the machine: the Mercers, a fictional family aged 12 to 63, so the fit answers can be compared across bikes (meet the Mercers).

Each verdict rests on a published figure (the group's two rider windows, the 330 lb payload) or on California law, where the family lives. The saddle figure is the median rider's for that height in the saddle table, measured from the pedal axle.

Jack and Ruth show where the two windows part. At 6'1" Jack is outside the FAQs' 4'7"–5'11" and inside the image's 5'5"–6'5"; Ruth, at 5'5", sits in both. For a rider near either edge, the in-writing post range decides it.

Is it UL certified?

Both stores show a badge titled "UL Certified" with the line "Safety Certified in Accordance with UL 2849", and Smartravel's FAQ answers "Yes. The UrbanX electrical system is certified in accordance with the UL 2849 safety standard." ZOONLAI's FAQ adds "Certified by TUV (UL 2849 standard)".

Smartravel's FAQ ties the certification to the UrbanX's electrical system. If a landlord, a building manager or an insurer asks for the certificate itself, email us: we will request it from Smartravel, naming the model and its code, L24, and forward what comes back.

Has it been recalled?

No. Searched on September 28, 2026, the Consumer Product Safety Commission's recall database held no recall under Smartravel, Smart Travel, Smartravelor, ZOONLAI or ZonMen in the recall title, product name or manufacturer field, and none of 623 bicycle, e-bike, battery and scooter records mentions the brand, "UrbanX" or the L24 model code.

Before its silence was trusted, the search was run on names with known recalls: the same database returned 1 recall for Ancheer, 54 for Specialized and 24 for Trek that day.

The class question: 500 W and 22 to 24 mph

Where the UrbanX may be ridden turns on two published numbers: a motor rated 500 W and a top speed of 22 to 24 mph. Smartravel's specification table gives both, and its display carries a throttle as well as pedal assist.

Start with the federal definition, which 15 U.S.C. § 2085(b) writes this way:

For the purpose of this section, the term "low-speed electric bicycle" means a two- or three-wheeled vehicle with fully operable pedals and an electric motor of less than 750 watts (1 h.p.), whose maximum speed on a paved level surface, when powered solely by such a motor while ridden by an operator who weighs 170 pounds, is less than 20 mph.

California's code is one state's version of the same lines. Vehicle Code § 312.5(a), read September 28, 2026, covers a bicycle with "an electric motor that does not exceed 750 watts of power", then sorts it into three classes by where the help stops:

Sources: the statutes as linked and Smartravel's UrbanX page, read September 28, 2026.

The 500 W rating sits under the power line in both texts; the speed line is the open question. As published, 22 to 24 mph is above the 20 mph at which a California class 2 stops assisting, and the throttle keeps the UrbanX out of California's class 3 wording. Assistance that stops at 20 mph would place it in class 2, and that is the setting to confirm before you ride on public roads.

Your state's code decides which vehicle the UrbanX counts as on a public road and what that asks of you: our 50-state e-bike law atlas prints every state's definitions.

Where you can ride it

Streets, bike lanes and paths as your state's classes allow, and private land with the owner's say-so. On public roads the class decides; a city can also set rules for its own paths, so read the sign at each trailhead.

Federal land managers sort e-bikes by class too. The Bureau of Land Management's definitions reach machines with "an electric motor of not more than 750 watts (1 h.p.)", which takes in the UrbanX's 500 W, in three classes like California's.

The Forest Service goes further: its final e-bike directives of March 31, 2022, recorded at 87 FR 41278, treat "all classes of e-bikes as motor vehicles" on National Forest land. A district's motor vehicle use map then governs, and 36 CFR 261.13 bars riding a motor vehicle "other than in accordance with those designations".

The land manager's rule governs each row; the UrbanX's specification settles none of them by itself.

A National Forest ride off the designated routes falls under 36 CFR 261.1b, which provides for "imprisonment of not more than six months" or a fine under 18 U.S.C. 3571, or both. Our public-land e-bike guide covers each agency in turn.

Green flags / Red flags

Green flags

• 504 Wh for $339.99, computed at about 34 miles at 15 mph on the throttle with 180 lb aboard, or 58 with light pedaling.
• 58.37 lb, the lightest of the six Smartravel bikes we sell, with walk assist for steps and ramps.
• A suspension fork and 24 × 2.0 tires that ZOONLAI says handle "city roads, gravel, sand, snow, and light trails".
• Disc brakes at both ends, with a headlight, a horn and a color display.
• 500 W rated, under the 750 W line in the federal and California texts.
• Two rider windows, 4'7" to 5'11" and 5'5" to 6'5", with the saddle distance for your inseam in the table.
• Parts listed by the maker: a replacement battery, tire, display, headlight and brake pads on ZOONLAI's store.
• No federal recall names Smartravel, ZOONLAI or the UrbanX in the CPSC database.
• UL 2849 on both stores' badges, and "certified in accordance with the UL 2849 safety standard" in Smartravel's FAQ.
• $339.99, matching Smartravel's own store, with free shipping to the lower 48.

Red flags

These are about fit: who the UrbanX is wrong for, and where to go instead.

• Wrong if your streets need a class 2 as set up at the factory. Its published 22 to 24 mph sits above class 2's 20 mph line in the class section; tell us your state and we will get the assist cut-off from Smartravel in writing before you order.
• Wrong for long, steep climbs on the motor alone. From 10% up the motor cannot hold 10 mph by itself (the hills table); our Raptor ST202 review covers a Smartravel with a 1,296 Wh pack and a motor rated 1,200 W sustained.
• Wrong for a rider and gear over 330 lb. Our Smartravel DK400 review covers a Smartravel rated for 350 lb of rider and cargo, at $699.99.
• Wrong if you want 4-inch tires and a bench seat. The DK400 in that review rides on 20 × 4.0 fat tires under a moped-style bench.
• Wrong if you need more than about 26 miles at 15 mph on the throttle after keeping a reserve. Our Rocket ST201F review covers a Smartravel with an 873.6 Wh or 1,228.8 Wh pack.
• Not for riders under 16 as published. At 22 to 24 mph the UrbanX sits above classes 1 and 2, and our 50-state law atlas sets out each state's age rules for younger riders.

Buy it if / Buy something else if

Buy it if you want a light, low-cost e-bike for commuting, errands and paths, you stand within the group's windows, and your rides are mostly flat or rolling, with your legs on the pedals for the steep parts.

For $339.99 you get a 500 W rated hub motor, 504 Wh in the frame, a suspension fork, disc brakes at both ends, a Shimano 7-speed, a headlight and a color display. On Shop Pay the UrbanX comes to 4 interest-free payments of $84.99, or $30.69 a month for 12 months at 15% APR, $368.28 in all, each subject to an eligibility check by Affirm's lending partners.

Robert Christian's verdict on ZOONLAI's page, after research the reviewer calls "exhaustive" for a first e-bike: "the best bike for the money you will find anywhere! Believe me...I LOOKED."

Buy something else if your streets need a class 2 as it comes from the factory (tell us your state and we will match a bike of ours), you climb long steep hills on the motor alone (our Raptor ST202 review), or you and your load weigh over 330 lb (our DK400 review). Our e-bike reviews hub compares every machine we have reviewed on weight, load rating, price and warranty.

Before you buy: the checklist

Ten checks before you spend $339.99; the first two decide where the UrbanX may be ridden.

1. Read your state's definitions in our law atlas, and settle the assist cut-off with us before you order.
2. Check the rider's age against your state's rules for the class the bike is set up as.
3. Take your inseam to the saddle table and note your row's distance.
4. Check your height against both windows: 4'7" to 5'11" and 5'5" to 6'5".
5. Add up yourself and your bag and keep the total at or under 330 lb.
6. Choose the rack now if you will carry groceries; the rack version is $359.99.
7. Find your speed in the range tables, budget three quarters of that row, and add the climbing on your route.
8. Plan where the bike lives: 58.37 lb, 65.75 inches long, near an outlet for the 48 V 2 A charger.
9. Keep the tool kit and the reverse-threaded pedal in mind for a build owners finished in under an hour to an hour and a half.
10. Get a helmet for the speeds you plan to ride.

Buying it from us

Why buy the UrbanX from Redtail

Our listing priced the UrbanX at $339.99 on September 28, 2026, against a $699.99 regular price, the same pair Smartravel's own US store showed. Bought from us, the warranty claim, the shipping and the questions come to one US team, and we deal with Smartravel for you.

Changing your mind is handled separately under our refund policy: the bike has to be unopened in its factory packaging and the return asked for within 72 hours of delivery, with a 15% restocking fee plus the return shipping, and canceling an order costs a 3% transaction fee. Settle the fit, the range and the class with us first, and the order goes in decided.

Two UrbanX bikes, one with the rack and one without, in Smartravel's studio image of the two-bike option.

Frequently asked questions

How far can the ZOONLAI UrbanX go on one charge?

About 34 miles at a steady 15 mph on the throttle over flat pavement for a 180 lb rider, and about 58 if you pedal lightly at that speed; at 20 mph on the throttle it is about 23. Hills of 4 to 8% cost 149 to 195 Wh per 1,000 feet at 10 mph on the throttle, and the range section prices your own ride.

How fast does the UrbanX go?

Smartravel's spec strip prints 22 mph, and its table "Up to 24 MPH"; ZOONLAI's gives the 24 mph at "PAS Level 5", the highest assist setting. On the throttle alone the model holds 21.0 mph on the flat for a 180 lb rider, and an owner reports "Top speed 22 mph".

What motor does the UrbanX have?

A geared hub motor in the rear wheel, "500W Rated Power" in Smartravel's table and "500W continuous power" in ZOONLAI's, with "60+ N·m" of torque. Both stores' spec strips call the 500 W its peak, and the Amazon listing for the L24 under the ZOONLAI brand gives 350 W with a 500 W peak.

How long does the UrbanX take to charge?

The FAQ gives "4–6 hours" on the included 48 V 2 A charger, and the feature copy "4–5 hour". At 2 A a 10.5 Ah pack takes about 5.3 hours of full current, and a charger slows as the pack fills, so plan on an evening.

Is ZOONLAI a real electric bike brand?

Yes. ZOONLAI is a registered US trademark, registration 7,682,289, held by Huizhou Zhonglai Technology Co., Ltd., and ZOONLAI's store sells the UrbanX under a 12-month limited warranty on its major components.

Is ZOONLAI the same company as Smartravel?

ZOONLAI's home page says the two "are part of the same company", and each store sells the other's bikes. The trademarks are registered to two Huizhou companies: ZOONLAI to Huizhou Zhonglai Technology and SMARTRAVEL to Huizhou Zhongmeng Zhixing Technology.

Is the UrbanX street legal in California?

It turns on its speed setting. The 500 W rating is under California's 750 W line, and a class 2 has to stop assisting at 20 mph; the published 22 to 24 mph is above that. We will get Smartravel's written answer on the cut-off for you, and the class section sets out the lines.

What size rider does the UrbanX fit?

Both stores' FAQs give about 4'7" to 5'11", and Smartravel's dimension image 5'5" to 6'5". For a 5'8" rider with the survey's median 32.6-inch inseam, the formula sets the saddle 35.6 inches above the pedal axle; the saddle table gives your row from 4'11" to 6'4".

How heavy is the UrbanX?

58.37 lb on both stores, 26.5 kg in ZOONLAI's FAQ, the lightest of the six Smartravel bikes we sell, and it carries up to 330 lb of rider and cargo. Thomas brings it up a few steps with the walk-assist button.

How hard is the UrbanX to assemble?

Owners report under an hour to an hour and a half, alone, with "Basic tools" in the box for "the handlebar, pedals, front wheel, and optional rear rack". One pedal has reverse threads, and ZOONLAI's installation video shows the build.

Where can I get parts or a battery for the UrbanX?

ZOONLAI's store listed a replacement UrbanX L24 battery at $199.00 on September 28, 2026, with the 24-inch tire, the display, the headlight and brake pads (the parts table). If it fails under warranty and you bought the bike from us, the part comes through us at no cost.

Is the UrbanX UL certified?

Both stores show a "Safety Certified in Accordance with UL 2849" badge, and Smartravel's FAQ says the electrical system "is certified in accordance with the UL 2849 safety standard". For the certificate itself, email us and we will request it from Smartravel (the UL section).

Is the UrbanX a good e-bike under $500?

For flat and rolling commutes it brings 504 Wh, disc brakes at both ends, a suspension fork and a Shimano 7-speed for $339.99, all in Smartravel's specification. On long steep climbs its 500 W motor needs your legs, and the hills table shows where.

Can a teenager ride the UrbanX?

ZOONLAI's page says it suits riders "from teenagers to adults", and in California every rider under 18 wears a helmet on a bicycle (§ 21212(a)); 16 is the minimum age for a class 3 (§ 21213(a)). As published, 22 to 24 mph sits above classes 1 and 2, so read the class section before a younger rider takes it out.

Can I finance the UrbanX?

Yes. On our store Shop Pay splits $339.99 into 4 interest-free payments of $84.99, or $30.69 a month for 12 months at 15% APR, $368.28 in all, each subject to an eligibility check by Affirm's lending partners.

What do owners say about the UrbanX?

Of 24 reviews on ZOONLAI's page, 20 give five stars, three give four and one gives three. Owners praise the power on hills, the build time and the price; Thomas calls it "an excellent value".

What warranty does the UrbanX have?

Smartravel's FAQ gives "a 12-month limited warranty and a 30-day return period", and ZOONLAI's warranty page covers the battery for 12 months with the frame, motor and controller. Bought from us, the claim comes to us, and we file it with Smartravel.

Limitations of this review

Twenty things this review cannot settle, listed so you can weigh them.

1. We sell this bike. Weigh the red flags as closely as the green.
2. This is a specification-verified review. Its figures come from the two stores' UrbanX pages, our own store record, statutes, named owners' own words, the published research the range and fit sections cite, or arithmetic on this page.
3. Each range figure is one steady ride: a single speed on a single grade, no wind, no stops. Stops, starts and headwinds cost more; a tailwind costs less.
4. No ride to an empty battery with its speed, load and terrain stated turned up in the sources read: 24 owner reviews, the maker group's three UrbanX videos and a web search. The range model is checked against the published physics, the comparable motor's rated point and an owner's top speed.
5. Bafang's figures stand in for the UrbanX's motor. The model uses Bafang's published shape with its no-load speed set at the published 24 mph. At 82% efficiency the 15 mph throttle figure moves from 34 miles to 36; held to 350 W, to 33.
6. The motor's rating is printed more than one way. "500W Rated Power" (Smartravel's table), "500W continuous power" (ZOONLAI's), "500W Peak Motor" (both spec strips), and "48V 350W brushless rear motor (peak 500W)" on the Amazon listing for the L24 under the ZOONLAI brand. This review runs 500 W and shows 350 W beside it.
7. Light-load motor losses are modeled, not measured. The physics reproduces Martin and colleagues' worked example and the motor reproduces Bafang's 80% at the rated point; the 118- and 166-mile cells lean hardest on the model's losses at light load.
8. The documents read here do not say how much of the pack the battery management releases. On one measured pedelec, researchers at KIT found 75% used in a standard range test, and the planning column keeps that 25% back.
9. The tire coefficient is a stand-in. No drum measurement of the UrbanX's 24 × 2.0 tire was found, so the model uses the field average for 138 knobby tires, bracketed by commuter tires and by one standard deviation.
10. The cold figures rest on one cell's laboratory data. Neither store names the UrbanX's cells, so the central line uses McMaster University's LG HG2, bracketed by other published cell data, with the cells assumed to be at air temperature.
11. The charge time is arithmetic on the charger's rating. The FAQ quotes 4 to 6 hours and the feature copy 4 to 5; 10.5 Ah at 2 A is 5.3 hours of full current, and a charger's current tapers near full.
12. No crank length, seat-post range, grip position or seat angle is published, so the fit section prints the formulas' distances and no lean, hand load or standover; the post's top is a question for Smartravel in writing.
13. The frame is not measured on the dimension images. Their printed lengths do not reproduce on a single scale, so the fit figures come from the formulas and the published windows alone.
14. The rider windows differ. Both FAQs and ZOONLAI's image print 4'7" to 5'11"; Smartravel's image prints 5'5" to 6'5". The survey behind the fit table holds fewer than 30 bodies at each height from 4'7" to 4'10", so the table starts at 4'11".
15. The fit figures use the US Army's ANSUR II bodies: 6,068 soldiers aged 17 to 58, measured in 2010 to 2012, who are not the US public and include no children, so your own inseam decides your row.
16. The saddle formula was compared on riders who train. The 109% rule comes from a study of trained cyclists, so treat your row as a starting point: the heel check and a knee bent 25 to 35 degrees at the bottom of the stroke set the final height.
17. The top speed is printed three ways. "22 Mph" on the spec strip, "Up to 24 MPH" in Smartravel's table, "(PAS Level 5)" in ZOONLAI's; the Amazon listing for the L24 lists assist modes at "20 mph / 28 mph / 35 mph". This review follows the two stores.
18. The frame material and the tire width differ by document. Neither store prints a frame material, and the Amazon listing gives "High Carbon Steel"; the stores print "24"x2.0"" and "24X2", the listing "24×1.95". Whether the pack lifts out for charging is not described on either store's page; ask us and we will get Smartravel's answer in writing.
19. The group's documents state more than one warranty term: a "1 Year Warranty" badge, "a 12-month limited warranty" in Smartravel's FAQ, "a 2-year warranty for each ebike" in its help block, and 12 months on ZOONLAI's warranty page. This review states 12 months, as our listing does.
20. Owners' words are theirs. Speeds, build times and impressions were taken on their own units and ground; the price and stock were read on September 28, 2026 and can change, and the recall search covers the CPSC's US database under the names listed.

The bottom line

For $339.99, the UrbanX puts a 500 W rated hub motor and a 504 Wh pack on a light 24-inch frame, with a suspension fork, disc brakes at both ends, a headlight, a color display and a Shimano 7-speed.

Count on about 34 level miles at 15 mph on the throttle for a 180 lb rider, and about 58 with light pedaling. Every 1,000 feet of 4 to 8% climbing at 10 mph costs another 149 to 195 Wh on the throttle, and keeping a quarter of the pack back covers stop-and-go days.

It suits riders who want an affordable, light commuter for flat and rolling streets and paths, within the group's rider windows, who will pedal on the steep parts. Paid through Shop Pay, the $339.99 becomes 4 interest-free payments of $84.99. Our Smartravel brand profile sets the UrbanX beside the five other Smartravels we sell.

Settle the class before the street: the 500 W rating sits under the 750 W line, and the speed at which the assist stops decides the rest. Tell us your state and your commute, and we will get the cut-off from Smartravel and lay out what the rules there ask of the UrbanX.

Source register

Each document this review relies on, and what it supports.

T1 is the record itself, read from the party that issued it: a statute, a federal regulation or notice, the maker group's own product pages, records and policies, and our own store record.

T2 is a party's own publication about its product or its measurements: the motor makers' and cell makers' published figures, the research groups' and laboratories' measurements, a marketplace listing under the brand's name, and owners' recorded words.

Expiry conditions

Re-read this page if Smartravel changes the UrbanX's price, pack, motor rating, speeds, range figures, weight, payload or rider windows on its US page; if ZOONLAI changes its page, its dimension image or its UrbanX parts; if Smartravel confirms in writing the assist cut-off, the seat-post range, the pack's removal or the warranty for the unit shipped; or if the price or the Shop Pay terms change on our store.

Re-read it as well if a recall is published naming Smartravel, ZOONLAI or the UrbanX, or if any statute quoted here is amended. Verified September 28, 2026.

References

The full bibliographic record for each document cited above, with the date it was retrieved.

1. Smartravel, ZOONLAI UrbanX — product page (spec strip, feature copy, Spec&Size, FAQs, customer reviews, trust badges, dimension image, as rendered under the US market). Retrieved September 28, 2026. https://www.smartravelor.com/products/zoonlai-urbanx
2. Smartravel, ZOONLAI UrbanX — product record, price and compare-at price by variant, SKU L24D. Retrieved September 28, 2026. https://www.smartravelor.com/products/zoonlai-urbanx.json
3. ZOONLAI, ZOONLAI UrbanX — product page (spec strip, Spec&Size, FAQs, dimension image, customer reviews, UL badge). Retrieved September 28, 2026. https://www.zoonlai.com/products/zoonlai-urbanx
4. ZOONLAI, Home page, the brand paragraph: "Zoonlai and Smartravel are part of the same company, operating two dedicated product lines to serve different riding needs". Retrieved September 26, 2026. https://www.zoonlai.com/
5. ZOONLAI, Warranty & Return Policy (the component table, the battery's cycle rating and the dealer route). Retrieved September 28, 2026. https://www.zoonlai.com/pages/warranty-return-policy
6. ZOONLAI, ZOONLAI UrbanX L24 Battery, product listing ($199.00, orderable), with the UrbanX tire, display, headlight and brake-pad listings. Retrieved September 28, 2026. https://www.zoonlai.com/products/zoonlai-urbanx-l24-battery
7. ZOONLAI (brand), 24” Electric Mountain Bike For Adults,500W Motor 48V/10.5Ah LIB City Ebike — Amazon listing (model L24; the motor, assist modes, frame material and tire width). Retrieved September 28, 2026. https://www.amazon.com/Electric-Mountain-Adults-Motor-10-5Ah/dp/B0H2DGCW25
8. ZOONLAI, ZOONLAI UrbanX Installation Video, YouTube, July 12, 2026. Retrieved September 28, 2026. https://www.youtube.com/watch?v=tBJXYdPTMNw
9. United States Patent and Trademark Office, ZOONLAI, Registration No. 7,682,289 (Serial No. 98204833), status record. Retrieved September 26, 2026. https://tsdr.uspto.gov/statusview/sn98204833
10. United States Patent and Trademark Office, SMARTRAVEL, Registration No. 7,533,630 (Serial No. 98201852), status record. Retrieved September 26, 2026. https://tsdr.uspto.gov/statusview/sn98201852
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15. Bureau of Land Management, 43 CFR part 8340, § 8340.0-5, paragraphs (a)(5) and (j) (85 FR 69223, Nov. 2, 2020). Retrieved September 26, 2026. https://www.ecfr.gov/current/title-43/subtitle-B/chapter-II/subchapter-H/part-8340
16. Forest Service, US Department of Agriculture, 36 CFR § 261.13 — Motor vehicle use. Retrieved September 26, 2026. https://www.ecfr.gov/current/title-36/chapter-II/subchapter-B/part-261/subpart-A/section-261.13
17. Forest Service, US Department of Agriculture, 36 CFR § 261.1b — Penalty (89 FR 92815, Nov. 25, 2024). Retrieved September 26, 2026. https://www.ecfr.gov/current/title-36/chapter-II/subchapter-B/part-261/subpart-A/section-261.1b
18. US Forest Service, Directive Publication Notice, 87 FR 41278 (July 12, 2022), recording the final e-bike directives issued March 31, 2022. Retrieved September 26, 2026. https://www.federalregister.gov/documents/2022/07/12/2022-14777/directive-publication-notice
19. US Consumer Product Safety Commission, Recall database, recall title, product name and manufacturer queries for Smartravel, Smart Travel, Smartravelor, ZOONLAI and ZonMen, a model-code read of a 623-record corpus, and controls Ancheer / Specialized / Trek. Retrieved September 28, 2026. https://www.saferproducts.gov/
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