Modular Cargo Bike for Family Use
UM FLEX
One Bike. Every Version of Family Life.
Designed for Families
Customizable
EU Certified Safety
Modular Cargo Bike for Family Use
UM FLEX
One Bike. Every Version of Family Life.
Designed for Families
Customizable
EU Certified Safety
Modular Cargo Bike UM FLEX for Family Use
The UM FLEX is a modular long-john electric cargo bike designed for the way families actually live — carrying children one moment, groceries the next, and fitting into a hallway when the day is done. Front cabin swapped in seconds — pull to release, drop to lock. Built on a lightweight aluminum platform with cable steering, front suspension, and a low step-through frame, FLEX handles like a city bike and carries like a cargo bike. Compact enough to live with every day. Capable enough to replace the car.
Biomechanics & Comfort
Engineered for People, Not Just Performance.
Two decades of adult tricycle expertise, distilled into one thoughtfully engineered machine that keeps riders independent, active, and comfortable — for years to come.
From the universal joint in the steering column to the passivated disc rotors that resist corrosion in all weathers, every component reflects a deliberate engineering decision.
Compact Long-John UM FLEX
OEM-Ready Cargo Bike Platform
Built to support customization at scale — from frame design to component integration.

Adaptive Modular Frame
The FLEX is built on a modular aluminum platform engineered to switch between child passenger, cargo, pet, and camping configurations without changing the frame or purchasing separate accessories. Where most cargo bikes lock you into a single use case, the FLEX treats configuration as a feature — not a limitation.
Quick-Fold Front Cabin
One spring latch. Pull to release. Drop to lock.The FLEX's front cabin can be quickly folded up. With open, it switches between a child seat with 3-point harness and a cargo platform by stowing the seat. When folded, it transforms into a compact, convenient e-bike. Combined with the foldable stem, the FLEX achieves hallway-friendly storage dimensions. A fully capable family cargo bike that doesn’t require a garage.
Compact & Lightweight All-Aluminium Frame
At 2250mm long and constructed entirely from aluminium alloy, the FLEX is among the lightest and most compact long-john cargo bikes in its payload class. Light enough to lift over a kerb without assistance, short enough for standard bike parking, and easy enough to manoeuvre in tight urban spaces that full-size cargo bikes treat as obstacles.
Low Step-Through + One-Touch Kickstand
A minimal step-over height means mounting stays effortless in everyday clothes — no swinging, no balancing act. The one-touch kickstand deploys and retracts hands-free, holding the loaded bike stable during child loading and unloading without requiring the rider to bend down or use both hands. At full passenger weight, this is a daily safety requirement — not a convenience feature.
Cable Steering — Light Touch, Tight Turns
Cable steering — adopted by premium European cargo bike brands for its responsive, car-like feel — gives the FLEX a naturally light handling character that makes tight urban manoeuvres intuitive even when the front cabin is fully loaded. The result is a long-john that genuinely handles like a shorter bike — more agile in bike lanes, easier to park, and more confidence-inspiring for first-time cargo bike riders.
Height Adjustable Stem & Seatpost
A foldable stem with independent height and angle adjustment puts the handlebar exactly where it needs to be — for a shorter rider on the school run or a taller partner doing the weekend shop. The adjustable seatpost completes the fit below. For families sharing one bike across different body types, this level of adjustability removes the compromises that fixed-cockpit cargo bikes ask every rider to accept.
Boost Start Mode
At traffic lights with two children and a week of groceries on board, re-acceleration is where underpowered cargo bikes expose themselves. The FLEX's Boost Start Mode delivers immediate, controlled torque from a standing stop — eliminating the heavy-load hesitation that makes urban riding stressful and erodes rider confidence over time. Smooth from the first pedal stroke, every time.
Front + Rear Dual Load Zones
The FLEX runs a front cargo cabin and a MIK HD rear rack simultaneously — carrying children up front while managing rear cargo at the same time. School bags, groceries, a pet carrier, and two kids in a single run is not an edge case for FLEX users; it is Tuesday morning.
AirTag FindMy
AirTag FindMy integration keeps the FLEX locatable wherever the day takes it — parked outside school, locked at the supermarket, or left at the station. Security that works before the problem starts, without a subscription or dedicated hardware.
USE CASES
Designed for versatility, enabling seamless adaptation across multiple use cases and custom builds.
The UM FLEX is the right platform for brands and distributors sourcing cargo bike wholesale: urban families replacing short car journeys; female riders seeking a genuinely ergonomic and versatile cargo bike; lifestyle markets where modularity across family, pet, and leisure use justifies a premium; and retailers seeking a single SKU that covers multiple customer profiles without a fragmented catalogue.
Contact us for modular cargo bike wholesale pricing.




- Main Specifications
| Dimensions | 2250L × 700W × 1110H mm |
| Frame Material | 6061 Aluminum |
| Battery | 48V 15Ah,Samsung Battery Cells |
| Motor | Ananda Mid-Drive 48V/250W 120N·m / Hub Motor 48V/250W 55N·m |
| Gearing | Shimano 8-Speed Internal / 7-Speed External |
| Brakes | Hydraulic Disc Brakes, Front & Rear |
| Tyres | 20×2.125″, KENDA Tires with Puncture-Resistant Belt and Reflective Strips |
| Max GVW | 250 kg |
| Passengers | 1 Adult + 2 Children under 3 |
| Steering | Cable / Rod steering |
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At United Mobility, we put our customers first, delivering personalized solutions and exceptional support. From OEM/ODM customization to reliable warranty and responsive customer service, we are committed to ensuring your success with every step.
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We specialize in fully customizable e-bikes, cargo bikes to match your unique specifications. With dedicated design and R&D teams, we deliver innovative and high-quality solutions tailored to your market.
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We ensure long-lasting performance and reliability. No worry about the after-sale service. Our commitment to quality means every product is backed by strict testing and certification.
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Yes, we provide samples for market testing. Bulk orders are eligible for tiered discounts; Our Sales Team will offer you the detailed pricing.
Standard delivery time is 45-60 days , subject to order volume and production schedules. We provide shipping via sea, air, or express services depending on the demand, and support flexible trade terms like FOB, CIF, and DDP.
We offer customization for key components such as battery capacity, controller parameters, brake systems, paint colors, and more.(Click here for OEM/ODM service information)
Or simply share your requirements (e.g., design sketches or functional needs), and our team will provide a tailored solution.
Our products are certified with CE, TÜV, and E-MARK, meeting European and North American standards. The factory operates under the ISO9001:2008 quality management system with multiple inspections during production to guarantee high-quality products.
We offer a warranty of 2-8 years, covering core components such as motors and batteries. For after-sales support, contact us via our service email or hotline with your order number and a description of the issue. Our team will respond promptly.

