The M-Series Multi-Speed Folding Bicycle serves transit fleet operators, municipal micro-mobility systems, and regional brand distributors requiring high structural durability under intensive daily use. Built on an optimized structural geometry layout, the platform pairs compact storage dimensions with rigid power transfer comparable to non-folding frames.
Production integrates automated robotic welding for frame load points and CNC-machined hinge interfaces to eliminate joint play over extended lifecycle deployment. Configuration options support derailleur-based cassettes or internal gear hubs, matching varied topography and fleet maintenance intervals.
Key Product Features
Dual-Safety Hinge Latches: Main frame and handlebar stem joints feature double-action mechanical latches backed by secondary spring-loaded safety pins to prevent unlatching during transit vibration.
CNC-Reamed Pivot Tolerances: Pivot housings are bored and reamed post-welding to house self-lubricating bronze bushings, maintaining alignment across 10,000+ folding cycles.
Internal Cable Routing: Shift and brake lines route internally through the top and down tubes, protecting lines from snagging during folding and reducing environmental exposure.
Integrated Braze-On Mounts: Rear stays and head tubes include structural threaded eyelets to accommodate commercial pannier racks, child seats, and front cargo blocks without clamp modifications.
Telescopic Seatpost Collar: Quick-release clamp featuring laser-etched height graduation markers enables rapid rider adjustment across shared-fleet deployments.
Technical Specifications
|
Parameter |
Specification |
|
Frame Material |
Hydroformed 6061-T6 Aluminum Alloy (Optional: 4130 Chromoly Steel) |
|
Wheel Size |
20 inches (ETRTO 406) |
|
Folded Dimensions |
82 cm x 34 cm x 68 cm |
|
Total Weight |
12.4 kg (Base configuration) |
|
Payload Capacity |
110 kg (Rider and gear combined) |
|
Recommended Rider Height |
145 cm - 190 cm |
|
Drivetrain Options |
Shimano Tourney 7-Speed / Shimano Nexus 3-Speed Internal Hub / Shimano Sora 9-Speed |
|
Brake System |
Mechanical Disc Brakes (160 mm rotors) or Forged Aluminum V-Brakes |
|
Crankset |
52T CNC-machined aluminum chainring with dual plastic guard, 170 mm forged arms |
|
Rim Specification |
Double-wall aluminum alloy, 36-hole, CNC-machined braking flanks |
|
Tire Specification |
20" x 1.75" with 3mm puncture-resistant Kevlar belt and reflective sidewall strip |
|
Safety Standard |
ISO 4210-2 (City and Trekking Bicycles) |
Frame & Structural Design
Frame architecture relies on a hydroformed main tube that routes torsional loads directly from the bottom bracket shell to the head tube gusset.
Hinge Node Engineering: The central folding block is forged from a single piece of aluminum to avoid internal casting voids. Contact faces undergo CNC milling to a flatness tolerance of 0.05 mm, preventing lateral flex during out-of-the-saddle acceleration.
Post-Weld Heat Treatment: Following robotic TIG welding, 6061 aluminum frames undergo T6 artificial aging cycles to restore structural yield strength at heat-affected zones (HAZ).
Surface Treatment Line: Frames pass through multi-stage chemical degreasing, micro-arc oxidation preparation, and electrostatic powder coating cured at 200°C to achieve salt-spray resistance.
Components & Configuration
Procurement teams select from standardized component tiers to align with target price points and maintenance cycles.
Cockpit Assembly:
Foldable alloy handlebar, ergonomic Kraton rubber grips, and sealed cartridge bearing threadless headset.
Saddle Integration:
Vacuum-formed polyurethane foam saddle over high-tensile steel rails, featuring an integrated underside grab handle for transit lifting.
Pedals:
Folding resin-body pedals with boron steel spindles (Upgrade option: Quick-release all-CNC alloy pedals).
Fastener Standards:
Grade 8.8 carbon steel and A2-70 stainless steel fasteners are utilized at all pivot points to resist galvanic corrosion.
Applications
Corporate Commuter Fleets: Deployed across industrial and tech campuses for employee inter-facility mobility.
Urban Micro-Mobility Networks: Integrated into station-based and dockless bicycle-sharing infrastructure requiring low-failure mechanical components.
Recreational Vehicle Storage: Utilized by RV and marine craft manufacturers as standardized onboard transit equipment.
Last-Mile Delivery: Fitted with front cargo racks for urban courier and food-delivery fleets operating in high-density zones.
Customization Options
OEM buyers adapt hardware specifications to brand guidelines without altering certified structural frame geometry.
Visual Branding: Headtube badge embossing, laser-etched frame serial numbers, and Pantone-matched powder coating.
Drivetrain Selection: Configuration matching local topography via single-speed, derailleur multi-speed (7S/8S/9S), or internal gear hubs (3S/5S/7S/8S).
Cockpit Layout: Straight flat bars or swept city handlebars; fixed or telescopic stem heights.
Accessory Bundling: Pre-installation of full coverage fenders, rear cargo racks, kickstands, and battery-powered LED lighting systems.
OEM & ODM Manufacturing
Production runs across two dedicated assembly lines with an annual output capacity of 180,000 units.
Tooling & Prototyping: In-house 3D CAD modeling, rapid CNC prototyping, and Finite Element Analysis (FEA) for frame modifications within 14 days.
Welding Cells: 12 robotic welding arms execute programmed weld paths to ensure penetration depth and eliminate manual operator variance.
Traceability System: Laser-etched QR codes on the bottom bracket shell link to raw material batch test certificates, welding operator IDs, and final QA logs.
Quality Control
Production lots undergo verification protocols aligned with ISO 9001 factory standards.
Hinge Fatigue Testing:
Pneumatic test rigs cycle folding mechanisms under a 100 kg vertical load for 50,000 continuous cycles to check joint wear.
Impact Verification:
Drop-weight tests and falling-mass impact tests per ISO 4210 guidelines verify fork and frame energy absorption.
Corrosion Exposure:
Component samples undergo 500-hour neutral salt spray exposure (ASTM B117) to verify fastener and coating integrity.
Dimensional Auditing:
Coordinate Measuring Machines (CMM) verify bottom bracket alignment, dropout parallelism, and headtube angles prior to painting.
Packaging & Shipping
Logistics configurations are optimized for standard container dimensions to reduce landed freight costs.
Export Cartons: 5-layer double-wall corrugated master cartons featuring internal EPE foam blocking and impact guards.
Container Loading Density:
Standard Knocked-Down (KD) Pack: 180 units per 20ft Container / 420 units per 40ft High Cube Container.
Semi-Assembled Pack (Front wheel and handlebar detached): 120 units per 20ft Container / 280 units per 40ft High Cube Container.
Moisture Protection: Anti-corrosion VCI (Volatile Corrosion Inhibitor) poly bags enclose each bicycle frame to prevent oxidation during ocean transit.
MOQ & Lead Time
Minimum Order Quantity (MOQ):
• Standard Specification: 100 units per color.
• Custom OEM (Frame color, custom decals, specific drivetrain): 300 units per order.
Sample Lead Time: 7 to 10 business days for stock configurations; 21 business days for custom-painted prototypes.
Production Lead Time: 30 to 45 days from deposit receipt and artwork sign-off, contingent on component availability.
FAQ
Q: How do the folding hinges prevent loosening after months of urban commuting?
A: The hinge uses an adjustable tension bolt paired with a spring-loaded locking lever. As normal mechanical wear occurs over time, the tension bolt can be tightened using a standard 4mm hex key to restore a rigid, play-free lock without replacing components.
Q: What international safety certifications accompany these folding bicycles?
A: All frame platforms are tested and certified to ISO 4210-2 standards by accredited third-party laboratories (SGS/TUV), covering structural fatigue, braking performance, and steering assembly strength. Test reports are supplied for import customs clearance.
Q: Can different drivetrain configurations be combined within a single MOQ order?
A: Yes. For orders meeting the 300-unit custom MOQ threshold, quantities can be split across different drivetrain variants (e.g., 150 units with 7-speed derailleur and 150 units with 3-speed internal gear hubs) provided frame paint and component tiers remain standardized.
Q: What is the protocol if a structural frame defect occurs during the warranty period?
A: A 5-year structural warranty applies to the main aluminum frame, alongside a 1-year warranty on mechanical components. Defective parts are processed via RMA protocol: photographic or video evidence accompanied by the laser-etched serial number is submitted, and replacement parts ship via express courier or within the next scheduled container.
Q: Are the bicycles shipped fully assembled, or is final dealer assembly required?
A: Units are shipped 85% pre-assembled in export cartons. Final dealer assembly requires installing the front wheel, tightening the handlebar stem, attaching the pedals, and adjusting the saddle height-taking approximately 15 to 20 minutes per unit with standard shop tools.
Q: How are custom brand logos applied to the frame?
A: Logos are applied using multi-layer water-slide vinyl decals applied beneath a protective clear powder-coat layer, or via direct laser etching on anodized surfaces, preventing peeling or scratching during fleet deployment.
Request a Quote
Submit project requirements to receive FOB/CIF pricing, technical drawings, or compliance test reports.
Required details for quotation: Target quantity, destination port, preferred drivetrain tier, and customization requirements. Inquiries receive a response within 24 business hours.
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