Bicycle Frame Vertical Vibration Fatigue Test Machine (FH-S2989)

Dual-motor vertical fatigue testing for bicycle frames — ISO 4210-6 · JIS D9401 · GB 17761.

The FH-S2989 applies controlled vertical vibration loads to a fully-assembled bicycle frame at adjustable frequency (6–10Hz) and amplitude (0–25mm), replicating the cumulative road-impact stresses a frame experiences over its service life. Two independent DC drive motors deliver stable, resonance-free excitation across the full test range; a 6-digit programmable cycle counter and Omron/Schneider electrical controls make the machine straightforward to operate and reliable in high-cycle production QC environments.

Quick Specs

• Standards: ISO 4210-6, JIS D9401 5.0, GB 17761

• Test load: 85kg (or as specified)

• Frame/wheel size range: 500–1,200mm

• Vibration amplitude: 0–25mm

• Test frequency: 6–10Hz (adjustable, resonance-avoidance required)

• Drive: Dual DC motors (independent)

• Eccentric cam stroke: 25.4mm

• Control: Omron/Schneider components, 6-digit cycle counter

• Power: AC 380V, 15A

• Machine dimensions: 2200 × 700 × 1900mm (W×D×H)

• Machine weight: ~320kg

Table of Contents

1. Why Vertical Vibration Testing Matters for Bicycle Frames

2. Overview of the FH-S2989 Test Machine

3. Standards Covered: ISO 4210-6, JIS D9401, GB 17761

4. Test Method and Specimen Setup

5. Design Features of the FH-S2989

6. Technical Specifications

7. How the FH-S2989 Testing Process Works

8. Benefits for Frame Manufacturers and Testing Labs

9. Choosing the Right Bicycle Frame Vibration Tester

10. Real-World Application Scenarios

11. FAQs for the FH-S2989

12. Related Testing Equipment

13. Get a Quote from Feihong Machine

Why Vertical Vibration Testing Matters for Bicycle Frames {#section-1}

Every kilometer a bicycle travels transmits road-surface irregularities directly into the frame through the wheels and axles. Individual impacts are small — a pebble, a road joint, a shallow pothole — but at typical riding cadence they accumulate into millions of load cycles over a frame's service life. The failure mode this creates is not sudden overload fracture; it is fatigue crack initiation at stress concentrations — weld toes, tube intersections, dropout edges — that propagate slowly and invisibly until the structure fails without warning.

Vertical vibration fatigue testing accelerates this cumulative load history into a controlled laboratory test. A frame is loaded to represent rider and load mass, then subjected to a defined number of vertical oscillation cycles at a frequency and amplitude that reproduces road-impact stresses. The test does not replicate every nuance of real riding — it is not designed to. It is designed to reveal whether a frame geometry, tube specification, weld quality, or material selection contains a fatigue weakness before that weakness manifests in a field failure.

This is why ISO 4210-6, JIS D9401, and GB 17761 all require vertical frame vibration testing as a mandatory element of type approval and production QC — not as an optional additional verification, but as a baseline requirement for every frame design that claims conformance.

For manufacturers exporting to Japan (JIS), the EU (ISO 4210), or China (GB 17761), having in-house vertical vibration test capability is a prerequisite for self-certification or third-party certification preparation — and it is the difference between catching a fatigue problem at the development stage and catching it after a field incident.

Overview of the FH-S2989 Bicycle Frame Vibration Test Machine {/section-2}

The FH-S2989 is a dual-motor vertical vibration fatigue tester designed specifically for bicycle frame compliance testing under ISO 4210-6, JIS D9401 5.0, and GB 17761.

The machine mounts a complete bicycle frame in the test fixture — front and rear axles horizontal (or wheel contact points horizontal for mixed-diameter configurations), saddle tube at the assembly limit mark, and load applied via a saddle-form load seat with hanging rods and weights at the saddle position, plus loads fixed bilaterally at the bottom bracket and secured at the head tube. This load distribution matches the standard-specified weight placement for all three referenced standards.

Two independent DC motors drive eccentric cams that produce the vertical oscillation. The dual-motor architecture provides the driving force and mechanical balance needed for stable, resonance-free operation at the target test frequency — a single-motor design at this load and frame size can introduce lateral oscillation components that compromise result accuracy and machine longevity.

Test frequency is adjustable between 6 and 10Hz across a 0–25mm amplitude range, with the operator required to avoid resonance frequencies of the specific frame under test — as specified in the standard method. A programmable 6-digit cycle counter using Omron and Schneider electrical components controls the test duration and stops the machine automatically on completion or fault.

Standards Covered: ISO 4210-6, JIS D9401, GB 17761 {#section-3}

ISO 4210-6 — Bicycles: Safety Requirements for Frames and Forks

ISO 4210 is the primary international bicycle safety standard, with Part 6 specifically addressing frame and fork requirements. The vertical vibration test defined in ISO 4210-6 applies to all frame categories (city/trekking, mountain, racing, children's, and cargo), with test loads and cycle counts varying by category. The FH-S2989's 500–1,200mm wheel size range and 85kg test load capacity cover the adult frame categories specified in ISO 4210-6.

JIS D9401 — Bicycles: General Requirements (Japan)

JIS D9401 is the Japanese Industrial Standard for bicycles, widely used for type approval in Japan and by manufacturers supplying Japanese distributors or OEM buyers. Clause 5.0 covers frame and fork vibration endurance requirements using a test method closely aligned with ISO 4210-6 — same load application geometry, same horizontal-axle mounting requirement, same pass/fail criteria (no fracture, no significant deformation, no loosening after the specified cycle count).

GB 17761 — Safety Requirements for Electric Bicycles (China)

GB 17761 is China's mandatory national standard covering electric bicycles, which includes frame structural requirements aligned with the ISO methodology. Under the 2024 revision (effective December 2025), frame structural requirements remain enforced under the existing test framework. The FH-S2989's compliance with GB 17761 makes it directly applicable to QC programs for electric bicycle frames produced for the Chinese domestic market and for CCC certification preparation.

Test Conditions by Frame Category (JIS D9401 / ISO 4210-6 Aligned)

The load distribution and cycle count vary by frame category. The table below reflects the standard test conditions the FH-S2989 is designed to execute:

Reading the table: Load is distributed across three points on the frame — head tube, saddle seat, and bottom bracket — matching the geometry of Figure 1 in the standard. The excitation point is at the front axle midpoint via the vibration table; the rear axle is fixed. Total test load ranges from 45kg (toddler frames) to 75kg (adult diamond frames); required cycle count ranges from 40,000 to 100,000 cycles depending on frame category.

Standard Coverage Comparison

Test Method and Specimen Setup {#section-4}

The FH-S2989 implements the standard test method as follows:

Frame Mounting

The bicycle frame is mounted in the test fixture with front and rear wheel axles horizontal. If the frame is designed for wheels of different diameters (front ≠ rear), the wheel contact points — not the axle centerlines — are brought to the same horizontal level. This mounting geometry is specified in ISO 4210-6 and JIS D9401 to ensure load application angles are consistent across different frame geometries.

For frames with a seat tube installed, the seat tube is fixed at the assembly limit mark — the maximum insertion depth indicator — as specified in the standard. Testing with the seat tube at an arbitrary insertion depth would alter the load arm length and produce non-comparable results.

Load Application (Three-Point per Standard Figure 1)

Load is applied simultaneously at three anatomically-meaningful points on the frame, matching the geometry specified in the standard test diagram:

Head tube — 5kg across all frame categories: A fixed load secured at the head tube represents handlebar and front-end weight. This value is constant at 5kg regardless of frame category.

Saddle seat — 30–50kg depending on frame category: A saddle-form load seat is fitted to the seat tube at the assembly limit mark. Left and right hanging rods suspend circular weights from the seat. This is the largest load component — 50kg for adult diamond frames, scaling down to 30kg for toddler frames — representing rider body weight through the seat.

Bottom bracket — 10–20kg depending on frame category: Loads are fixed bilaterally at the bottom bracket shell, representing pedaling forces and leg weight. This is 20kg for adult diamond frames, 10kg for children's and toddler frames.

The excitation point — where the vibration table drives the frame — is at the front axle midpoint, as shown in Figure 1. The rear axle is fixed to the test bench. This geometry means the vibration table applies upward and downward displacement at the front axle while the rear is held, replicating the road-impact load path through the frame as it would occur in actual riding over rough surfaces.

Test Execution

With the frame loaded and fixture secured, the machine applies vertical oscillation at a frequency selected between 6 and 10Hz. The frequency is set by the operator and must avoid the resonance frequency of the specific frame-fixture assembly — a requirement common to all three referenced standards, because testing at resonance would amplify loads beyond the specified level and invalidate results.

The test runs for the number of cycles set on the 6-digit counter (cycle counts are defined per standard and frame category). Pass criteria across all three standards: no fracture, no significant deformation, and no loosening at any frame joint or fitting after the full cycle count.

Design Features of the FH-S2989 {#section-5}

Dual-Motor Drive

Two independent DC motors drive the eccentric cam system — one per excitation point — providing the balanced, symmetrical vertical force input that stable high-cycle frame testing requires. A single-motor design of equivalent output tends to introduce lateral force components that stress the fixture and frame in non-standard directions; dual-motor architecture keeps the loading axis vertical throughout the test.

Adjustable Eccentric Cam (25.4mm stroke)

The eccentric cam delivers a fixed 25.4mm mechanical stroke. Effective vibration amplitude is adjusted within the 0–25mm range by the setup — giving operators the flexibility to match the amplitude specified by the applicable standard or the frame manufacturer's test requirement.

Wide Frame Size Compatibility (500–1,200mm)

The fixture accommodates wheel sizes from 500mm to 1,200mm — covering children's bicycles (20-inch), compact adult folding frames (24-inch), standard adult city and mountain bike frames (26–29 inch), and larger cargo bike configurations. No fixture change is required across this range; adjustment is made within the test fixture.

Omron / Schneider Electrical Controls

Electrical components — contactors, relays, counters — use Omron and Schneider branded parts throughout. These are tier-one industrial automation brands with established spare-parts availability worldwide, reducing maintenance risk and downtime on a machine designed for multi-million-cycle endurance runs.

6-Digit Programmable Cycle Counter

The counter is settable to any value within a 6-digit range (up to 999,999 cycles), covering both the standard-specified fatigue cycle counts and extended endurance runs. The machine stops automatically on counter completion — no operator monitoring required during the run.

Safety and Operational Features

• Emergency stop provision on the working surface

• Automatic stop on cycle count completion

• Resonance-avoidance requirement managed by operator frequency selection (6–10Hz range allows the operator to step around the frame's natural frequency)

Technical Specifications of the FH-S2989 {#section-6}

Why These Specifications Matter

• 6–10Hz frequency range covers the test frequency bands specified in ISO 4210-6 and JIS D9401 while providing enough range to step around the resonance frequency of any frame in the 500–1,200mm size range — a practical necessity, since different frame materials and geometries have different natural frequencies within this band.

• 25.4mm eccentric cam stroke is the displacement value referenced in ISO 4210-6 for standard adult frame vertical vibration testing — the machine's fixed cam stroke directly matches the standard requirement without requiring an adjustment conversion.

• Load range 45–75kg covers all four frame categories: Adult diamond frames require a total 75kg load (head tube 5kg + saddle 50kg + bottom bracket 20kg) at 2G acceleration for 100,000 cycles. Non-diamond adult frames: 65kg at 1.8G for 70,000 cycles. Children's frames: 55kg at 1.6G for 40,000 cycles. Toddler frames: 45kg at 1.6G for 40,000 cycles. The FH-S2989's load system accommodates all four configurations without mechanical modification.

• Excitation acceleration 15.7–19.6 m/s² (1.6G–2G): The dual-motor drive is sized to sustain these acceleration levels throughout the full cycle count — 100,000 cycles at 2G for adult diamond frames takes approximately 2.8–4.2 hours at 8Hz, and the machine must maintain consistent excitation throughout without thermal derating.

• Omron/Schneider controls are a deliberate choice over lower-cost alternatives: on a machine running 40,000–100,000 cycles per certification test, component failure mid-run invalidates the test entirely and requires a full restart — making tier-one electrical components a straightforward cost decision.

How the FH-S2989 Testing Process Works {#section-7}

Step 1: Frame Mounting and Axle Alignment

The frame is placed in the fixture and aligned so that front and rear axles (or wheel contact points, for mixed-diameter frames) are horizontal. This is verified before loading begins.

Step 2: Seat Tube Positioning

If the frame includes a seat tube, it is inserted and secured at the assembly limit mark — the maximum insertion depth as marked on the tube.

Step 3: Load Application

The saddle-form load seat is fitted. Hanging rods and circular weights are attached to reach the required test load (85kg or specified). Bottom bracket side loads are fixed bilaterally; head tube load is secured with the fastening nut.

Step 4: Frequency Selection

The operator selects a test frequency between 6 and 10Hz, avoiding the resonance frequency of the loaded frame-fixture assembly. The cycle counter is set to the required number of cycles per the applicable standard.

Step 5: Test Run

The dual-motor drive is started. The machine runs the full specified cycle count automatically. No operator intervention is required during the run.

Step 6: Pass/Fail Inspection

On counter completion, the machine stops. The frame is inspected visually and by hand for fracture, significant deformation, and loosening at all joints, fittings, and load application points. Results are recorded against the standard's pass/fail criteria.

Benefits for Frame Manufacturers and Testing Labs {#section-8}

In-House Certification Readiness

Manufacturers with an FH-S2989 can run ISO 4210-6, JIS D9401, and GB 17761 vertical vibration tests before submitting frames to a third-party certification body — identifying failures at the development stage rather than at certification, where a failure requires design revision, remanufacture, and a re-submission cycle.

Production QC at Scale

Multi-Market Standard Coverage

The FH-S2989's simultaneous coverage of ISO 4210-6 (EU/international), JIS D9401 (Japan), and GB 17761 (China) means manufacturers targeting multiple export markets run the same test on the same machine — not separate tests on separate machines for each market's standard.

Cost Efficiency on Long-Cycle Tests

Standard cycle counts range from 40,000 cycles (children's / toddler frames) to 100,000 cycles (adult diamond frames). At 8Hz, 100,000 cycles takes approximately 3.5 hours; 40,000 cycles takes approximately 1.4 hours — all unattended. The FH-S2989's auto-stop on counter completion means these runs occupy machine time without occupying operator time. A factory running two shifts can complete multiple frame certifications per day with a single operator loading and unloading between runs.

Choosing the Right Bicycle Frame Vertical Vibration Tester {#section-9}

When evaluating bicycle frame vibration test machines, the following points help differentiate genuinely compliant equipment from lower-specification alternatives:

Single-Motor vs. Dual-Motor Drive

A single DC motor driving a single eccentric cam can produce vertical oscillation, but at the load levels and frequencies required for frame fatigue testing, a single eccentric introduces lateral and rotational force components alongside the intended vertical component. The dual-motor architecture in the FH-S2989 drives balanced excitation — keeping the test loading axis vertical and the results consistent with the standard intent.

Frequency Range and Resonance Management

The 6–10Hz operating range is not arbitrary — it brackets the typical first vertical resonance frequencies of loaded bicycle frames in the standard size range. A machine with a narrower frequency range may not allow the operator to step around a specific frame's resonance; a machine with fixed frequency provides no adjustment at all. Confirm the tester offers the full 6–10Hz range with fine enough adjustment to avoid resonance.

Counter Resolution and Auto-Stop

For tests requiring 100,000+ cycles, a 5-digit counter is insufficient (maximum 99,999). The FH-S2989's 6-digit counter handles any standard-specified cycle count with headroom for extended endurance programs.

Electrical Component Brand

Industrial-grade electrical components (Omron, Schneider) versus generic alternatives matter on a machine used for certification testing: component failure mid-run invalidates the test and requires a full restart. Verify the brand and grade of contactors, relays, and the cycle counter itself.

Real-World Application Scenarios {#section-10}

A mountain bike frame manufacturer used in-house ISO 4210-6 vertical vibration testing to evaluate three candidate weld bead profiles on a new rear dropout design — running the standard test cycle count on each variant and identifying one profile that developed a micro-crack at the toe before the required cycle count, allowing the welding parameter to be corrected before tooling was committed.

An OEM producing bicycle frames for Japanese distribution used JIS D9401 5.0 vertical vibration test data — generated on the factory floor before shipping — to satisfy the importer's incoming QC requirement, replacing a previously slow third-party lab test cycle with a faster in-house validation that cut the pre-shipment lead time by approximately two weeks per production batch.

An e-bike frame manufacturer producing for the Chinese domestic market runs GB 17761 frame vibration tests as part of its final QC sequence before CCC submission, catching a batch of frames with inconsistent seat tube bonding before they entered the certification test pool — avoiding a failed certification run and a six-week delay.

FAQs for the FH-S2989 Frame Vibration Test Machine {#section-11}

What standards does the FH-S2989 comply with?

ISO 4210-6 (international bicycle frame safety), JIS D9401 5.0 (Japan), and GB 17761 (China electric bicycle standard). The test method and load geometry match all three standards' vertical vibration test requirements.

Why does the machine have two motors?

Dual DC motors provide balanced vertical excitation force without the lateral oscillation components that a single eccentric motor introduces at these load levels. This keeps the test load axis strictly vertical — consistent with the standard method — and reduces uneven mechanical wear on the machine structure over long-cycle runs.

What does "avoid resonance frequency" mean in practice?

Every loaded frame-fixture assembly has a natural frequency at which it amplifies input oscillation (resonance). Testing at resonance applies higher-than-specified loads to the frame and invalidates results. The operator adjusts the machine frequency within the 6–10Hz range until a setting is found where the frame does not exhibit resonance behavior — typically identified by the absence of amplitude magnification. The wide frequency range of the FH-S2989 provides sufficient adjustment room to achieve this for any frame in the 500–1,200mm size range.

What is the eccentric cam stroke, and can it be adjusted?

The eccentric cam has a fixed 25.4mm mechanical stroke — matching the displacement value in ISO 4210-6. Effective vibration amplitude is adjustable within the 0–25mm range through the test setup. The fixed cam stroke eliminates the need for cam replacement when switching between standard test configurations.

What frame sizes does it accommodate?

Wheel sizes from 500mm to 1,200mm — covering 20-inch children's frames, 24–29 inch standard adult frames (city, mountain, trekking, racing), and larger e-bike or cargo configurations. No fixture change is needed within this range.

How is the test load configured?

An 85kg load is distributed across three points: the saddle position (via load seat, hanging rods, and circular weights), the bottom bracket (bilateral), and the head tube (fastening nut). Total load at the saddle position equals the 85kg test requirement; bottom bracket and head tube loads are specified per the applicable standard clause.

Can it test non-standard load requirements?

Yes. The standard 85kg load is the default; customer-specified loads for non-standard frame categories (cargo, adaptive, tandem) are accommodated by adjusting the weights applied to the load seat and hanging rods.

What happens when the cycle count is reached?

The machine stops automatically. The operator then inspects the frame for fracture, deformation, or loosening per the pass/fail criteria of the applicable standard.

Related Testing Equipment {#section-12}

• Bicycle Frame Dynamic Road Load Fatigue Testing Machine — simulates pedaling and road-load forces on the frame in the horizontal plane; typically run alongside vertical vibration testing for complete ISO 4210-6 frame compliance

• Bicycle Fork Impact Test Machine — drop-weight impact testing for front forks per ISO 4210-6 and EN 14764

• Bicycle Handlebar and Stem Fatigue Tester — fatigue and load testing for handlebar assemblies per ISO 4210

• Electric Bicycle Comprehensive Test Machine (FH-ZD2988) — max speed, braking, and range testing for complete e-bike performance and GB 17761 compliance

Get a Quote from Feihong Machine {#section-13}

Feihong Machine (Dongguan Feihong Instrument and Equipment Co., Ltd.) designs and manufactures bicycle and electric two-wheeler testing equipment for frame manufacturers, component suppliers, and testing laboratories worldwide.

To get started:

• Request a Quote — share your frame size range, target standard, and production volume

• Schedule a Demo — see the FH-S2989 run a live ISO 4210-6 test cycle

Request a Quote →