Professional suspension fault diagnosis
Suspension Fault Diagnosis & Repairs
Professional diagnosis and repair for mountain bike suspension with unclear, intermittent or complex performance problems.
Find the Cause Before Replacing Parts
Suspension faults are not always caused by the first component that appears damaged. Air loss, oil leakage, unusual noises, inconsistent damping and reduced travel can have several possible causes.
CJSuspension carries out a structured inspection and diagnostic process to identify the source of the problem before recommending servicing, repair or replacement parts.
This service is suitable when the suspension has a fault that cannot be accurately diagnosed from its external symptoms alone.
Professional workshop assessment
What Is Included
- Review of the reported fault and suspension history
- External inspection for visible damage, leakage and contamination
- Air-pressure, spring and adjustment checks
- Inspection of mounting hardware and external interfaces
- Function testing through the available travel
- Assessment of rebound and compression adjustment operation
- Controlled disassembly where required to locate the fault
- Inspection of internal seals, shafts, pistons and damping components
- Identification of required service work and replacement parts
- Repair recommendation before significant additional work proceeds
Problems we investigate
Common Suspension Faults
- Fork or rear shock repeatedly losing air pressure
- Suspension stuck down or not returning to full travel
- Rebound or compression adjusters no longer working correctly
- Loss of damping or uncontrolled movement
- Oil leakage from seals, adjusters or internal interfaces
- Knocking, clicking, squelching or unusual internal noises
- Suspension that feels harsh despite correct pressure and setup
- Travel reducing or changing during use
- Rear shock remaining locked or failing to enter firm mode
- Performance changing significantly as the suspension heats up
- Repeated seal failure after servicing
- Intermittent faults that are difficult to reproduce
Check the complete system
The Suspension May Not Be the Only Cause
Some symptoms that feel like a fork or rear-shock fault can be caused by other parts of the bike.
Headset movement, loose mounting hardware, worn shock bushings, frame bearings, brake-pad movement, hub play, incorrect axle installation and cable contact can create noises or unwanted movement.
Incorrect spring rate, air pressure, volume spacing or damping settings can also create poor performance without an internal mechanical failure.
Supplying the complete bike may help when the fault cannot be reproduced with the suspension unit by itself.
Help us reproduce the fault
Information to Include When Booking
- Suspension brand, model, year and size
- Bike brand, model, year and travel
- A clear description of the problem
- When the problem first appeared
- Whether the fault is constant or intermittent
- The conditions that cause the fault
- Any recent crash, impact or transport damage
- Previous servicing or repair work
- Any replacement parts already installed
- Current air pressure, spring rate and adjustment settings where known
- Photos or video showing the fault where useful
Step-by-step assessment
How the Diagnostic Process Works
The suspension is first checked externally and tested using the symptoms described in the booking information.
Basic causes such as incorrect pressure, adjustment settings, loose hardware or installation problems are checked before the suspension is opened.
If the fault cannot be confirmed externally, controlled disassembly may be required. Internal components are inspected for damaged seals, contamination, fluid loss, wear, incorrect assembly or failed parts.
Once the likely cause has been identified, the workshop can recommend the appropriate service, repair or component replacement.
Faults that come and go
Intermittent Problems Can Take Longer to Diagnose
Some suspension faults only appear after repeated impacts, temperature changes, long descents or extended riding.
A component may operate normally during a short workshop check but fail once the suspension heats up or reaches a particular point in its travel.
Clear information, photos and video can help reproduce these problems. Additional testing or repeated inspection may be required when the fault is not immediately present.
Repair options
Repairs That May Be Recommended
- 50-hour lower-leg or air-sleeve service
- Complete 100-hour internal service
- Damper rebuild and bleed
- Air-spring service or component replacement
- Seal-head, piston or adjuster replacement
- Fork lower-leg bushing replacement and sizing
- Stanchion scratch repair or upper-tube replacement
- Steerer tube or upper-assembly replacement
- Shock mounting-hardware replacement
- Replacement of damaged shafts, bodies or internal hard parts
- Spring-rate, air-pressure or damping setup correction
- Replacement of an unsupported or uneconomical suspension unit
Approval before major work
You Will Be Contacted Before Significant Repairs
The initial assessment may identify additional servicing or replacement components that cannot be confirmed from the external symptoms.
The workshop will contact you before completing significant additional work or installing higher-cost components.
Minor items required to complete an already approved service may be handled within the agreed scope, while larger repairs will be discussed before proceeding.
Repair value and parts support
Some Suspension May Not Be Economical to Repair
Older, heavily damaged or unsupported suspension can require parts that are no longer available or cost more than the practical value of the repair.
Severe damage to a damper body, shaft, crown assembly, upper tubes or multiple internal components may make replacement the more appropriate option.
If a repair is unlikely to provide reasonable value or reliability, the workshop will explain the available options before further work is completed.
Workshop compatibility
Suspension Brands We Assess
CJSuspension assesses and repairs a wide range of mountain bike suspension forks, rear shocks and compatible dropper posts from recognised suspension manufacturers.
Repair options depend on the product design, technical information, tooling and replacement-parts availability.
Contact the workshop before booking if the suspension is uncommon, heavily modified, from an older production year or no longer supported by the manufacturer.
Queenstown or nationwide
Drop Off or Send by Courier
You can deliver the suspension directly to the CJSuspension Queenstown workshop or send it from anywhere in New Zealand.
Clean off heavy dirt and package the suspension securely. Protect all sliding surfaces, shafts, adjusters, mounting points and external controls from impact.
Include any loose parts or hardware required to reproduce the fault. Do not disassemble or attempt additional repairs before sending the suspension unless instructed by the workshop.
Please complete the online booking form before sending the suspension.
Diagnosis and repair information
Frequently Asked Questions
Important information about assessment charges, repair approval, replacement parts and courier servicing.
Is there a charge if the suspension is inspected but not repaired?
A diagnostic or assessment charge may apply where workshop time or disassembly is required to identify the fault. Any applicable charge can be confirmed before the assessment proceeds.
Can you provide an exact repair price before seeing the suspension?
Not always. Similar symptoms can have different causes, and some faults cannot be confirmed until the suspension is opened and inspected. An initial estimate may be possible from the product details and fault description.
Do you need the complete bike?
The suspension unit can normally be assessed by itself. The complete bike may be useful when the problem could involve frame bearings, mounting hardware, the headset, brake components or bike setup.
Should I send photos or video of the fault?
Yes, where practical. Photos and video can be particularly useful for intermittent noises, travel problems, oil leakage and faults that only appear under specific conditions.
Should I disassemble the suspension before sending it?
No. Leave the suspension assembled unless the workshop asks for specific components. Disassembly can remove evidence of the fault, introduce contamination or cause additional damage.
Will I be contacted before expensive parts are installed?
Yes. The workshop will contact you before significant additional repairs or higher-cost replacement components are approved.
What happens if the fault cannot be reproduced?
The suspension will be checked using the information provided. Intermittent faults may require additional testing, and the workshop may request more information about the conditions that cause the problem.
Can I send suspension from outside Queenstown?
Yes. Suspension can be sent to the workshop by courier from anywhere in New Zealand. Complete the booking form first and package the components securely.
How long does diagnosis and repair take?
Turnaround depends on the fault, testing required and replacement-parts availability. Simple faults may be resolved quickly, while intermittent or complex problems can require additional workshop time.
Find the cause of the problem
Book a Suspension Fault Assessment
Book online, describe the fault clearly and drop the suspension at the Queenstown workshop or send it by courier.