assessment & quoting
To begin the process, please visit our “Get Started” page and fill out the form, including photos of the damaged area. Being honest about what happened to your bike is essential as it will help us advise the next steps. It is common to damage your bike in large crashes or localised incidents. If insurance is involved or the damage is significant, we will need to fully assess the frame and fork to provide the necessary answers and documents. However, a spot-check inspection may be sufficient if the damage is limited to one area. The photos you provide will help us to determine the location, size, and type of damage, as well as the complexity of the paint and graphics work on your frame. Paintwork can range in price significantly.
We strive to give you as much information as possible before you bring in your frame for a physical assessment. Our specialist non-destructive testing (NDT) methods are best for understanding the damage and providing an accurate quote. Testing ensures that there are no surprises later on during the repair work, and you can make informed decisions upfront before we start repairing. We can often assist in sourcing replacement frames and components. There could also be a manufacturing defect, which may give you other options for restoring your bike. We often get told our fees and reports are worth every dollar, and we proudly offer this service to cyclists. NDT technicians are the unsung heroes that keep us safe – they keep planes in the sky and bridges and structures from falling. Early damage detection can save you money and keep you safe.
inspection services
STANDARD QUOTE INSPECTION
local area assessment - no report
FULL FRAME & FORK INSPECTION
assessment Report
FULL FRAME [NO FORK] INSPECTION
assessment report
WHEEL & RIM INSPECTION
local area assessment - no report
HANDLEBAR OR SEAT POST INSPECTION
assessment Report
FORK ONLY INSPECTION
assessment report
* Standard quote inspections are free if you go ahead with a repair, otherwise a $150 fee is chargeable to cover our time and use of specialised test equipment.
** Full component ultrasound scan may be limited by part design and geometry. Inspection requires parts to be stripped down, which can be done by us at an additional cost.
Non Destructive Testing (NDT) inspection techniques - Carbon Bike frames
ultrasonic testing (UT) Ultrasound Flaw Detection of carbon fibre composites - carbon bike frames
Carbon Bike Doctor uses a portable ultrasonic flaw detector instrument to non-destructive test (NDT) and scan to identify flaws in carbon fibre bike frames and components. Our flaw detector provides advanced conventional ultrasonic performance with analysis software and a range of transducer frequencies to detect flaws in carbon fibre laminates. Ultrasonic testing (UT) is the best method for testing carbon frames and components because it is highly accurate, provides instantaneous results, and is entirely non-destructive and safe. Carbon Bike Doctor has invested extensively in the right equipment and experience to bring this aerospace industry-accepted testing method to the bike industry.
Sound waves are vibrations that travel through a medium at a specific velocity and direction. Ultrasonic flaw detectors generate and display an ultrasonic waveform that a trained operator interprets to locate and categorise flaws in test pieces. The speed of sound waves varies depending on the medium's density and elastic properties, and all sound waves oscillate at a specific frequency. Ultrasonic flaw detection is a comparative technique that uses reference standards and generally accepted test procedures to identify specific echo patterns that correspond to the echo response from good parts and representative flaws.
electronic digital tap hammer and acoustic/ percussion testing for composite damage assessment
Coin or tap hammer testing is a non-destructive method used to examine laminated structures, but it has limitations. In colaboration with WichiTech Industries, Boeing Aerospace has developed an Electronic Digital Tap Hammer that supplements the operator's assessment with a numeric readout. This hammer is insensitive to the magnitude of the hammer hit but sensitive to the local stiffness of the composite structure. It eliminates the effects of background noise and operator differences on the inspection results. Carbon Bike Doctor uses this technology to provide quick, non-invasive, and quantitative results that can detect and confirm cracks, delamination and voids on parts of your carbon frame or component. We often use this method with ultrasound or to show customers the findings on their frame, as the results are easily interpreted.
Visual Inspection - NDT
Non-destructive testing always begins with a visual inspection carried out by an experienced technician. To begin the inspection, the technician will consider the details provided by the customer regarding the incident that led to the damage. They will then use a range of equipment, which may include high-intensity spot lamps, fibrescopes for internal inspection of tubes, magnifying loupes, penetrative solvents, and cotton gloved hands or cloths to sweep over the surface and feel for any fractured carbon fibre shards or anomalies.
tech talk: carbon fibre properties
what forces cause damage to carbon fiber?
The bike frame has been designed to be strong in the directions needed to take the loads under normal riding conditions. Carbon fibre can be designed to have directional strength or even flex if so desired. The frame would be much heavier if it was designed to have strength in all directions and be able to take loads outside of normal use. When a bike is crashed or crushed the frame is receiving forces that it was not designed to take.
Many of the latest model frames are designed to be as light as possible and have refined the manufacturing techniques so there is no excess material. Essentially durability has been sacrificed for lighter weight. Repair of damage and testing for damage is more important than ever.
As carbon fibre is made from many different layers an understanding of how the loads are received by the material and how it reacts to different loads is critical when assessing damage or bike frame.
Carbon fibre has the greatest strength in tension. Conversely, carbon fibre will fail in compression before there is a fail in tension. Often this can be on the inside of a tube and is the greatest contributor to ‘hidden damage’, i.e. no external signs of failure.
tensile loading
Under tension carbon fibre is very strong – tensile loads are carried by the long carbon fibres – like a rope.
Compressive Loading
Compressive loading of the carbon fibre the adhesive and stiffness properties of the resin system are crucial, as it is the role of the resin to maintain the fibres as straight columns and to prevent them from buckling. This why repairing the bike frame with the same Pre-preg / thermoset resin system is crucial as the resin is an important part of the material’s mechanical properties. Wet layup resins are not what the bike is made from so the bike should not be repaired in this method.
As loading carbon fibre in compression relies heavily on the resin and the resin is not as strong as the carbon fibre the material is more likely to fail in compression. When assessing a frame or damage it is important to understand the direction of the forces applied and how the material reacts. This is the reason we ask how your bike got damaged or what happened in the incident.
Shear Loading
The below image shows a composite experiencing a shear load. This load is trying to slide adjacent layers of fibres over each other. Under shear loads the resin plays the major role, transferring the stresses across the composite. For the composite to perform well under shear loads the resin element must not only exhibit good mechanical properties but must also have high adhesion to the reinforcement fibre. The interlaminar shear strength (ILSS) of a composite is often used to indicate this property in a multi-layer composite (‘laminate’).
Flexural Loading
Flexural loads are really a combination of tensile, compression and shear loads. When loaded as shown, the upper layers are put into compression, the lower layers into tension and the central portion of the laminate experiences shear loading.
When a carbon fibre tube or plate flexes there are shearing forces between the layers of carbon fibres. The resin plays an import role here. Pre-preg / thermoset resins = GOOD; wet resin layup = NOT AS GOOD.