Can you scan or X-ray your Carbon Bicycle frame for cracks and voids?

🔍 Can You Scan a Carbon Bicycle Frame for Cracks and Voids? The Truth Behind the Tools

At Carbon Bicycle Repairs (CBR), we’re often asked: “Can you scan my entire frame to check for cracks or voids?” It’s a fair question—but the answer isn’t as simple as plugging in a machine and pressing “scan.” Let’s unpack the realities of carbon diagnostics and why a targeted, principled approach is not only smarter—it’s safer.

🛠️ In the Context of Carbon Frames

• X-rays: Can show density changes and major fractures, but struggle with layered composites like carbon fiber.

• CT scans: Offer more detail and can reveal internal anomalies—but they’re costly, require expert interpretation, and still may not clearly differentiate between paint cracks and fiber fractures unless resolution is extremely high.

So while a CT scan uses X-rays, it’s a more advanced, multi-angle process that builds a 3D image. Think of it like the difference between a photo and a full 3D model.

🧠 Why Full-Frame X-Rays Are a Diagnostic Illusion

1. Carbon Fiber Isn’t Homogeneous

• Unlike metals, carbon layups vary in fiber orientation, resin content, and wall thickness.

• This creates inconsistent X-ray contrast, making it hard to distinguish defects from normal structural variation.

2. X-Ray Imaging Is Not Plug-and-Play

• Industrial X-ray setups require precise calibration, shielding, and positioning.

• A full-frame scan would need multiple exposures from different angles—each one time-consuming and costly.

• Also an X-Ray image isn't going to show the BB area has ovalised

• Most CT scanners used outside of aerospace or medical labs don’t have the resolution needed to distinguish fine surface paint cracks from micro-fractures in carbon layups.

3. Targeted Scanning Is the Only Practical Approach

• You’d typically X-ray suspect zones—like impact sites and high stress areas such as, dropout junctions, shock mounts tupe junctions and pivot points, or BB shells—not the entire frame.

• Even then, interpretation requires a trained technician familiar with carbon composite behavior, not just radiographic technique.

4. Cost vs. Benefit Is Wildly Skewed

• A full-frame X-ray could cost more than the frame itself, especially if done properly.

• And unless paired with other diagnostics (e.g., ultrasound, thermography), it might still miss delamination or resin starvation.

5. False Confidence Is Dangerous

• Customers may assume an X-ray “clears” the frame, when in reality it might miss critical subsurface flaws.

• That’s why our principled boundary—repair only what can be confirmed—is not just ethical, it’s technically sound.

  
  

🔍 The CBR Diagnostic Process

Every inspection begins with context.

1. Incident Review

   We start by understanding what happened: crash details, symptoms, and rider feedback. This helps us identify stress, fracture zones and likely failure points.

   
   

2. Component Strip-Down

   The bike is fully stripped so we can inspect the frame without interference from hardware, cables, or components.

   
   

3. Thorough Visual Inspection

   We examine the frame under proper lighting, looking for signs of impact, stress, or fine cracking. Not all damage is obvious—especially when it’s internal. That is why a deep knowledge base is critical to accurate assessment.

   
   

4. Microscopic Imaging

   If we spot something suspicious that isn’t clearly an impact fracture, we capture high-resolution images to assess surface-level cracking or resin anomalies.

   
   

5. Endoscopic Imaging

   For internal tube damage, we use an endoscope to inspect the inside of the frame—especially useful in top tubes, seat tubes, down tubes, and BB shells.

   
   

6. Tap Testing

   We perform acoustic testing to detect delamination. A dull or inconsistent sound can indicate separation between layers.

   
   

7. Knowledge of mechanical resistance

   Knowing what is in normal range before a certain tube or surface area will deform under load, ie. 'soft spots', excessive flex.

   
   

8. Paint Removal (Last Resort)

   If uncertainty remains, we may carefully remove paint in the affected area to inspect the fibers directly. This is rare—microscopic imaging and the other diagnostics usually gives us the clarity we need.

Crack on rear of seat tube opening up under small amount of pressure applied.

🧠 Why Google Isn’t a Substitute for 6,000 Repairs

At CBR, we respect curiosity and we believe in educating our customers. But we also know that carbon diagnostics aren’t something you can master over a weekend of Googling or casual chats with friends—even if you or they are engineers.

Carbon fiber is not a textbook material. It’s layered, directional, and often deceptive. Diagnosing damage requires more than theory—it demands experience, intuition, and thousands of hours spent inside the workshop working with it.

🏁 About the Author: Why Experience Matters

James Perry, founder of Carbon Bicycle Repairs, brings more than just technical expertise to the workshop—he brings lived experience. As a former professional cyclist on both road and track, James has spent years pushing carbon fiber to its limits. Long before carbon became mainstream, he was moulding his own aero helmets and experimenting with layups, resins, and structural behavior.

That hands-on curiosity evolved into a deep understanding of how carbon responds to stress, impact, and fatigue—not just in theory, but in real-world riding and repair. Today, with over 6,000 frame repairs completed, James leads CBR with a rare blend of engineering insight, diagnostic precision, and rider intuition.