Industry News
Devinci Chainsaw Recall Update Explained
As Devinci nears completion of replacing 100% of the frames affected by the recall they've released a statement explaining what led to several of their frames breaking and how they have gone about remedying the problem. I commend Devinci on their transparency and we are excited to see the re-launch of the Chainsaw soon.
PRESS RELEASE FROM DEVINCI BELOW:
As many of you know, our gravity platform, the Chainsaw, was impacted by a recall last August. We initiated this voluntary safety recall because we are deeply committed to our riders’ safety. While only a few incidents occurred, the severity of the potential issue was significant, and as a brand, we were unwilling to create any risk for our valued customers. When you purchase a bike from us, we want you to feel safe at all times and ride with complete confidence. To remain transparent with our community, here’s a look behind the scenes at what has been happening within our factory over the past few months as we prepared to re-launch the Chainsaw.
Following the recall, our team of engineers and technicians got to work immediately. The process was not taken lightly. They conducted rigorous tests on more than sixty frames to pinpoint the issue and replicate the failure in our lab. These tests and further examinations revealed that, in specific cases, the penetration of the headtube welds was not optimal to withstand the demands this platform was designed for. During our investigations, we also discovered that the arrangement of tube junctions could lead to welds with insufficient penetration, compromising the required strength levels under high load.
Our team was able to recreate the types of failures we experienced, which alerted us to initiate this recall. Recreating those failures is crucial in understanding the issue.
We’re now 100% confident that the new Chainsaw for 2025, along with all replacement front triangles made for the previously impacted production runs, are solid and ready to take on everything they were designed for. We adjusted the tube cut geometry at the junctions to ensure consistent root weld penetration across all frames during production. This modification allows for better control of the weld's effective throat length, a key factor in ensuring its strength. In short, the updated front triangle now features a larger and stronger weld at the junction of the toptube, downtube, and headtube. This enhancement makes the front end of the bike more resistant to significant impacts and stresses. How do we know this? Testing.
The updated Chainsaw front triangle above is shown in a Finite Element Analysis. By simulating forces and loads, we can use the colour variations to identify sections at risk of deformation or material cracking.
Extensive testing has been conducted in our laboratory, including high-strength fatigue tests, ultimate strength tests, and front impact tests with varying weights. In each of these exercises, the goal was to subject the frame to forces far beyond what a rider would typically apply, and to quantify its resistance. These tests are designed to prevent material cracks and ensure that the welds are strong, durable, and capable of withstanding these rigorous conditions.
On the left, an updated Small Chainsaw frame is set up on the test bench for what we call an ultimate strength test. On the right, the desired result: tubes buckling instead of separating or cracking.
Another version of an ultimate strength test. Once again, the desired outcome is downtube and toptube buckling rather than separation or cracking.
After the lab tests, the frames underwent real-world testing over several months. This ensures not only durability but also that the ride quality meets our high standards. Think of this as the final step in our approval process.
At Devinci, we take immense pride in our Canadian heritage, crafting high-quality aluminum bike frames since 1987. Our commitment has always been to build durable bikes that meet the needs of the most demanding riders. This recall may appear to be a misstep to some, but for us, it is an opportunity to stand behind our products, learn from our mistakes, shed more light on the Canadian bicycle manufacturing process, and continue to refine our local expertise.
Height - 6'/183cm (mostly legs)
Weight - 155lbs/70kg
Inseam - 34"/86cm
Ape Index - The Original Slinky™
Age - 23
Bar Width - 780mm
Preferred Reach - 485-500mm
Comments
Bikes
3 weeks, 6 days ago
That is a nice transparent response.
Questions:
Was the testing originally performed not adequate or the frames weld quality was higher than the range of quality for the production runs.
How do you prevent similar future instances to flag a design that is susceptible to normal fabrication quality issues (assuming this wasn’t a gross quality issue)
Again, the transparency is really welcome
Reply
Mammal
3 weeks, 6 days ago
I doubt this will get directly through for a response, but based on the info they provided, my guess on the first question:
The original testing sample size was smaller and didn't catch the issue, and/or the field failures allowed them to key in on certain frame sizes that were more prone to failure due to the differences in cut/miter/join location ("arrangement of tube junctions could lead to welds with insufficient penetration").
Reply
Matt Cusanelli
3 weeks, 6 days ago
Hey! I’ve reached out to my contact at Devinci and they’ve forwarded your question to their engineering team. If they don’t respond on here in the next few days they’ll likely forward me a response that I’m happy to pass along to you. Thanks!
Reply
Matt Cusanelli
3 weeks, 5 days ago
Hey again. Devinci got back to me. Answers to your questions below!
Was the testing originally performed not adequate, or was the weld quality on the prototype higher than in production?
Devinci's answer:
The testing process was fully adequate, (and knowing what a couple other companies are doing, our processes are sometimes well above industry standards) and was successfully completed on early production samples. The issue was not with the testing, but rather with a rare welding inconsistency that occurred during production.
The affected frames came from the same department that built our test prototypes. However, during production, we later discovered that in a small number of cases, weld penetration was insufficient due to variability in how certain tube angles were being cut and assembled. These conditions made it harder to ensure consistent weld quality across all frames.
To be safe, and because we couldn't trace the issue to a specific batch, we made the decision to recall all potentially affected bikes. We tested nearly 60 frames to fully understand the issue. In response, we've adjusted tube cutting angles to better suit large-scale/mass production and ensure consistent weld integrity going forward.
How will you prevent similar issues in the future—specifically when a design might be susceptible to small variations in fabrication quality?
Our answer:
We've taken two major steps to prevent similar issues moving forward.
1. Improved Design Guidelines: We’ve established new internal design rules to optimize weld joints right from the start of the development process. This helps ensure that even with normal variations in fabrication, weld quality remains consistent and strong.
2 - Enhanced Welding Oversight: We've implemented stricter procedures during welding to closely monitor weld penetration at each stage. This gives us better quality control throughout the entire production process.
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ohio
3 weeks, 2 days ago
This is an amazing level of engagement and a fantastic response. Great work, Devinci.
Reply
Tehllama42
3 weeks, 5 days ago
TL;DR, not enough design margin on the weld pool depth so that small changes in how the jigs are setup can result in the weld being the weak spot. That's not an easy to inspect spot
The transparency here is a huge plus. Having 'helped' with destructive testing of Devinci carbon frames, the design margins are very healthy in most places.
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