The aluminium steerer tube on my 2009 model Trek 7.6FX suddenly snapped with no forewarning, leading me to have a nasty accident. I'm curious if anyone has had a similar experience, or can help me understand how this could happen?
I used the bike for commuting short distances to/from work and for part of that journey I would have my three year old son on the back. I also commute with a backpack on and so all up am probably slightly heavier than the average cyclist, though still well within the design specs for the bike. The bike was always well maintained and only ever used for normal on road use. Strangely (fortunately!) the final breakage happened on a perfectly smooth concrete surface as I rode through the basement of my work building. I just mention this because it's odd that the fatigued steerer made it over all the bumpy London roads to work and then finally failed on a really smooth surface. That was very lucky for me, as had it happened on London city streets I'd likely have ended up under a bus, or with more serious injuries.
Trek took the bike back for inspection, but eventually denied responsibility, concluding I likely either had an earlier crash on the bike, or else was subjecting it to abuse - riding it down stairs was given as an example of abuse. None of that happened - the bike was only ever used for normal on road cycling. In contrast to Trek's findings the bike shop that did the initial inspection concluded that there were no signs of an earlier crash, abuse or anything of that sort. If Trek's claim that the bike had suffered an earlier incident involving the front wheel hitting an immovable object at speed, wouldn't the carbon forks have snapped or been damaged?
Trek did give me a new bike, but it's another FX model with the same carbon forks and alloy steerer. Since I know product abuse / an earlier crash were not features of the last one breaking I'm not sure how much confidence I can place in this new bike and whether I can safely put my son on the back. Basically I'm disappointed that a three year old safety critical component could fail like this. This bike has the exact same fork as fitted to many Trek road models and if there is a problem with it the recall would be significant. I also notice that when I bought my bike originally Trek used to advertise the FX models as being hybrids capable of some light offroad/trail use. They are now advertised as a cross between a road bike and a city bike, with no claims of any light offroad capability. I am cautious that Trek might have more awareness of a potential issue here than they've acknowledged to me. I expect the fork is fine for most light cyclists, but potentially a concern for heavier fast riders.
I'll post photos of the snapped steerer if there is interest.