Alu frame. Two years ago I had to angle-grind the old headset off the old fork (fused together somehow) and caught the headtube by maybe 3mm. Since then have ridden it 4000+ miles 95% roads including 1200mi touring in France. Recently changed headset from cobbled-together-at-the-bike-coop to a nice new one and noticed a slight, very slight like fractions of a mm slight, bulge in the headtube around the cut region. Friend can’t feel it nor see it. I haven’t been able to ride the bike without stopping to check every few miles and have been constantly thinking about it and picturing a horribly graphic sudden failure because I can’t reassure myself the deformation has been there the whole time. I use this bike for everything and have a 2000mi tour booked in this year. Should I bite the bullet and buy a new frame or should I finally see someone about rumination/OCD/anxiety. Blacked out is LBS sticker.
by green-fen
5 Comments
I might ride it carefully but I definitely wouldn’t tour on it, better safe than sorry…
I don’t see much risk – that headtube doesn’t really bend – there’s a chance whatever you feel has always been there and you just noticed now changing the headset cups.
Only sign of weakness would be a crack imo – I don’t see the slightest trace of a crack building up and would not be worried at all if it was my bike.
The ends of the headtube are usually thicker, so given the usage if the damage was terminal it would have cracked by now. That part of the headtube will be under tension while breaking, which usually loads up gradually because riders don’t like face planting, or sudden events like hitting immovable objects, in which case the cut won’t cause the crash but might make the crash damage worse.
Paint the bare metal to prevent corrosion and monitor it for development of cracks.
It’s alloy. Any failure won’t be sudden, and you will see signs before it goes. Considering how far you have ridden without issue, I would say you are still working well within the loads the frame can take. Just keep an eye out for cracks and ride on!
In most applications, angle grinding ends up being a little more brute force than precision cutting. You likely put the bulge there when you caught the frame. If it’s held this long after, you’re likely fine to keep doing what you’ve been doing.