In reply to quirky:
> (In reply to mike kann) cheaply made badly butted or welded steel frames will also fail catastrophically! carbon will take the minor knocks as it will flex and reform unlike steel or alu. a cheap badly made frame is a cheap badly made frame whatever it is made from!!
That's a fair enough point, though for a steel frame to suddenly fail there'd have to be something very wrong, and possibly something which could be picked up in quality control.
For a frame costing 300+ when bought new, especially from a company who wants to look after it's reputation, i'd say it's probably fairly unlikely to have a steel frame suddenly fail.
In my experience steel and alloy frames have failed at the lug or tube joins, and happened slowly over time.
One of these was a Falcon who I've since learnt had a poor reputation for the quality of their frames, it failed at the driveside chainstay-lug join, and was rusty there now I think about it, and another was a Dawes frame which had been bent in a side on crash from a BT van, and several years later started to fail at where the top tube joined the lug at the upper headtube. As a family none of use noticed it was bent slightly, oops.
The alloy frame was at the join where the little bit of tube for the seatpost to go into at the top of my Kona MTB gradually cracked, i'm guessing in part because I was too big for the frame, and sat on the back of the saddle all the time.
If you're spending a few hundred on a new steel frame, I don't think it's likely to suddenly break on you if you're doing what it's designed for, might be worth cleaning and checking it closely regularly anyway, as that gives peace of mind with spotting the start of any cracks early on, but apart from that i'd be chilled. (
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