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Help - Is this a serious frame injury?(5 posts)

Help - Is this a serious frame injury?Helix
Jun 8, 2003 8:20 PM
I was cruising along at about 32-34km/hr yesterday when the permalink broke on my Campy chain without warning (not quite 5000 km on this chain). The chain proceeded to violently wrap itself around the derailler and the cluster, forcing the derailler into the rear stays of the frame. Obvious damage: Bent, mangled and shredded Record derailler, bent skewer, damaged teeth on the rear cluster, bent derailler hanger and small dent in the right seat stay near the dropout. Surprisingly to me, despite the force involved and the rest of the damage, none of the spokes broke, although the wheel (Campy Nucleon) is now slightly out of true.

The parts, although painfully expensive, can be replaced. My major question is the lugged steel frame (Colnago MLX). The derailler hanger is clearly out of alignment and the side of the dropout that is not attached to the frame stays appears to have bent slightly so that the dropout's gap is now wider than it normally is. Can the derailler hanger and dropout be bent back into position without seriously compromising the frame's strength? Or do I need to find a frame builder that can replace the dropout?

Any thoughts?

Thanks

Helix
From my knowledge you should be able to bend it backSprint-Nick
Jun 9, 2003 1:15 AM
This is just from my knowledge so you'll have to ask at the bike shop and see what they will be willing to do. Make sure you go to the most reputable one in the area for something like this.

Anyway to your problem, since it is a steel frame its repairable. Steel is a maleable metal that has a very long fatigue life under bending. I believe titatium is the same as well, but aluminum is not and should be replaced. With anything theres a risk though... bending aluminum its high, steel its low.

So when you take it to the shop they will use a special dropout tool designed specifically to bend fork and rear dropouts back into alignment. The bike shop should use this to realign your dropouts and get you back on the road. As for the chain I'd get them to check it for wear while you are in... especially if you have to replace your cassette.

Good luck getting your bike fixed.

Cheers,
Nick
Definately have a good frame builder look at itMel Erickson
Jun 9, 2003 5:35 AM
It could possibly be ok with just some bending but from your description it sounds moderately serious. Have a qualified frame builder take a look at it and do whatever repairs are necessary. It should definately be repairable and a builder is most qualified to either bend and repair or replace the mangled frame parts.
re: Help - Is this a serious frame injury?J2
Jun 9, 2003 6:50 AM
i've had a steel Serotta straightened out twice with no problems at all. but you have to find a shop that not only has the tools but knows how to use them, otherwise they could do more damage. but the right tools in the hands of the right person/shop can do amazing things, i thought my dropout was waaay to gone on one of the occasions, had a similar incident with a derailer literally exploding and remaining pcs wrapped around frame. but an hour after the shop owner had it it was good to go. i rode that frame for 5 more years after that. i still have the frame today hanging on the wall.
One more reason for lugged steel...Silverback
Jun 9, 2003 7:46 AM
Steel is remarkably tough--I once straightened a dropout that had been bent 90 degrees from the fork (bike fell off a cartop rack, and one side didn't release). I rode it for a couple of years, always planning to have it replaced when I got around to it, and sold it to a friend (with full disclosure). No problems at all.
At worst, you might need a dropout or tube replacement, but with lugged steel that's not a death sentence.