Around 5 months ago I was riding My Saxon when all of a sudden the rear Gear acted up and went round the back wheel and pulled me to a stop. I managed to figure that a cable had come loose, so I put it back on and continued cautiously. Then around 10 mins later I was going a bit faster and the whole rear Derailleur totally snapped into two pieces causing loud vibrating noises to occur and one pice to start moving towards the front. I managed to get it to a bike shop and it was repaired. It was £30 to repair (£15 new gear, 15 workmanship)
The shop told me that the bike sustained serious damage to the rear swing arm and was lucky to be able to fix it.
I would like to know how serious these 'Techs', or Breakdowns are and how common they are?
i had a similar expericene on my old bike a carrera vulcan, wasn't the bike fault, i was riding thought a big pile of leaves which jammed up the chain. no serious damage because it had a replacable rear mech, would want to do it often cause rear mechs are about 10-15 quid
If your swingarm is steel (probably is) then they would have had to bend the derailleur hanger back into shape which steel can handle most of the time. If it was really badly bent they may have been worried it wouldn't go straight and maybe have lasting damage. Aluminium bikes have a replaceable derailler hanger as aluminium does not handle being bent back into shape very well so you replace the hanger if it gets damaged.
Hard to tell from your description what happened to make your mech (Derailleur) blow up 🙂 Rest assured it is not something that happens too frequently, tends to be one of the limit screws being adjusted wrongly or the mech hanger being bent from an impact which can make the mech go into the spokes.
