As bike rebuilders, we   hardly ever run into proprietary components, ie components a manufacturer designs,  to specifically fit their type of bike, and no one else’s.  It’s worth-while salvaging  just about every old bike – because   you can use the parts  to repair all sorts of  other bikes.  The other day, though, we struck an exception, with an old Mongoose BMX. ……  .

 It arrived with parts missing, so I took it to Wiltja College, for the “Scrap-heap Challenge”, bike-building…