Jury rigging is often carried out as required by emergency situations where repairs must be made using only the tools and supplies that are on hand. For example, a good friend of ours here at Cyclepedia.com was out riding in the woods having a great time when suddenly he found himself laying on the ground with a broken clutch lever perch. He found some twine and duct tape in the glove box of an unlocked truck at a construction site and was able to jury rig the perch so he could operate it long enough to get home.
Unfortunately, there are some professional jury riggers out there who are just shoddy mechanics – for example a Kawasaki KLX110 just came into our shop to have the foot peg bracket replaced with a stronger aftermarket style complete with a skid plate. When our technician went to remove the bolts he realized that someone had replaced the stock hardware with standard grade wood screws and coated them with silicon. The bolts extended well up into the engine internals. The engine cases were beyond repair and had to be replaced. The bike was completed jury rigged!