Check with Jeff Mear's for folding rear seat pedals http://www.airkitllc.com Another great Jim Wining's idea.

Mears%20pedals%202.jpg


Mears%20pedals%201.jpg


We usually have a few, but are out of stock currently.
 
They work very well.

Not really for ground (training) use though as it is possible for the clamp to slip under strong pressure. The front seater has the leverage. Common sense and physics rule!