Thanks Prathmann, I like that...she has a neural muscular disorder that is debilitating but not crippling, she can pedal but she no longer has the balance to ride anymore. plus she will have to be able to stop pedaling to rest, I don't know enough about tandem bikes, is the secondary person able to stop pedaling and coast or will the pedals keep turning as long as the primary is pedaling, or visa-versa?