why are bicycle chains always on the right hand side?

[63336]

Is there a real reason for this?

[Clanad]

There are bicycles with the chains and pedals on the left side... however, since most bolts and nuts turn to the right to tighten, right sided sprockets will tend to tighten and not loosen bolts and nuts during their rotation.  Left handed sprockets and chains will loosen that type of right-handed nuts, hence the nuts and bolts on such drives are left handed and turned the opposite direction for maintenance.  This results in the average owner having difficulty with such nuts and bolts, since most people are used to the standard right-hand type.  Additionally, the old rule of "its always been that way" probably has a lot to do with it...

[landie]

If you put the chains on the left it wouldn't reach the sprockets. :-)

[Bob A Job]

Thinking about it most people 'mount' a bicycle from the left hand side, maybe to leave extra romm for this manouver?!?!

[landie]

It depends which side of the road you ride, I guess Bob a Job.