Originally Posted by Toothy
The wheel is pushed all the way up in the drop outs. I guess in need to lower the wheel, remove a link and then push back up till tight?
If the drop-outs are horizontal then moving the axle 'back' will tighten the chain. If the chain is the original one I'm not clear on why it should be loose.
Is it a single speed bike or does it have external gears (multiple rear sprockets) or a cassette? If it has a multi-speed hub, internal gears, then the chain tension should be adjustable by moving the wheel back.
EDIT: Just thought about this. Could the frame have been for gears and have drop-outs that are not horizontal and you have installed a single speed or internally geared hub? Bikes with derailers and cassettes usually don't have horizontal drop-outs because the derailer takes up the chain slack.