[JPTolson]

There would also be the Cuyahoga where one paddles through the national park and a bike shuttle via the towpath that runs along the river.

Also, the Allegheny has a riverside bike trail in the Franklin, PA area.

Not sure about how close the Stavich Trail stays to the lower Mahoning, but that may be another possibilty.

And the one I'm most familiar with is the C&O Canal Towpath that runs along the Potomac River from Cumberland, Maryland to Washington, DC.

Never stopped to think about it before, but there must be lots of bike trails along rivers these days