The best option would be to find a local bicycle co-op and offer them the parts.
(They would probably welcome bikes, rims, and tools.)
You may not be near a co-op; if that's the case, there are numerous "pay it forward" threads on bicycle forums, but you'd end up paying postage; useful for small or esoteric parts.
(I've given away a lot of stuff that way.)
You could also try Freecycle , but since that's more of a general audience, I doubt many people on those lists would even know what, say, a bottom bracket is , let alone how to use it.
For giving away a complete working bike, this might be an excellent option.
(Hey, their logo includes a guitar and a bike!)
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If you've tried all of the charities and bike co-ops in your area and are still left with a pile of parts, you could try offering them (free or for a nominal charge) to the bike hackers over on the Atomic Zombie Forums (or somewhere similar).
If they're parts then they'll probably be glad of them, if they're frames then they'll probably only take them if they're not aluminium.
You can never have too many tools.
Alternatively, depending on how much stuff you've got buy an arc welder and build your own trike or recumbent - plans here: Atomic Zombie Extreme Machines
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I would just look for ads and/or post an ad on craigslist/kijiji.
I just saw an ad last week for someone looking for "old bike parts in any condition".
I kept the parts that I knew I could fix and that I would need and dropped the rest off to him.
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In the Chicago area, donate those parts to Working Bikes Cooperative.
Working Bikes is a 501c3 non-profit with the goal of diverting used bicycles and parts from the waste stream.
Bikes and parts are redistributed to partners in developing countries, primarily in Africa and Central America; to local partners in Chicago; and sold as the means to fund the organization.
www.workingbikes.org for more info.
Working Bikes has drop off locations in Illinois, Wisconsin, Iowa, Indiana and more.
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I have many old bikes, parts, specific tools, etc. Where can I give them to?
I've got numerous bikes, bike frames, wheels, etc.that I'd like to donate
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Bike parts can be donated at local bike coops or charities. Parts can also be offered on forums such as Freecycle or Atomic Zombie Forums. Finally, another oprion is posting an ad on craigslist or kijiji. A good solution would be to donate the parts to a bicycle co-op, local or otherwise. Alternatively, you might consider offering or selling the parts to a bicycle community, for instance to members of the Atomic Zombie Forums or Freecycle. There are also a number of pay-it-forward schemes on bicycle forums. Finally, you may post or answer an add on advertisements websites, such as Craigslist.
A good solution would be to donate the parts to a bicycle co-op, local or otherwise. There are a number of pay-it-forward schemes on bicycle forums. You might consider offering or selling the parts to a bicycle community, for instance to members of the Atomic Zombie Forums or Freecycle. You may post or answer an add on advertisements websites, such as Craigslist.