As a recovering Head-Fi.org addict (by recovering, I mean, I got married and can't afford it anymore, not that it matters with kids anyway...)
I've owned many awesome headphones and had the pleasure of listening to others.
The question always asked is
'what kind of music do you listen to?'The Koss KSC75's are cheap and very good. I recommend them, for biking...at least with me, there is an element of abuse that comes with physical activity...KSC75's were my go to for the gym/mountain biking for that very reason.
The second question is: in ear, on ear, or around ear preference?
If you want an On Ear can, and you like metal or brighter sound, the Grado SR60's are fantastic...retro looks and they take a beating too, lots of mods, and tons of fixes.
If you want in ear, I can't help you...I have the Sennheiser MX300's, but I wouldn't say they are amazing...they are better than Apple's ibuds, but nothing close to what I've compared.
If you want around ear, I recommend my current can--Sennheiser HD449's. They are small, but they don't fold. They are closed, so it will isolate some of the noise but then again, others will not be able to hear it. I use them for gaming and music...
Here is something to look around and see for yourself.
http://www.head-fi.org/products/category/headphonesGood luck! If you want to talk hi-fi, hit me up.