Originally Posted by europa

If you're replacing the hub, you need to buy a track hub, one that has the thread for the cog, plus a smaller thread cut in the opposite direction for a locking ring - your bmx hub doesn't have that.

Any bike shop should be able to get you a hub. Any wheel builder will be able to get one for you.

BUT, are the rims worth it?

It's often cheaper to go looking for a set of track wheels. Ebay, craigslist, even shops - the wheels on my son's track bike were bought, brand new but at half price, from a bike shop that was clearing wall space for new season's stock and I just happened to ask the right question at the right time. The frame came from a similar source, in this case, only one bloke in the shop remembered that old track frame covered in dust in the back of the store room. The wheels on my Europa were built specially for my be a local wheel builder, but built to the pathetic budget I had at the time.

It never hurts to walk into a shop and just ask.

Richard