Tyler Paul

your supposed to be able to pedal backwards and not going anywhere but when you and doing a fakie (going backwards on a bike). You have to pedal backwards on a bike to keep moving because if you don’t pedal backwards to back wheel will jam and you will stop. Pedaling backwards faster while you are in a fakie will not make you travel backwards and faster.

It is impossible to make you bike be able to go backwards by pedaling from being stationary. Unless you swapped you back wheels round to it was LHD (left hand drive) instead of RHD but then you when you pedaled forwards you would just be spinning the cranks round and not going anywhere.
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Riding and fixing BMX bikes for 3 years

You need to convert it to a fixed gear bike. Whichever direction you turn the pedals is the direction you go. The thing is, you will not be able to coast. If your wheels are spinning, the cranks are going to be spinning in the same direction. I myself am not very familiar with bmx bikes in general, but I believe that Surly track cogs are designed to work on bmx hubs, but they even say that it’s not the recommended use because usually you use a specialized track hub that has a reverse threaded section on it, so that you can put on a lockring that will keep the cog from spinning off when you go backwards or resist against the momentum of the pedals (usually to slow down or stop while going forward). I have heard of some people using Loctite to keep a tack cog on without a lockring (known as a suicide hub), and I’ve also heard of people using bottom bracket lockrings on non-track hubs, but the lock ring can still spin off since it isn’t reverse threaded. But those aren’t the safest ideas, and really should only be done at your own risk. You could also get a new rear wheel built around a track hub I think, but that might be out of your price range.

You might also be interested in fixed-gear freestyling, which is usually done on track or converted road frames instead of bmx ones, but then again, most fixed-gear info is directed to folks with track or road frames.

http://en.wikipedia.org/wiki/Fixed-gear_bicycle
http://www.youtube.com/watch?v=NiJx2kNLFZA&feature=related
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Alex,

You said you know all that but what you said DOESNT WORK. Lhd means you have a left-side drivetrain it has nothing to do with pedaling backwards. Obviously you dont know much about bmx at all.

Liam,

Bmx bikes are made to go forward when pedaling not backwards. Pedaling backwards allows you to go backwards but only because the driver on the hub isnt engaging. Pedaling backwards fast doesnt do anything but make you look dumb.
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you are probably getting confused with freecoasting, this uses a special hub which allows the bike to roll backwards without the pedals rotating.
see this; http://feelbmx.com/news/how-does-a-freecoaster-work-
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It is technically possible to do this, by having a fixed-wheel bike (with no freewheel, so pedalling backwards turns the rear wheel backwards).

However no-one except an acrobat can balance while riding looking the opposite direction, and there would also be the complication of in effect steering using the rear wheel, so it is really only useful for circus tricks, not for cycling as such.
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