they keep your chain tight
let me rephrase what the previous user said. i ride bmx and i know almost eveything about bikes. your chain gets loose because your frame dropouts are striped. when you pedal the strip is going towards the frame so your chain gets loose. the only best idea is to get washer, bring to bike shop to resurface it flat and recreate the integrated chain tensioner, or go on daqnscom.com to buy some chain tensioners that work really well.
inox or chain lube from a bike shop
I would suspect that there are problems with the hub. Even if it the quick release or nuts are tights, loose bearings will cause the wheel to wobble or feel sloppy.
It depends on the length of the chainstays on your frame.
If you're using a 1/2 x 3/32 chain (or "10-speed chain") on your BMX bike, you're out of luck. You can't half-link those chains. If you have a 1/2 x 1/8" chain, you can buy what's called a "half-link" (go figure!). I've seen them range from $2 to $10 and they go in place of 1 1/2 links in your chain to get you that ideal chain length if you find you don't have enough drop-out adjustment to prevent either a too loose or too tight chain.
you can find a BMX bike in halfords
Two, but this is not the same as how many speeds the BMX bike in question has. A BMX bike has a sprocket in the front, and a cog in the back and each is a gear, but is considered a single speed bicycle because two gears and a chain are required for transmission of rotational force from the crankset to the rear wheel.
The bmx thruster rampage bike is a exellent bike
One can buy a custom BMX bike in Las Vegas from a few stores. One can get a BMX custom made from 'Just BMX', 'Bolder BMX', 'Bike World' and 'Vegas Bike Store'.
A chain is a chain, it hasn't got any gears in it. But if you run it across a pair of sprockets you can create a gearing ratio.
A hyper is better