The bolt you see right above where the handle turns is the handle bar clamp. And if it's been on a while you'll need to take a piece of strong wood and hold it on the bolt, when it's lossened a bit, and hit it with a hammer to fully loosen the handle bars. Hand brakes should come with clamps to put on the hadle bars, and if you look at bikes that have hand brake, you'll see how to route the cable. The only problwem is if your bike doesn't have the part taht the brake would screw to at the wheel. Then you'll have to improvise.
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The bolt you see right above where the handle turns is the handle bar clamp. And if it's been on a while you'll need to take a piece of strong wood and hold it on the bolt, when it's lossened a bit, and hit it with a hammer to fully loosen the handle bars.
Hand brakes should come with clamps to put on the hadle bars, and if you look at bikes that have hand brake, you'll see how to route the cable. The only problwem is if your bike doesn't have the part taht the brake would screw to at the wheel. Then you'll have to improvise.