I just bought my very first bike and am so excited! Its a 1978 Honda CB125T with the full power (16.5hp) motor. Rides really nicely and plenty fast enough for my first bike. It is generally in great original condition, but the front brake is worse than useless. Literally pulling as hard as I can on the lever makes hardly any difference and I can walk the bike forward with the brake fully on.
So I was hoping someone could offer some advice on how to strip the brake and possible problems / remedies because as it is it is unsafe and will fail it's mot. Or are replacement brakes available?
As a side issue the seller advised the tappets need looking at. Being new to bikes I have no idea what the engine should sound like, although it is a little rattly. I've bought a haynes manual but are there any other resources to help me strip the engine and be able to sought this issue?

Please help.

I didn't find the right solution from the Internet.

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