SLAYERDUDE

If the leak is bad enough to cause revving you can cover the carb with your finger and the engine won't die immediately like it should.
Otherwise look for wetness around suspect leak areas, or brush soapy water around those areas and blow into the fuel line while covering the carb and exh (header removed) with your fingers and watch for tiny bubbles.
The front bearing seeping while doing this is normal, but not like you can just blow thru it.
You can also run with air cleaner on and spray nitro cleaner around/on suspect areas and if the idle drops or the engine dies, there's your leak.

Hope that helps.