The LED's use much less power to produce their light so, per watt they produce more lumen's of brightness.
A Philips article says an incandescent bulb produces about 13 lumens per watt of power used.
It goes on to say that a non-hyped honest estimate of a LED shows they produce about 40 lumens per watt.
Assuming this to be true, a 65 watt incandescent bulb will produce about 845 lumen.
To produce 845 lumen of light a LED would use about 21 watts.
The article also mentions that with a incandescent bulb the lumen output is directed in all directions while the LEDs are usually designed to direct their light in one direction.
Said another way, using LED's for the lights on a motorcycle will greatly reduce the power they use to produce the same amount of light.
They can replace all of the bulbs on a motorcycle (if the light base is the same as the existing one) but as has been shown in another topic here replacing the turn signal bulbs can be a PITA. That's because the LED's low power use won't let the turn signal flasher work properly. They also need the proper + and - battery power to be connected to the correct terminal in the light socket because if this isn't what they expect to see they won't light. The turn signal indicator light may need to have the wiring modified too.
This isn't a problem for most of the lights because the RE's power and ground is correct on the headlight, parking lights and tail light.