Do I require to vary the boost pressure with respect to an increase or decrease of throttle (engine rpm)?
*Note: The supercharger is electrically driven (motor) and not by engine crankshaft.
I gotta first apologize to user16006. I was looking for ways to stop you from modifying your motorcycle because the idea seemed silly. But who am I to do that? I mean, modding cars is one of my passions. I'm gonna stop being a dumbass and try to help you.
On your motorcycle, you want to limit boost pressure to when the throttle is fully open. The reason is that the engine is tuned to provide the most fuel and timing under those conditions. If you are not going full throttle, the engine is tuned to save fuel. When you boost an engine you need more fuel. To limit damaging the engine, just turn on the supercharger during full throttle with a microswitch.
Now, you are going to be putting more air into the engine. You need to balance out the ratio between air/fuel. A fuel injected engine means you will either need a bigger injector from a bigger CC engine, or put another injector that only works when the supercharger does.
You are also going to need to tune the engine in order to get the most performance out of it. It depends on how much boost you can get out of it. Get yourself a boost gauge from a diesel vehicle (you can find those in scrap yards) and hook it to the intake manifold. For every .3 bar of boost you are going to want to test removing one degree of timing.
Now, to directly answer your question:
Do I require to vary boost pressure with respect to increase or decrease of throttle (engine rpm)?
In your case the answer is yes.
Good luck OP! :)
I'm going to say it's not necessary here.
An "electric supercharger" like a leaf blower is more a pump than a compressor. The amount of extra air that isn't that much; it should be quite readily compensated for by the fuel injection management.