Raichu's electricity can reach 100,000 volts and can make an Indian elephant faint. It also has Quick Attack.
Elecman has superhuman calculation speed and razor-sharp judgement. He's also pretty fast and his Thunder Beam can kill Megaman in 1-3 shots (based on gameplay).
gameplay. Raichu can put a dragonite unconcious. plus has a variety of attacks like earthquake, surf, hyperbeam, double team, agility, the list goes on, metronome (which opens up the entire list)... raichu takes half damage from elec man's attacks. so yeah raichu takes this
Gender: Male Location: Following the Source of Light.
I should think Elec Man would tank most of Raichu's electric attacks, though. If Raichu has some stone attacks, oil attacks or a blade attack that can match the Rolling Cutter, it might be able to do some damage. These are all Elec Man's weaknesses.
It should also be considered that one of Elec Man's Thunder Beam pumps out five times the voltage that Raichu can store in its body. It should also be mentioned that until Quick Man, Elec Man was the fastest Robot Master around.