Motorcycle Questions? Ask a Mechanic.
The dealer's explanation/excuse is completely untrue. The brake pedal should not pulse unless the rear wheel is trying to slide.
If you and aren't trying to slide the wheel, you need to get someone more experienced, or more honest, to check the bike for you. The brake should be smooth and strong with fairly light pedal pressure.
And, just for your information, the new ABS system links your front and rear brakes and both operate at factory designed biases, or percentages, when hitting the rear brake pedal.
I would suggest finding another shop.
I hope this helps. Thanks, P.J.