6. At idle, a deep rumble resonated through the parking lot and at higher revs it howled. Stock, the BMW made 181 HP @ 78 LB-FT. Full system installed and tuned resulted in five more ponies and two LB-FT of torque for a total of 186 HP @ 80 LB-FT. From 7K RPM to redline the bike pulls noticeably harder and smoother, thanks in part to the serious weight loss.