The red lines area the baseline before any tuning was done. Blue lines are final tuning results.

Generic stock twin cam dyno

Harley doesn't publish HP ratings, but the stock twin cam engines typically produce high-sixty's (68 is considered typical) horsepower at the crank. Factory rates torque at 85 lbs. I couldn't run my stock engine on the dyno as a baseline because it hadn't been broken in (jugs swapped before it was ridden).

This dyno run is for a 95", 10.5 compression, and Rinehart True Duals. It peaked at 93 HP and 100 lbs torque at the rear wheel. Latus typically sees 100 to 105 HP if this setup were run with Bassani 2-into-1 pipes, but I went with the duals for a bagger.

"Most" consider drive train loss to be 12 or 13%. Others dyno guys have told me they see a 15% and occasionally even greater loss. Taking those number, we can figure there is between 105 and 109 HP at the crank. That gives a 54% or greater increase in HP.