In ´85, the bike is rated at 145 at the crank. There is much loss to the rear wheel, which would normally dyno at 98-108hp. The shaft drive is a HP robbing item. I believe the so-called "detune" after the first year was in the ignition module by changing the ignition timing curve. Ignition timing is set, and can only be changed by an after market(dyna 3000) ignition. Just by changing this ignition module, I´ve noticed a great bit of difference.