incorrect information you've been supplied with bender.
Nearly all bikes are dyno'd for maximum power in '4th' gear. Typically I believe this is because this is the highest gear (of a usual six) that can be guarenteed to max out revs wise. When you see dyno charts in magazines they are all done in 4th gear, which dispels this concept of restricted HP in the higher gears - where you actually need it the most due to air pressure more than anything.
The only bikes that change their horsepower have power mode selection buttons (S1000RR, Diavel, etc). But when you change power mode the (selected) HP remains consistent in all the gears.
A few bikes have had manufacturer imposed restrictions to Torque. Examples of this include certain models of the ZZR1400, the Super Tenere and until this model year the Rocket 3 Roadster, which actually had Lb.Ft restriction in it's first three gears I believe.
With the advent of smoothness improvements to fly by wire throttle control and traction control becoming more widely available and sophisticated on even non sports bikes (Multistrada, eXplorer, GS even now) expect any torque restrictions to be phased out IMPO.
Without hopefully sounding patronising, for those that do not know the difference between HP and Torque, I think of it in terms of a boxer. How hard he can punch represents his Torque. How frequently he can repeat those punches represents his HP. To move big heavy objects like Harleys from stationery you need Torque. To keep anything going fast you need HP and good aerodynamics.
When you combine strong Torque, high HP and good aerodynamics you get bikes like the ZZR1400, which can be very fast, despite a weight penalty even.
For it's genre the CrossTourer is a relatively good balance of Torque (best in Adv Tourer class) and HP (up there too) and aerodynamics (sacrifices a little protection for fair slipperiness); but like me, losing a few pounds wouldn't do it any harm.