I have a 55 Vdc @ 100 A/hr battery pack and am looking for advice on what I can expect for speed and range.
D&D motors recommended a 9 HP 72 Vdc motor, but no guidance on range and speed.
The bike is much heavier than what you want, but its what I got.
Tough love is welcome, as I'm looking for 50mph and 80 mile range.
Road King weighs, what, 800 pounds wet weight? Even with the big engine removed, you're probably looking at ~700 pounds converted. This is not a light bike.
I would guess your battery pack would do 20-30 miles at 50 mph.
To make your target range you will need to add significantly more battery or significantly drop your target speed for getting the range. At an actual pace of 35 mph you would get maybe 40-50 miles of range. A much lighter bike at 30-35 mph could probably do 80 miles with your battery pack.
A 9 hp motor pulling that weight would be best described as "leisurely". It could probably get you up to 50 mph, but it will not be fast.