In answer to "The Big Question" my personal answer would be ~ Fully functional pedal drive that BOTH allows the operator to ride the bike with relative ease on pedal power alone AND provide meaningful input by continuing to pedal that directly and noticably results in improvement of the performance of the bike along the entire speed range from initial acceleration from a dead stop to the top speed when under motor power and is built with the full intentions of the rider pedaling most if not all of the time. A Mo-Ped/Scooter does not meet that most important criteria in my mind and the pedals are just mainly for show. An e-bike or motorized-bicycle most certainly does. The power asisted bike I ride most often and that I commute on multiple times every week on a 10+ mile one way commute will go just under 20-mph under motor power alone on the flat, by continuing to peddle I can push my cruising speed on the flat up to slightly over 25-mph which is noticeably faster, I climb hills noticeably faster if I continue to pedal, and I can accelerate from a dead stop nearly twice as fast by pedaling hard as well as engaging the motor. In every way unless I'm beat tired there is more then enough encouragement built into the system to keep me pedaling strong while the motor is engaged.

If you can't make a noticeable difference by continuing to pedal that is a strong enough incentive to keep you pedaling then you are beyond the "bicycle" status and have just built yourself another Mo-Ped. That is where the line lies in my mind. It is the emphasis on preserving the human power output as a strong part of the equation that makes the difference. Both a Mo-Ped/Scooter and an e-bike/motorized-bicycle can and should be able to keep up with 25-mph in town traffic in my mind and fully mix with traffic at that speed but shouldn't be able to go much faster then that without a big down-hill section and/or a strong tail wind (you can also build yourself a lower powered e-bike if you want as well but unless your handicapped I don't see the point and would just use a pedal only bike for lower speeds in my mind and for short distances I can go that fast on a light weight pedal bike just can't maintain for distance).

Anyway, that's where I draw the line as far as speed, but speed isn't the big question to me, and the total power however it is measured is even further down on the list. THE BIG QUESTION to me is whether the human power output is fully taken advantage of and is considered a primary output in the hybrid drive system. Are the pedals there for real and set-up to be used most of the time, or are they just there for show to meet legal requirements and they are hardly usable and just used as a place to rest your feet while the motor pulls your fat @$$ around ******************** That is THE BIG QUESTION to me.


*Added Note: The speeds I list are for a "commuterized" mountain bike type set-up either pedal only power or hybrid human/motor power. A road bike is not rugged enough for a reliable daily commuter on the roads I ride on up here. Medium Weight Sturdy Mountain Bike Frame + Tough, Minimum-36spoke (48 is better), Double Wall Mountain Wheels + Puncture Resistant, Armored, 1.9"-2.25" Wide, Tough, Street Tread Tires + Fenders + Decent Rear OverWheel Cargo Rack + Good Lights Front & Rear is the kind of set-up you need for the roads up here for a reliable daily commuter whether you have a motor on it or not. "Running Light" (no cargo) I can push that kind of a set-up to 25-mph on the flat for a short sprint distance under pedal only power, maintainable distance speed on the flat under pedal power only is about 15-mph for that kind of a set-up. Running a motor and pedaling together lets me push up to 25-mph for distance without having to resort to a stripped down road bike that I can't depend on to go the distance with the conditions up here in the wilds of MT.