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NYC2LA:
Hi-
New to all this EV stuff...I'm a tinkerer at heart and need a new project.  I was wondering about putting the front hub assemble on the rear (of course I would tinker to make it all fit--and be safe), and ditching the pedals, chain rings, etc., and just make the bike an electric scooter.  Is the motor powerful enough to cruise like a scooter?  Hills, flats, etc?   

myelectricbike:
You don't need to tinker. Golden makes a rear wheel kit... but consider this...  your bike weights 20-30 lbs which is unevenly distriuted with 10 up front and 20 in the rear. You add the motor which is 18 lbs but the old wheel was 3 so you add only 15. Now add the battery pack which is 30 and then your weight which is 175 (i'm guessing) distributed also 2 to 3.

Lets see now... rear: 15+15+30+116.6 = 226.6 and front: 15+58.4 = 68.4.. that's a lot more weight in the rear.

NYC2LA:
yes, but is the rear wider?  does it have a different hub to fit the rear chain wheels (sprocket cluster)?  I wouldn't want any of this if I can do away with it. 
The main point of the question was really about the power of the motor.  Does it have enough to carry 200+ pounds of human & machine?
Also, I am DEFINITELY naive when it comes to electric motors.  I read in other discussions that someone put a 48 watt battery to it, to get more power.  Is that what cranks these faster?  More wattage in the battery?  How does wattage "compare" (I'm sure I'm using the wrong word) with amps?  The motor is advertised as 450 but with a max of 600...I don't follow how this works.  Anyone care to explain?
thanx in advance.

G

myelectricbike:
Sounds like you'd be interested in learning more about electricity and BLDC motors. The Wikipedia articles are where I would start. As for Golden ebike conversion kits, yes, the wheels do have sufficient torque and heavy duty spokes to handle 200 lbs (The ratings are based on 175 lbs, however) with motor rating at 250 and 500 watts, at 24 and 36 volts respectively (although some claim they can handle 48 volts and 800 to 1,000 watts). Federal law, however, limits ebikes to 750 watts and a top speed of 20 mph.

OneEye:
The lower listed wattage rating (450) is the "continuous" wattage.  This is the most power you can put through the motor CONTINUOUSLY without it melting down or shortening its service life significantly.  The upper wattage rating (600) is the "peak" wattage.  You can pump that much power through the motor for a short time (such as starts or short hills) but if you keep it up beyond a short period of time you will start melting things in the motor.  Heat dissipation is one of the main limits on electric motors.

If the controllers &c can handle the 48V, as long as you keep the total power pumped through the system to within the original guidelines I think you will be alright.  The problem is it becomes very easy to pump too much power through the system with the additional voltage.  One benefit of running at 48 volts while limiting yourself to the original motor power limits should be an extended range (since you have 4 batteries instead of three).  You have certainly voided your warranty if you do this though.

The other thing to note, is that at low rpm and high torque (such as starting from a stop) the motor is very inefficient.  If you pedal while starting and on hills, and let the motor keep you at speed while cruising on the flats, it should be a pretty good way to extend your range.  By eliminating the pedals and making it a scooter you lose this ability.

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