This kit I bought from Amped Bikes (http://ampedbikes.com/store.html
) is the 350 - 450 @ 36v rated geared hub motor (rear wheel) cost me $400.00 shipped ( this was $50 off normal price for buying a second kit) with the newer disc brake mount in the casting of the hub motor case, not a bolt/screw-on attachment.
It arrived on-time 1/6/10 (shipped 12/30/09) I was very happy to see it since I had been working so hard to get the rest of the bike ready (mainly the battery pack). I had ordered this kit even before they had arrived from China, so I was very impressed that a full shipment from China had arrived on 12/19/09, and they were tested and sent off so quickly. I had helped my father purchase one of the rear DD hub motors previously, so I was already impressed by their product and customer support has always been great, most times (with the exception of when there were spam bots attacking the Amped Bikes Forums, making it difficult to get a log-on at first, just had to send a direct email to amped bikes rather than rely on the automated service) emails were answered with-in a day or two. Items were well packaged and arrived in perfect condition.
Here are pics of the kit as received from Amped Bikes:
I was thrilled when I then tried this kit with my 52.8V 6.9AH battery pack, and felt a huge difference over the DD hub motor we have in the acceleration. The DD kit was being run on a 36v 9.2ah battery pack, so that is a definite factor in the difference in performance, but where this motor truly shined was in hill climbing.
I have confirmed via this site: http://www.mapmyride.com/create_new
that Singer Hill in Oregon City, is indeed a 7% grade hill, at least for .18 miles, and I have not done a motor only test yet (still cycling the batteries before I put too much load on them) but to compare with the DD motor, which I could only get marginal help up this stretch of hill, i.e. 7-8 MPH with pedaling, with the geared motor, I am able to get a SOLID 12MPH with moderate pedaling. This is huge compared to the fact that I would have to bust my guts to try and maintain 4-5 MPH up this stretch of hill with a standard bicycle.
I continued up the rest of the hill and was so excited that I wasn't paying attention to my Watt Meter, and managed to spike my amps enough to cause a few of the 28v Dewalt batteries in my pack to trip the over-current draw in the BMS of enough batteries, that I inadvertently tested both the LVC and the BMS of the batteries. All of a sudden I lost power, noticed a showing of only 24V!?!!
on my watt meter and noticed that the red "low" light was only dimly lit on the throttle (green=full, yellow=half & red=low .. normally all three lights are lit with a full charge)
Initially I was very concerned that my batteries were damaged, but later I realized the 24V (52V is nominal) was just showing that some of the BMS's had tripped on one but not both of the 28V packs that were in series, and I was pleased that the controller did it's job and shut down power after the supply had hit the LVC.
I have since received 2 more batteries in the mails so now I have 8 total 28v Dewalts wired 2s4p making it a 52.8V 9.2AH battery pack, and I have again gone up that same hill the entire 1.4 miles (according to http://www.mapmyride.com/create_new
it averages out to 5% the whole hill) using the throttle more carefully I am still able to work my way up to WOT with no problems and a speed of 12-15MPH.
More basic stats of the bike:
Total Bike weight: 59lbs Bike + rider (175lb rider) = 234 ******* EDIT ****** The motor is 9lbs as advertised, and my current battery pack is approximately 16-20lbs
No load speed: 31.6 MPH (It really is in that pic, but hard to see ... now you know why I want something else that I can really READ ... impossible in the rain to read this cycle computer)
Volts Minimum 50.28, 52.65 nominal (voltage drop under load going up the 1.4 mile hill with grades from 2-7%, averaging 5% over all)
Peak Watts: 722
Peak Amps 13.94 (controller is 15A - 22A burst)
The Dewalts are putting out just under 14A which is perfect for my application as the batteries don't quite reach the max out-put that the motor/controller are designed to operate at, so I'm confident I won't be stressing the motor too much, and I have never noticed even the slightest warming of the motor even after constant use climbing that hill for approx 1.5 miles with no rest.
Also, all tests thus far have been done in 40F-50F weather, 50/50 on the rain, I have not noticed any difference in performance in the dry vs the rain.
I use CST Long Life 26 x 1.75 tires such as these:
(not the same tire but almost identical tread pattern) and I run the pressure at about 48-50lbs, they are rated at 45.
Please let me know if I left out anything else you would like to know about this kit.
**** More Performance Data **** Preliminary results for Wh/Mi. are 12.368Wh/Mi. This is with 2 runs up and down a 5% grade hill nearby approximately 1 mile long, mixed in with some all motor and all pedaling testing for a total of 7.6Mi. I will do more of a scientific test (all motor) once the batteries are broke-in. I have about 10 cycles on 6 of the batteries, but the last 2 packs came in the mail later and have about half that many cycles.
*** As requested here is a pic of the drop-outs ***