3wheels1life

Hello everyone,

I'm thinking of getting a front hub motor for my Sun EZ-1 SC.
This is a 16" inch wheel.
(a rear motor won't work because I plan to get an Extrawheel).
How many volts and watts should I get?
I'd like to be able to ride at least 6 hours per charge @ 20mph.
Also, should I get a casted hub or a spoked hub? I'm thinking of a casted hub (with built in hub motor) because it will not need to be respoked or trued. (goldenmotor dot com sells one with a built in controller available with either a spoked or a casted rim [any experience with this model?]).
Do you have any front rack battery mount suggestions (or will a front rack even be compatible with my bike)?

Thank you so much. I look forward to hearing from you.

-3wheels1life

lwik

I'm still in the process of getting my set up but it depends on a lot of factors mainly weight. But it is also ambitious to get 120 miles per charge. You can do it but you might have to carry thousands of dollars worth of batteries and lots of extra weight and space to put them.

350htrr

I don't know of any battery setup that can do 20 MPH for 6Hrs, the most I have seen is 18 MPH for 2.5Hrs...

chvid

I've got a Sun EZ1 with a front hub motor. Due to the small size of the wheel you need a "fast wind" motor that can assist up to say 25mph. I'm using the "no-longer-available-in-North-America" Crystalyte 404 hub motor, which is very quiet, fast and well-matched in power. If you can find one of these motors used, or a Crystalyte 405 motor (typically in a 20" wheel), either could be used, the 405 would need to be respoked into the 16" wheel. Another possibility is a fast wind Nine-Continent motor - typically designated a 2805, but the spokes would be incredibly short from the rim of the motor to the 16" rim, might not work - those motors (and the Goldens and Conhis direct drives) are much bigger than the Crystalyte 400x series. You could also get a 20" geared hub motor from emissions-free.com - they are a reliable supplier, and have a variety of fast wind motors as well. The 16" wheel is a challenge - if you don't want a slow moving torque monster - but a fast-moving wheel. You could also run a small non-fast-wind motor at a higher voltage, to get the rpm up. Another possibility is a direct drive Aotema motor - about the same size as the Crystalytes, used at a higher voltage to get the rpm on. You will have to do some research on small, fast wind motors. The geared motors have nice torque but the mini-geared types are not that fast wind, and running them at higher voltages to get the no-load speed up could burn them out (or burn out an overvolted controller), without tuning down the controller shunt to reduce the amperage accordingly.
I'm using Cute 100 mini-motors on my 20" wheels, but I'm having issues finding controllers that are matched to those at 48V.

I often run two 48V 15Ahr Ping packs in parallel, carried low under the seat on a mid-rack (easily available). That's well balanced, and a good spot for them on the EZ-1 - about 30 pounds of battery. That will put you many many miles down the road - I peddle moderately at all times, and I'm good for 85-90 miles with that much battery, in low-moderately hilly conditions.

3wheels1life

Thanks everyone for replying. I appreciate your input.

Would a 48v 250w hub motor + Ping 48v 30ah LiFePO4 last 6 hours?
What do you think is the best brand of hub motor?
I'm thinking the motor would use 5a per hour, and for 6 hours = 30 ah.
Is this correct?

Thanks.

-3wheels1life

chvid

A small brushless geared hub motor like the Cute 100 can run with the KU93 controller (www.bmsbattery.com) at 48V, with one of its two shunt wires cut inside the controller case. That is a 48V controller, and is rated at 22 amps. I just tested one last week with one of its shunts removed, and it was bang on at 12 amps max output with my 48V15Ahr ping batttery. That is close to the optimum power for those small "250 watt" motors - 600 watts. With both shunts, the motor would eventually be damaged. Pulling 5 amps for an hour, at 52V, would be around 300 watts of power over that period. That is more than I generally use. Most of the time on the flats my bikes are maybe around 200 watts when I'm pedalling, and often lower. I do like the small motors, but they won't be very fast in a 16" wheel. The rpms per volt is not enough (typically around 350 rpm at 52V). I use 52 volts for reference as my 48V Ping packs are typically running around that voltage most of the time.