Is there any reason for me to have a higher volt/watt motor?

[Gary Shannon]

I have a Hilltopper 250W 24V front wheel on my 7-speed Schwinn. I don't use it for sport, just for day-to-day transportation. (I almost never use my car any more.) My terrain is flat city roads, and my typical trip is 2 to 4 miles one way.My kit has no throttle, just a push button to kick in the motor.

Most of the time I pedal in gear 5, and just use the motor for assist when I get below 10 MPH, and usually only goose myself until I'm back up to 12-14 MPH. Even pulling a bike trailer loaded with 20 pounds of groceries, I have no trouble cruising along at 12 MPH or so, although I do use the motor more when I'm fully loaded. (I'm only 150 lbs myself.) I don't need more speed than that since, at age 72, my reaction time isn't as quick as it used to be, and I find 15 MPH to be very comfortable, and 20 MPH to be a little on the "break-neck" side for me. hehe.

So as far as power is concerned, I seem to have all I need. What I'm wondering is, is there any efficiency advantage to a higher voltage, or higher power motor? Could I maybe get more range, or less battery wear by using a system that has more power than I really need, rather than pushing my 250W motor harder? I see that so many bikes use higher voltages and wattages, even when they are still topped out at 20MPH, so I assume there must be some advantage.

I'm also looking into these issues because I'm thinking about making a home-built trike just for fun, and as a better grocery-getter.

 

[Trail Cruiser]

For your application as you described, I think you are perfectly fine with what you have.

 

[bob armani]

I have a Hilltopper 250W 24V front wheel on my 7-speed Schwinn. I don't use it for sport, just for day-to-day transportation. (I almost never use my car any more.) My terrain is flat city roads, and my typical trip is 2 to 4 miles one way.My kit has no throttle, just a push button to kick in the motor.

Most of the time I pedal in gear 5, and just use the motor for assist when I get below 10 MPH, and usually only goose myself until I'm back up to 12-14 MPH. Even pulling a bike trailer loaded with 20 pounds of groceries, I have no trouble cruising along at 12 MPH or so, although I do use the motor more when I'm fully loaded. (I'm only 150 lbs myself.) I don't need more speed than that since, at age 72, my reaction time isn't as quick as it used to be, and I find 15 MPH to be very comfortable, and 20 MPH to be a little on the "break-neck" side for me. hehe.

So as far as power is concerned, I seem to have all I need. What I'm wondering is, is there any efficiency advantage to a higher voltage, or higher power motor? Could I maybe get more range, or less battery wear by using a system that has more power than I really need, rather than pushing my 250W motor harder? I see that so many bikes use higher voltages and wattages, even when they are still topped out at 20MPH, so I assume there must be some advantage.

I'm also looking into these issues because I'm thinking about making a home-built trike just for fun, and as a better grocery-getter.

Gary-I agree with Mark's comment. You are only 150lbs and with a 250 watt motor, sounds like it is pushing you just fine. I asked the same question when purchasing my ebike. I am at 135lbs and my 350 watt motor on my ebike pushes me along at fast and furious speeds that are more than adequate. I can top out at 22.5 mph without a whole lot of exertion I asked about a 500 watt motor and they indicated it is too much power for someone in my weight class.

I like the concept of the Hilltopper. I was thinking on making one of my mtn bikes into an electric with the kit. Sounds like it is performing well! Ride safe!

 

[emco5]

....Hilltopper 250W 24V…. is there any efficiency advantage to a higher voltage, or higher power motor?… I'm also looking into these issues because I'm thinking about making a home-built trike just for fun, and as a better grocery-getter.

If you upgraded to Clean Republic’s 350-watt 36-volt Horizon system you would get their frame-mounted battery with LED meter. Simple hub systems like their Hill Topper lack battery info, so people tend to recharge too frequently. The felt power from the 350 compared to the 250 will be a welcome surprise. It will climb hills and haul a lot of heavy groceries with much less effort than the smaller hub. That extra energy, and the 350 kit's thumb throttle, will allow you to be more conservative with battery drain, unlike the on/off wide-open control of the 250.

(Link Removed - No Longer Exists)

 

[Gary Shannon]

If you upgraded to Clean Republic’s 350-watt 36-volt Horizon system you would get their frame-mounted battery with LED meter. Simple hub systems like their Hill Topper lack battery info, so people tend to recharge too frequently. The felt power from the 350 compared to the 250 will be a welcome surprise. It will climb hills and haul a lot of heavy groceries with much less effort than the smaller hub. That extra energy, and the 350 kit's thumb throttle, will allow you to be more conservative with battery drain, unlike the on/off wide-open control of the 250.

(Link Removed - No Longer Exists)

Thanks for that info. My next project is going to be a trike, so I'm guessing that I might appreciate the extra power with a heavier bike.


I'm also trying to learn more about battery packs and instrumentation. I have a head start since I'm a retired engineer, so I'm pretty sure I can learn enough about it to get myself into trouble with home brewing! (If nothing else, I'll discover new ways to make clouds smoke! hehe) I'm building a custom battery box from an ammo storage box, and I am thinking about building up a battery from scratch to go into the box. I imagine I could add monitoring at the same time. I do hate charging the battery blind.