Real Range? What can you get from a charge?

[indianajo]

Hmm..48v 20ah is 960wh...so 48 to 96 miles? Seems a bit unbelievable, but I can hope it's true!

Ha Ha Ha Ha Ha.
I have a 840 Wh battery. I ride sitting upright. On the 77 hills to my summer camp 30 miles away, the controller is red lighting voltage and sometimes cutting out up the last 2 or 3 modest hills. I ride ~ 6-8 mph up the hills and unpowered about 15-30 mph downhill. Gross weight is 300 lb with 70 lb bike & up to 60 lb groceries/supplies. Overall rise is 200' and only 3 of the hills have 15% sections.
I bought the battery to bring me home from a concert 50 miles away, but I'm afraid now to try it. Motor is a 1200 W geared hub motor. I'd be too tired after pedaling all the way out, and the host has all his AC outlets indoors so there wouldn't be any charging at the destination. Route to that venue is sort of flat, as people envision Indiana.
BTW there is not much to wear out in the 1000 W direct drive hub motor I bought. I had the cover off, it uses 6801 bearing which are available from the auto supply. Probably much better bearings than OEM since the evercool ones are not made in *****. I replaced DD with geared since I ride unpowered 23 of the 30 miles and DD hubs drag when not powered. BTW the bearing in my $221 geared hub motor is thumping after 4000 miles.

 

[Alex M]

550 wh? only seen batts rated at AH.

WH is more informative and is often used in ebike batteries specs.

48V 11AH battery contains 30% more energy than 36V*11AH and will ride 30% longer under similar conditions (in theory). In gasoline powered cars AH is an adequate measure because voltage is almost always the same.

 

[steve mercier]

I've read a lot and got the parts coming for my bike - 1000w hub motor, pas and throttle, 20ah battery. From what I've read that should be 30mph/30 miles.

What I've NOT read, seen in vidoes, or anyone talk about is REAL RANGE!

When I road bike trails on leg power alone I might do 20 miles or so. Most here are old RR lines so if you plan right you ride up grade to start and can have a much easier ride back when you're tired - 20 mph easy pedaling, 25 if you work at it some.

If I ride the roads here the hills do me in. 10% grades are common, and I live at one of the highest points i the county. So I don't ride much - hence the desire for an electric leg.

****

SO what is a realistic range? Does using pas vs throttle extend it? How much? I see most controllers have 3 to 5 assist levels - does using a lower assist level (either going slower or pedaling some) extend range and by how much?

I know in a car 55-60mph will give you 10%, or more, improvement in mileage (range) than driving 70-75 (alas, the speed limit). Is there a point on bikes where you lose more range than you gain in speed?

Play around with the variables on this range calculator to get an idea. You will learn stuff like slower equals farther etc . https://www.bosch-ebike.com/ca/service/range-assistant/

 

[harryS]

I've read a lot and got the parts coming for my bike - 1000w hub motor, pas and throttle, 20ah battery. From what I've read that should be 30mph/30 miles.
.....
SO what is a realistic range? Does using pas vs throttle extend it? How much? I see most controllers have 3 to 5 assist levels - does using a lower assist level (either going slower or pedaling some) extend range and by how much?

It will be interesting when you get your Voilamart kit put together, as you can give us your data point. What battery pack did you buy?

A poster over on the endless-sphere forum, who has built several 30 mph e-motorcycles, says it takes about 700 electrical watts to go 25 mph. Pull up a watt vs speed calculator, and they will predict at least 50% more watts to go 30 mph. Puts you at 1000 watts easily. That's 20A for a 48V battery, and lots of people can hit that with a Voilamart kit, but for how long. Half an hour is 15 miles. That's 1000 watts x 1/2 hour, 500 WH. I would expect you may get 20 miles. Hope you get a chance to test it out and see how bad this prediction goes.

 

[prof_fate]

Good to hear different facts/experiences on this.

I got a 20ah 48v pack, so 960wh if google did the math right.
Figure 80% usable capacity more or less, so 770wh.

Specs say motor/rim will rotate 470 rpm, 26" (used that, though the OD would be bigger with the tire on the 26 rim) is 36.6mph - I'm assuming 470 rpm is no-load, so it won't get quite that fast.

500wh=15 miles.. so 750 is 22 miles.

If 700w gets you 25mph, that's 30% less power than 30mph, so if it's all linear, 25mph from a 960wh pack would go about 30 miles. More if you pedal of course.

It will be interesting when you get your Voilamart kit put together, as you can give us your data point. What battery pack did you buy?

A poster over on the endless-sphere forum, who has built several 30 mph e-motorcycles, says it takes about 700 electrical watts to go 25 mph. Pull up a watt vs speed calculator, and they will predict at least 50% more watts to go 30 mph. Puts you at 1000 watts easily. That's 20A for a 48V battery, and lots of people can hit that with a Voilamart kit, but for how long. Half an hour is 15 miles. That's 1000 watts x 1/2 hour, 500 WH. I would expect you may get 20 miles. Hope you get a chance to test it out and see how bad this prediction goes.

 

[tomjasz]

Watt-hours is confusing to a broad cross-section of kit builders I've supported.
I also find it much more helpful to calculate from the Low Voltage Cutout (LVC).

I used a shunt and CA3 or a wattmeter to get numbers that work for my riding style.

 

[tomjasz]

wattmeter

Easily adapted to many bikes and a fantastic troubleshooting tool as well.

 

[Lightning P38]

The general rule of thumb is that the battery range is roughly 5-10% (in miles) of the battery capacity (in Watt-Hours), depending on how much motor assist you are using.

For example, if you have a 500wh battery, your range may vary from 25 miles to 50 miles depending on how much motor assist you are using on your ride.

If your average speed is roughly 10 mph, then you may get near 50 miles. If your average speed is somewhere near 20 mph (or if you riding on hilly terrains), you may get about 25 miles.

Looks like I will need to upgrade my 350 watt battery to a 700 watt battery...I like riding on pas 4 and 5 too much!

 

[Lightning P38]

Watt-hours is confusing to a broad cross-section of kit builders I've supported.
I also find it much more helpful to calculate from the Low Voltage Cutout (LVC).

I used a shunt and CA3 or a wattmeter to get numbers that work for my riding style.

Thomas,
What type of connectors are used with the wattmeter? Would I need to cut existing wiring harness to patch it in? I think it would help me measure battery stats to help keep me in a lower pas setting.

Also, do I just run the battery down and then measure voltage to find the Low Voltage Cutout?
Thanks,
Ken

 

[AHicks]

Lightning, my bet is, given more seat time, you'll eventually become a more efficient rider. I've always said there's a learning curve involved coming up to speed with an e-bike. There's more to it than a rookie is up for when he first sets out for sure! You need to balance PAS levels, correct gear, speeds, conditions, etc. Give yourself some time, relax a bit, and enjoy the bike for what it is for a bit. Then make whatever mods you think are necessary. -Al

 

[HonoraryOrange]

I've read a lot and got the parts coming for my bike - 1000w hub motor, pas and throttle, 20ah battery. From what I've read that should be 30mph/30 miles.

What I've NOT read, seen in vidoes, or anyone talk about is REAL RANGE!

When I road bike trails on leg power alone I might do 20 miles or so. Most here are old RR lines so if you plan right you ride up grade to start and can have a much easier ride back when you're tired - 20 mph easy pedaling, 25 if you work at it some.

If I ride the roads here the hills do me in. 10% grades are common, and I live at one of the highest points i the county. So I don't ride much - hence the desire for an electric leg.

****

SO what is a realistic range? Does using pas vs throttle extend it? How much? I see most controllers have 3 to 5 assist levels - does using a lower assist level (either going slower or pedaling some) extend range and by how much?

I know in a car 55-60mph will give you 10%, or more, improvement in mileage (range) than driving 70-75 (alas, the speed limit). Is there a point on bikes where you lose more range than you gain in speed?

My bike fits your description pretty well - It's a 750w/1000w peak geared rear hub motor with a 48A/20AH battery. The bike itself with battery weighs over 80lbs, and it has big fat tires (I keep them very highly inflated to reduce rolling resistance, but its still more effort than a regular bike tire). I've also got a couple panniers, a heavy kryptonite chain lock, an extra light, some supplies (patch kit, reflective clothing, a spare hoodie jacket, etc) to easily add another 15lbs or more to the mix.

I'm also a gigantic fatass. Like a person and a half minimum, or 2 fit people

My bike will take me about 30 miles at 20-25mph, which I consider pretty darn good since I put in relatively little effort. I'm very happy with this range! Note that the last bit will usually be a bit slower - as the capacity of these batteries gets drained their voltage starts to lower, and the motors lose a bit of power. I believe a smaller person would easily get 50 miles out of one of these, or more.

 

[tomjasz]

Thomas,
What type of connectors are used with the wattmeter? Would I need to cut existing wiring harness to patch it in? I think it would help me measure battery stats to help keep me in a lower pas setting.

Also, do I just run the battery down and then measure voltage to find the Low Voltage Cutout?
Thanks,
Ken

I'm sorry I'm a kit builder and support other kit builder customers. Kits have more exposed wiring and it's easy to splice in or use the battery connection on one side and add another connection on the controller.

 

[Captain Slow]

I've done two rides of 65 km's on my bike and I've had either 57% or 55% battery remaining. I'm comfortable saying I'd get over 100 km's on my battery.

 

[Lightning P38]

I'm sorry I'm a kit builder and support other kit builder customers. Kits have more exposed wiring and it's easy to splice in or use the battery connection on one side and add another connection on the controller.

For my next ebike, I am going to build a kit. Tell me about the kits you have, or a link to your web site.
Thanks.
Ken

 

[Lightning P38]

Lightning, my bet is, given more seat time, you'll eventually become a more efficient rider. I've always said there's a learning curve involved coming up to speed with an e-bike. There's more to it than a rookie is up for when he first sets out for sure! You need to balance PAS levels, correct gear, speeds, conditions, etc. Give yourself some time, relax a bit, and enjoy the bike for what it is for a bit. Then make whatever mods you think are necessary. -Al

I got in a 10 mile ride today. Really starting to get the feel of the ebike.

Got the battery gauge to move down to 66%. Battery was at 39 volts on my 36 volt system when I got home. Rode at pas 2 half the time and pas 4 on a busy road with a 25 mph speed limit. Cruising at 20 mph like I could 10 years ago pre-heart attack.

Don’t really need to use the throttle. Found I can pedal with one foot when starting out on my recumbent bike....it is different than riding a diamond frame...just a bit harder to get started on a bent, but you get used to it.

I found out my derailer is not shifting into 1st gear On the rear. It has 17,000 miles on it, so it may need to be replaced.

Nice day today. Will do it again tomorrow, as will be even warmer.

 

[indianajo]

I found out my derailer is not shifting into 1st gear On the rear. It has 17,000 miles on it, so it may need to be replaced.

There are two adjustments that can be tried first. The outer stop can be backed off. The cable slack can be removed or tightened up by either adjusting the screw on the shifter control, or by unbolting the cable clamp and moving it. I find vice grips useful for holding the cable still while I tighten the clamp nut.
I replace derailleurs when the tips of the little wheels get worn, or the little wheels start wiggling from side to side. That happened about 10000 miles on my 15 speed mountain bike. I've never worn out the arm pivots.

 

[harryS]

Thomas,
What type of connectors are used with the wattmeter? Would I need to cut existing wiring harness to patch it in? I think it would help me measure battery stats to help keep me in a lower pas setting.

Also, do I just run the battery down and then measure voltage to find the Low Voltage Cutout?
Thanks,
Ken

These wattmeters have no connections at all. Just bare wires. I use XT60 connectors between the battey and controller on our various (six+) ebikes, so I have the same connectors on the wattmeters. The one in Thomas' pic will store max current used, minimum voltage seen, plus total AH/WH. Unfortunately ,if run down to where the battery shuts off, you lose all that info unless you power it off a second battery (connector available).

You can also put it between the charge and battery and measure how many AH went back into the battery. I've found that the AH going back in compares to what was taken out.

Watt-hours on these meters taken during a ride is often flaky, so I only use the AH.

 

[harryS]

For my next ebike, I am going to build a kit. Tell me about the kits you have, or a link to your web site.
Thanks.
Ken

I thought this was a kit. I guess you bought the ebike all put together.

 

[Lightning P38]

I thought this was a kit. I guess you bought the ebike all put together.

Sorry for the confusion....I bought the ebikekit.com brand for my Lightning and installed it. It does not have any extra connections or ports, for such things as a speed sensor or a watt meter. Apparently some kits use a different controller, lcd display, and controller connections that allow more choices.

I did not have any choices with the retailer that sold me the kit from ebikekit.com, except the basic: wheel size, And number of gears on cassette, and a rack mount or frame mount battery. So it was take what you get, and hope you liked it. I do like it. I did have trouble getting the hub to fit into the rear stays. I made a wood brace to spread the dropouts, and reversed one of the tabbed washers on the axle, and then it fit.

A friend has some interest in adding a kit to her bike, and only wants to spend $600, so a lower priced kit might interest her. She may opt for a fully built ebike...depends on the $.

I am more interested in a 2nd kit that I can specify all the parameters. And I would like to install a 2nd kit, whether its for one of my bikes or someone elses. I have a trike, commuter bike, and two mountain bikes. And a few vintage bikes, but they wont get a kit.

 

[tomjasz]

$600 bucks for a kit AND battery? That's not going to be a reliable purchase.