hypothetical range question..

lol so... would there be loud objections if i said i was thinking of a ping battery?
 
muffinman said:
lol so... would there be loud objections if i said i was thinking of a ping battery?

Tell me.

What kind of bike you're using.
What kind of ping battery you're going to get. (How many watthours)
What average speed you're thinking of.

On an upright, I'd be sketchy of a 1kwh battery for 30 mph, but 2kwh would probably be fine. Main concern would be how the battery will age after 2 years since the ping's c-rating cuts in half in older age.
 
swbluto said:
What kind of bike you're using.
What kind of ping battery you're going to get. (How many watthours)
What average speed you're thinking of.
cannondale m500
either 48v 30ah or two 48v 15ah (to balance weight in panniers if the big one wont fit in the triangle).
30kph average, 35kph max
this is all just guesswork on my part, i dont have a clue what i would actually need.
 
swbluto said:

Yes! Tell me your location lol over 5,000 posts..... lol I take it the picture means the UK?

Tommy "Sherlock" L sends..... :)
 
muffinman said:
swbluto said:
What kind of bike you're using.
What kind of ping battery you're going to get. (How many watthours)
What average speed you're thinking of.
cannondale m500
either 48v 30ah or two 48v 15ah (to balance weight in panniers if the big one wont fit in the triangle).
30kph average, 35kph max
this is all just guesswork on my part, i dont have a clue what i would actually need.

The 30 amp hour Ping won't fit in the triangle even one of the 15 amp hour probably won't either. The rectangular shape makes it difficult. If you get 1.5 KW hours (the 30 amp/hr battery) you should have no problems with the C rate going at 35kph. That's a lot of weight though on the rear carrier. You will need a very substantial carrier rated for that weight.

You will definitely have the range with a good reserve but the handling may be compromised especially assuming you will probably go with a rear wheel hub motor. On the plus side if you purchase a frame bag too you will have somewhere to carry some stuff.

Get good wide tyres preferable kevlar lined and hopefully you won't get any flats. I have yet to get a puncture in over 5,500 kms of cycling with Schwable Big Apples. My trailer though with ordinary Kenda tyres has had two in the same period with one completely destroying the tube.
 
Start with one 48v 15 ah ping. It will fit in larger triangles. Make a box the size of one, and see if it goes in your bike.

Two would carry in panniers, and get you the 60 mile range at 18-20 mph for sure. 1.5 kwh of capacity.

One good reliable ping will get your local transportation needs covered, and will work fine with up to 25 amps controllers, and will be easy to carry. A 20 ah will suck to carry at all times. It should last 3 years of daily use, possibly more.

Adding range later with more battery, you could try a cheaper vendor than ping, for a battery used less than everyday. It could be completely different, even a different voltage. You'd be able to ride one, then the other if too different to parallel them to ride. You won't need 48v to go 18 mph. So it could be a 36v 20 ah, 44v 20 ah, whatever works for the budget at the moment.
 
Re reading, if you have the cash, two pings is fine, but you just don't want to carry 30 ah all the time is my point. One will get you 25-30 mph travel around town, for twenty miles or so. (40kph for 30 k)

Carrying two pings, two 5 amp chargers gives you 500wh in a 45 min break if you have a place to charge halfway. That could allow riding much faster on 1.8kwh of available power. You'll have to carry at least one charger anyway, or have one stashed at her house.
 
Wooh! I don't feel like such a wierdo now, suggesting "low-end" power of 750 watts or so... N obviously having both time and energy are important factors...

muffinman, dude, if yer happy round the low to mid 30kph, I reckon if you can remain road oriented, then small geared hubmotor is the go.

Here are some pics of my main GoTo bike, many trips of 40km (yeah I know, I know, that's not 100 km.. just sayiin... range on this for me is 60km)

At 47 and carrying injuries from a physically risky past :)D) I am not that fit , nor young and my weight varies from 80 to 100kg with varying density.

I aim for around 30 to 32 km/hr when peddling... my average over the last 300 km has been 22... but that is a lot of urban and suburban street riding.

More human input is eminantly doable, and the fact that the hubmotor free wheels is really noticable on descents.

I am using relatively high pressure (50PSI cyclo cross tyres... kinda like an offroad tyre for road bikes :D) with fairly low rolling resistance, and this bike is built for roadwork.

Some Pics
Drive side full view.gif

Drive side Full View

MiniGiearedHubMoter.gif

Mini Geared HubMotor


BatteryAndController.gif

Battery and controller... Battery mount is an inverted seatpost rack that fits around the seat tube... easy on chromolly vintage... not so easy on modern larger seat tubes.

Cockpit.gif
Original gears for this age bike would have been either on the stem or downtube. Although stiff, these cheapo shifters work.

Th throttle has had the standard battery level light and on off switch cut off to clear the shifters.



GearedVersusDD.gif
As luck would have it I hade a dd 250-1.2kw rea drive nearby laced in a 26" rim, giving good size comparison

HybridDriveChain.gif

Human and Electric drive chain :D








This build uses a 250w/36v rated no-name brand/Cohnis geared mini hub motor laced into a 700c rim.
The controller is a 10ah controller purty much the same as yescomusa sells, modified from 20 amps to 10 amps
The battery is a nominal 48v 10ah Lipo Pack (4* 6s 5ah in a 12s2p configuration for 12s 10ah)

Max wattage for this motor in this configuration is around 700 watts
Max speed on the flat in ideal (no headwind, smooth surface) conditions is around 35km/h

The base bike is a vintage (early 80s) Crome Molly steel road racer.

all the parts/componets I reckon you could source for $500 (cheaper if you are willing to do your own bike building and source of craigslist or woteva and probably cheaper in US dollars (I am thinking in AUS$))
NOTE: I have a cycle analyst mounted but it is not necessary,, a $20 wattsup meter and a 10 dollar cycle computer/speedometer provides all the data you need for day to day running.

I reckon 15ah, better yet 20 ah battery capacity would be the go... Not impossible that you only NEED 15ah if you truly are going to be grinding it out on the pedals.

Personally I don't think you can go past Lipo for cheapness and size, and srsly if you look after it, nothing beats it in my opinion...

15ah at 12s costs about 300 AUD, plus another $100 for charger and power supply and a meter...

For US1000 dollars I reckon you could get yourself something that could do the job...

Opinions may vary :D and this is just an example of what you can do with lighter builds that can work if you want cyclist speed assist.

Joe
 

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ok. this hypothetical was to try and determine how difficult it would be to make one ebike that could have its range extended temporarily. im planning to build a bike with about 20km range (motor alone) for getting to and from university in the summer, when the bus schedule is crap.
the bike (current plans): cannondale m500 (owned), a 9c motor kit from grin cyclery (not owned, but want to support them), battery sourcing is to be determined, but was thinking 48v 10-15ah, depending on what i can fit in the triangle.
from that set up, i was thinking of having a second battery to add to it to make it capable of 100km with considerable pedal input. i can ride for at least 2 hours at about 20kmh average. hills are still murder, but i can force myself up them. for the long distance trip, an average of 30kmh, with a max of 35kmh, is fine. im ok with a 3ish hour trip.
if it matters to aiding suggestions, im 6ft tall, 220lb ish, 24 years old, ride 10km daily minimum, and ride as long as the weather is ok (havent got into winter riding... yet)
 
For sure MuffinMan... sounds like your plans are good uns.

If your going for a 9c, and ONLY looking for the mid 30's kph, I am pretty sure, depending on the windings you choose for the 9c, that you can get a 1:1 ratio volts to top speed, meaning you only really NEED 36v.

This gives you more options in form factor and prolly a 25% reduction in cost of battery.

15ah in the triangle, solid rack for a secondary battery of 15ah for your Long Distance runs.

Very simple solution to swapping batterries is to have a long enough power lead from controller to batttery connection to either hook up to in-triangle or to rack mounted. Just manually disconnect/connect when one battery is running low.


As you know if you choose two identical batteries for primary and secondary when doing the uni commute, you can keep one charged at home, and should be able to get 40km with one 15ah and your legs, meaning You constantly have one battery fresh and ready to swap in at home.

Joe
 
Oh and another thing... Stuff you already know I am sure but worth repeating, methinks


How you ride your e-bike can make a huge difference to your range.

I personally found Fart arseing about in an urban environment, making the daily commute fun with an electric bike and ploughing through the juice... re-charge at work, and do it all again on the commute back home was great. Freakin' Awesome Actually :D

Then, when going on longer rides, more conservative on the throttle... sucking in watts via regen at every opportunity (if you go for regen) and all that stuff and you can increase the efficiency of your riding many times over... same as when yer driving an ICE vehicle with intent on maximising range versus drag racing at every traffic light :D

Joe
 
lol 48v was because i do like to go fast... and better to have the speed and not need it than need it and not have it... and as we all know, you always NEED more speed!
 
Hmm... Going for speed? Forget all the previous estimates. They were based on 30kph and you doing real pedaling.

The energy needed will at least triple to 1,500Whr at 40kph and NO pedaling for 90kms. Good luck carrying that much low-density LiFePO4 battery.
 
SamTexas said:
Hmm... Going for speed? Forget all the previous estimates. They were based on 30kph and you doing real pedaling.

The energy needed will at least triple to 1,500Whr at 40kph and NO pedaling for 90kms. Good luck carrying that much low-density LiFePO4 battery.

Indeed. Want speed and long distance? Get a gasoline moped. Electric bikes aren't really designed for that unless you're willing to pay a lot, not at the current battery price levels.

Wait... I should do the calculations...

40 kph = 25 mph

25 mph = 25 wh/mi (I think? Haven't ridden an upright bike in a long time...)
1500wh/25wh/mi = 60 miles
60 miles = 96 kms

Ok, sounds about right. 1750wh of lipo would cost around $700 at Hobby-City's prices. Keep the lipo between 4.1 volts and 3.7 volts and it'll last for a pretty long time. Also, if one pack goes bad, it's lot easier to get rid of the offending unit than when one cell in a ping battery goes bad. I know, it's happened to me. (None of my lipo has 'gone bad' however, not yet.)
 
to clarify: for the long distance trip, 30kmh is fine. but for around town, where i can get home easily under my own power, more speed would be fun.
 
muffinman said:
to clarify: for the long distance trip, 30kmh is fine. but for around town, where i can get home easily under my own power, more speed would be fun.

That's how I operate. :mrgreen:

I'll do the calcs, be right back. (Using the simulator in my sig)

Looks like 1kwh at 30 kph would propel you about 63 miles or 101 km. (48v, 20ah LiFePO4)

1kwh at 40 kph is 43 miles or 69 km.

1kwh at 50 kph is 30 miles or 50 km.

If you pedal along, you can easily double or triple the range at 30 kph, depending on how much you want to work. Pedaling becomes less significant at higher speeds because of the sheer amount of power necessary to plow through the air and the piddling amount of power non-Lance-Armstrong types, like myself, can contribute.
 
swbluto said:
Looks like 1kwh at 30 kph would propel you about 63 miles or 101 km. (48v, 20ah LiFePO4)

If you pedal along, you can easily double or triple that, depending on how much you want to work.
Double, yes. Triple, no way, not at 30kph. The OP strength (according to him) is 20kph for at least 2 hrs. Meaning that he can only contribute up to 150W.
 
SamTexas said:
swbluto said:
Looks like 1kwh at 30 kph would propel you about 63 miles or 101 km. (48v, 20ah LiFePO4)

If you pedal along, you can easily double or triple that, depending on how much you want to work.
Double, yes. Triple, no way, not at 30kph. The OP strength (according to him) is 20kph for at least 2 hrs. Meaning that he can only contribute up to 150W.

30 kph is only 18 mph. My grandma can pedal that fast. :|

But, yeah, I suppose if he's the 12 mph kind of biker (20kph), I suppose tripling seems a bit unrealistic. I'd imagine with practice, though, he could easily sustain at least 15 mph by himself.
 
swbluto said:
30 kph is only 18 mph. My grandma can pedal that fast. :|
That's what everybody says. Most of them can't even do 14mph for 2 hours and that includes young people. Grandma would be lucky if she can finish 10 miles, regardless of hours.
 
SamTexas said:
swbluto said:
30 kph is only 18 mph. My grandma can pedal that fast. :|
That's what everybody says. Most of them can't even do 14mph for 2 hours and that includes young people. Grandma would be lucky if she can finish 10 miles, regardless of hours.

If he does a lot of long distance trips, I'd imagine he'd develop the stamina to do 15 mph continuous under his own power, thus capable of tripling distance at 30 kph.
 
SamTexas said:
swbluto said:
If he does a lot of long distance trips, I'd imagine he'd develop the stamina to do 15 mph continuous under his own power, thus capable of tripling distance at 30 kph.

If he doesn't, oh well.

2176156682_b2f92f82e0.jpg
 
Lotta difference how much your pedaling helps as speed increases. Even old farts in reasonable shape can provide half of a 200w total. But get into cruising at 1000w, and now your 100w of pedaling is only 10% rather than 50%.

For sure, if he's going as slow as 30 kph a young and fit guy can double the range he'd have gotten at 45 kph. As much as 30% of that increase from pedaling, the rest from lower drag. Even better if the guy can put out 200w for three hours.

This is developing into a very workable plan IMO. Two pings, or whatever. One in the triangle, one carried otherwise when needed for the long trip. He'll have a 45 kph ride in town, assuming a 9c 2807. But it will still ride slow with great efficiency at sub 30 kph.

Get a wattmeter, a CA if possible. You will really need a gas gauge to know at the half way point, whether you are going too fast or too slow. You can just watch your wh/mi on a CA, and know if you are meeting the target at any moment.

The trick is, set a speed, then pedal up 2 mph more. You'll see the watts drop at least 100w on the meter.
 
Here's another "Real World" ride from my ride yesterday.

Using a BIONX (which is efficient system) It's pulses on your in-between 180 degree strokes, on my Catrike 700
(a three wheeled recumbent).....
I used 9 watt hours per km and that was with me giving her hard averaging 30-40kph. Very windy on the return
portion. You will need a 1kw pack using 100% dod (depth of discharge) to travel 100kms. It was cooler yesterday
and I was riding in 18C. When doing this same trip at 28C I use approx. 7 watt hours per km (air density)

On an upright bicycle you will use more energy.

If your heart is set on electric for this distance and you don't want to spend money on insurance, then
consider purchasing an electric scooter and put some lithium in it. The scooter should be able to handle
the weight of your battery pack. Jam 2kw in there :) Your BUTT will be more happy
travelling for 3 hours :) When ever you can spread your weight per square inch over a larger surface,
the distances trips are more bearable. Yes, you can pedal, but not likely on those scooters. Ypedal would say:
"why pedal" lol :)

You can Hot Rod the Scooter, but wear a Pink jacket and helmet and no one will notice
that you are going faster than 32km ;) Just kidding! :)

Tommy L sends.....
mosh.gif
 
so, the general consensus is that 1-1.5kw at 30kph (over and above the reserve) seems reasonable, with a fair amount of pedal input?
 
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