Long Distance Ebike Design

jkbrigman

10 kW
Joined
Oct 27, 2011
Messages
794
Location
North Carolina, Southeast US
Wanted to start a discussion about a build of an ebike intended to be a long-distance machine, something you can do 100, 200 or even 300 miles on in a day, at an average rate of about 25 miles per hour. Example questions to discuss are:

- What drive system would you prefer? A hubmotor (DD or geared) or a mid-drive?
- What kind of battery and controller?
- How much battery capacity?
- What kind of onboard charger?
- What kind of load-carrying features? (rear rack? Panniers, Front Rack? Front Panniers? Trailer?)
- Would you take any solar panels?
- Would you install any fairings (front, rear, or anything else) on the bike?
- What kind of tires?
- Would other features provide any specific advantages, like the gates carbon drive or nuvinci hub?
 
Gonna need one of these guys but with even more battery

electric-bike-battery.jpg
 
And before I get too far, I'll lay my own cards on the table. My own conception of an optimized long-distance bike would look like this:

http://www.easyracers.com/goldrush.html

gold_rush.JPG

- LWB recumbent. No suspension.
- "Zzipper" front fairing.
- 25mph average, 30 mph "max cruise"
- Solar cells mounted on the front fairing? (that's really a question, not a comment)
- high-pressure schwalbe "Energizer" tires
- 250-400W geared hubmotor or mid-drive.
- About 1Kwh of onboard battery
- Onboard charger - as large as feasible
- Rear rack with panniers. Front and rear fenders.
- "center" or under-seat panniers intended for LWB recumbents

Looking to achieve 10Wh/mile average or less.

Going by simple numbers, that points to pack sizes of:
1) Minimum of 1000 Wh, 1200Wh to keep 20% reserve for 100 miles
2) 2400Wh for 200 miles
3) 3600Wh for 300 miles

I'm doubtful the 2) and 3) pack sizes are realistic for a bicycle - seems they might be too heavy.

This is a bike that could easily do an intra-state or regional ride, but has enough range and robustness to handle a RAMM-type ride from the Pacific to the Atlantic. A bike where, when you find yourself riding through Arizona, New Mexico and Texas, you could just ease on down the road but make 300 miles a day if you had to.

So: the question I'm putting to the E-S brain trust is: Anyone out there doing this right now and have any real world information to share?
 
300 miles a day? Pretty ambitious on a bicycle, even a recumbent, just the physicality of riding.

I remember just before I 'left' this forum for other interests, six years ago, Justin Le rode his E-bike across Canada, Coast To Coast. So there is a guy with 'real world experience'.
 
RLT said:
300 miles a day? Pretty ambitious on a bicycle, even a recumbent, just the physicality of riding.

I remember just before I 'left' this forum for other interests, six years ago, Justin Le rode his E-bike across Canada, Coast To Coast. So there is a guy with 'real world experience'.

RLT: You're right, 300 miles is extremely unusual. To me, it's just a number, but something I wanted to think out loud about. The holy grail for me is a "100 mile bike", which really means a 110-120 mile capable machine (you need a little overhead) down to 80% depth of discharge. To be perfectly honest with you, this is a future build I'm thinking about, so I'm trying to make some ideas and variables more concrete before I attempt this.

I don't think of a 100 mile ebike as anything unattainable or mystical: JennyB has documented 100 mile rides on her road bike in which she's using the electric propulsion as only a hill assist. That's a valid "use mode" and something I think is feasible if the bike is light enough (and you aren't carrying too much onboard cargo). If you start carrying 50 lbs or more, you start wanting electric help even on the flats.

And BTW: You are right, Justin has done it (VERY well!) and I have pored over every word in his thread. I'll hunt it back down and replace this sentence with a citation of his thread. I'm hoping, hoping, hoping that somewhere along the way on this thread, Justin will offer some comments!

Alan B said:
You might re-read Kingfish's threads, he's done a lot of this. He's gone toward 2wd with a trailer to carry a lot of batteries, but he's tried many things along the way.

Alan B: You are right, and thanks for the reminder, I'd forgotten Kingfish's threads. I'll edit this posting later and replace this sentence to cite his thread.
 
Yeah, if you're gonna carry a kiloton of battery and ride a recumbent, you'd better put the batts in a trailer (maybe even a streamlined one) so you don't explode the wheels. 'Bents are already super abusive on wheels because you can't use your legs to suspend your weight when you ride over bumps.

If you want to spend 12 hours in the saddle without pedaling much, I can see why a 'bent might be a good starting point, though.
 
Chalo said:
Yeah, if you're gonna carry a kiloton of battery and ride a recumbent, you'd better put the batts in a trailer (maybe even a streamlined one) so you don't explode the wheels. 'Bents are already super abusive on wheels because you can't use your legs to suspend your weight when you ride over bumps.

If you want to spend 12 hours in the saddle without pedaling much, I can see why a 'bent might be a good starting point, though.
3600W is only ~14kg (31pound) of Panasonic NCR18650B :D
 
Bring a test rig on over to RAGBRAI. The longest day is usually a 100 mile leg.
 
Chalo said:
Yeah, if you're gonna carry a kiloton of battery and ride a recumbent, you'd better put the batts in a trailer (maybe even a streamlined one) so you don't explode the wheels. 'Bents are already super abusive on wheels because you can't use your legs to suspend your weight when you ride over bumps.

If you want to spend 12 hours in the saddle without pedaling much, I can see why a 'bent might be a good starting point, though.

Chalo - I concur. When I converted my SWB to a rear 9c 2810 DD motor, I got flex and sway in spots I didn't even think it was possible. I think anything to do with a electrifying a recumbent needs to take a lesson from the velomobile guys. They tend to use smaller motors (250W-400W), smaller controllers and less onboard battery.

I mention a mid-drive in the beginning of this thread as a possible motor drive system, but I'm about 90% sold on a lightweight geared hubmotor on the rear. I may hate myself on a really long, steep climb for not going with mid-drive, but I expect you aren't going to want to ride 10-12 hours-ish if you have to listen to a mid-drive making a racket.

Thank you for the comment on why a 'bent might be a good starting point. Comfort plus efficiency are my overriding concerns. When I'd converted my SWB as my first build, 10Wh/m was easy to achieve, and at fairly high speeds between 23 and 30mph. I have no fairing on that bike either.
 
My go would be a full suspension leaning recumbent trike. (2 wheels in front)
I would build it rather heavy with a steel tube frame and possibly a motorbike swingarm in the back. A lot of batteries just above the ground closer to the front axle than to the rear wheel. For carrying load I would install two (big) bags on on each side of the rear wheel.
Add a front fairing and some plates to cover your frame properly you should be able to get good efficency.

-Mid drive probably something like the big block gng
- LifePo battery capable of 5 kw bursts, Sinewave controller (sabvoton?!)
- about 3000 WH
- Justins new all chemistry charger
- 2 rear racks/bags
- No too much hassle
- front fairings and enclosure for frame and battery and probably wheels
- motorcycle tyre in the back somthing like 20" hookworms in the front
- Schlumpf drive at the cranks in front keep the rest as simple as possible
 
gogo said:
Bring a test rig on over to RAGBRAI. The longest day is usually a 100 mile leg.

That's a superb suggestion. I've always been a fan of RAGBRAI even though I've never participated (I'm in the US southeast and have never traveled that far for a ride...but I want to)....
How would they feel about an ebike? Do they care?
 
sigimem said:
My go would be a full suspension leaning recumbent trike. (2 wheels in front)
I would build it rather heavy with a steel tube frame and possibly a motorbike swingarm in the back. A lot of batteries just above the ground closer to the front axle than to the rear wheel. For carrying load I would install two (big) bags on on each side of the rear wheel.
Add a front fairing and some plates to cover your frame properly you should be able to get good efficency.

-Mid drive probably something like the big block gng
- LifePo battery capable of 5 kw bursts, Sinewave controller (sabvoton?!)
- about 3000 WH
- Justins new all chemistry charger
- 2 rear racks/bags
- No too much hassle
- front fairings and enclosure for frame and battery and probably wheels
- motorcycle tyre in the back somthing like 20" hookworms in the front
- Schlumpf drive at the cranks in front keep the rest as simple as possible

Hey sigimem - Is this your dreamy holy grail three-wheeled motorcycle and you just wanted to get the idea down on the screen? This stopped being a bicycle by the third sentence....

JKB
 
Yeah, 100 - 120 miles seems fairly easily do-able with a home-built if you can spend the money and the roads are relatively flat.

That was (and still is, now that I'm back in the game) one of my goals...Or at least 60 miles, with 30 miles of steep and rough uphill in the middle. Except I want to do it on a mountain bike, and without much pedaling.

I'll be following this thread with interest.

.
 
jkbrigman said:
gogo said:
Bring a test rig on over to RAGBRAI. The longest day is usually a 100 mile leg.

That's a superb suggestion. I've always been a fan of RAGBRAI even though I've never participated (I'm in the US southeast and have never traveled that far for a ride...but I want to)....
How would they feel about an ebike? Do they care?
I think the average age of riders is 45, so you would be an ambassador for ebiking to an audience that will soon need assistance if they don't already. Although there will always be 'purists', I'd think there would be plenty of people who, even if they weren't interested for themselves, know somebody they want along that would need assistance.

One of my goals is to be the first to ride RAGBRAI without a single pedal stroke. This would demonstrate the potential for any level of assist, including 100% for those people who can't propel themselves. When I worked for a few decennial census operations I was amazed at the number of physically otherwise-able people in any given neighborhood. They are everywhere, and they need to know that they can participate, too!
 
skeetab5780 said:
Gonna need one of these guys but with even more battery

electric-bike-battery.jpg


That is bloody brilliant! I Love it!!
 
Hey sigimem - Is this your dreamy holy grail three-wheeled motorcycle and you just wanted to get the idea down on the screen? This stopped being a bicycle by the third sentence....

Yeah thought about that too I don´t want to mess up your thread. However to me handling is important because of that I suggested this vehicle which should not be affected by the additional weight of battery and cargo too much and can have low aero drag. Plus I don´t think a electric bike capable of more than 100 miles will fit my expectation of bike design. IMO its not as soon as you put a trailer on it so :?
 
jkbrigman said:
- What drive system would you prefer? A hubmotor (DD or geared) or a mid-drive?
Doesn't matter
- What kind of battery and controller?
Only the battery matters
- How much battery capacity?
My rule of thumb for a 36V, 20A, 500Watt motor is about 1ah per mile, average, hills included. For a 100 mile trek, you'd need 100 ah. Considering same draw.
- What kind of onboard charger?
Get a good charger. Make it "on-board" by carrying it with you.
- What kind of load-carrying features? (rear rack? Panniers, Front Rack? Front Panniers? Trailer?)
Enough to carry the gear you'll have. Go light - don't take anything you don't need, period. Water, yes. Food, no - you can buy it on the way. Design for a "cargo" bike - lot's of ways to do that.
- Would you take any solar panels?
No. More weight and nuisance. Electrical outlets are everywhere, just ask. Take a kilowatt meter so you can pay for your charge. Gas stations are usually OK with the idea. So are restaraunts, coffee shops, etc. Starbucks ++1,
- Would you install any fairings (front, rear, or anything else) on the bike?
No.
- What kind of tires?
Best money can buy. Same with the tubes. Or go tubeless.
- Would other features provide any specific advantages, like the gates carbon drive or nuvinci hub?
Really good spokes and rims too. Rims, spokes, tires & tubes take all the abuse. With weight, you'll want to look into shock absorbers on the drop downs..
 
In the MegaMonster Enduro rides they constrain the eBikes to 2KWH which is sufficient for (at least some) bicycles to cover the hilly 100 mile course. That's been my plan for the eBikeE, when I get around to finishing it. :)

For that I chose a geared rear hubmotor, which displaced the three speed rear hub, leaving the single front chainring and set of 6-7 rear cogs.

Note that this ride also requires human powered capability of 18 mph for one second, so it has to be possible to pedal it that fast for a brief time. :)

http://megamonster.lowkeyhillclimbs.com/2014/
 
100, 200 or even 300 miles on in a day- i think this is possible- but at that 25mph rate that would entail a really heavy battery
if youR terrain is easy and provided that you have place to charge up.... with a cargo bike you should be able to handle it.
theoretically lets take 300 miles as an example- 480km - say you were to ride 20 mph- that's 15 hrs on the saddle + give 6-9hrs in total for re-charging - re-charge every 100 miles(lets say 2-3hrs)- lets assume 15wh/km(20mph speed) 20wh/km for the 25mph - say you got a 48v battery and a reasonable course than - 480 * 15wh/km / 52v= 138ah Yikes is required. && 184ah if you running your 25mph :) say you got a 60ah 48v (70lbs limn or 44lbs of lipo) ..cargo bike could easily handle the 70lbs... and a real fast charger ... run a 24 day with no sleep , only stopping to recharge, you might be able to do it... if there are mountains in the way you will over-consume causing a small set back,
and keep in mind this assumes you have places to charge up when you run out && fair terrain(no mountains in the way).... i would be most comfortable with 100- 200 would be a bit too long for me
 
Alan B said:
In the MegaMonster Enduro rides they constrain the eBikes to 2KWH which is sufficient for (at least some) bicycles to cover the hilly 100 mile course....
Which is about 55 ah at 36 volts. So you'd need to be peddling a lot. Say you're carrying 80 lbs of gear too. I'll stick to my 100ah estimate. But don't use math - when you've got a fully assembled and gear loaded bike, take it on the road to get actuals and then use that to revise how much battery you'll need.
davec said:
... and a real fast charger ... run a 24 day with no sleep , rest or stop, you might be able to do it...
again, the batteries are everything. No, its not the charger that makes for a fast charge, but fast batteries. The A123 nanophosphate cells, for instance, can easily handle 30C on charge & discharge. Yea, a 48 volt, 60ah A123 battery would do it. Stop for lunch & dinner and charge while at your eatery. You'd easily do 100 miles in a four hour stretch. 3 stretches a day, you've got your 300 miles. About a hour & a half for the charge, by my estimate. 2 hours to be on the safe side. So ride 4 hours, 2 hour eat, rest & charge - that's about 16 hours. Sleep for 7, get up & repeat.
 
Stay away from hills and headwinds. On the ride across Iowa map, notice that it crosses the flattest part of the state in the direction of the prevailing winds. I would begin with a solar inspired flattened tear drop body on a tadpole trike using the lightest high speed drive system and electrical components and a very large sum of grant money in the bank. 8) Solar assisted from Palm Springs to Phoenix with no AC, on second thought...... :oops:
 
arkmundi said:
again, the batteries are everything. No, its not the charger that makes for a fast charge, but fast batteries. The A123 nanophosphate cells, for instance, can easily handle 30C on charge & discharge. Yea, a 48 volt, 60ah A123 battery would do it. Stop for lunch & dinner and charge while at your eatery. You'd easily do 100 miles in a four hour stretch. 3 stretches a day, you've got your 300 miles. About a hour & a half for the charge, by my estimate. 2 hours to be on the safe side. So ride 4 hours, 2 hour eat, rest & charge - that's about 16 hours. Sleep for 7, get up & repeat..

i agree and that would work- most on here have used lipo for their long journeys because it's super light- those amp20 are light also and safer.... as an example "ZIPPY Compact 5000mAh 7S 25C Lipo Pack" weighs 865 grams. 2 sticks give you the 48v you need- * 12 to give you the 60ah(good for about 130miles) -that's 24 sticks * 865g .. 45lbs ... with the amp's its about 50lbs...and both can be charged quickly so you don't waste time..... and if you do 90 lbs of the stuff.. you'd get really far without having to charge much at all....

regarding the charger even though the battery can easily handle high amp charges- with most outlets you are limited to 1kw
so you'll only be able to charge at 20amps..... 3hrs to refuel the whole 60ah...there aren't that many outlets that can handle 2kw without blowing a fuse
 
jkbrigman said:
I don't think of a 100 mile ebike as anything unattainable or mystical: JennyB has documented 100 mile rides on her road bike in which she's using the electric propulsion as only a hill assist. That's a valid "use mode" and something I think is feasible if the bike is light enough (and you aren't carrying too much onboard cargo). If you start carrying 50 lbs or more, you start wanting electric help even on the flats.

Yes, I think what I have got now is a good fit for an upright bike. With a 36v 20amp battery I can now go for any 100 mile road ride I would actually want to ride and not worry about recharging, and all with less than 8 kg more weight than a bare bike. With a fast charger I can recharge whenever I stop to eat, and not be waiting around when I want to go again. I can even recharge in the evening and ride right through till dawn. I have done more than 230 miles in under 24 hours. (Report here)

I can't manage 300 miles in a day, though, because I'm too slow: my rolling average is around 15 mph. Still, after doing two rides of more than 200 miles, I don't particularly want to. I think, when you are riding for pleasure as opposed to a challenge, 200 km (126) miles in a day is plenty. Indeed, it's plenty even on a motorbike or in a car! Still, a faster rolling speed does allow you more time away from the bike.

For me, and for many people, 20 mph average is where a normal bike starts turning into a moped. I can manage 20 mph average on full throttle for an hour or so if I am in a hurry, but beyond that it just takes too much concentration. Past 25 my pedalling probably doesn't contribute much anyway; I'd be better of getting as aero as possible and letting the motor and gravity do the work. Recumbents don't have that problem, in particular long-wheelbase recumbents with front fairings and nice stable handling. For a bike like that 25 mph should be no problem to hold with about 300 watts of assistance. That works out at about 12 watt hours per mile. For 100 mile range 2kwh should be plenty, accepting that you won't get anywhere near the same average speed on the big hills. Bill Bushnell rides bikes quite similar to what you are thinking of, capable of cruising economically at 25 mph, and as you can see here his average rolling speed in the California mountains is 18 mph or less. Those hill are BIG. :mrgreen:

Finally, I used a pair of charger on my long rides that charged at 432 watts. The fans are a bit noisy, and I wouldn't like to have to share, and probably the most practical all-round solution would be a couple of Satiators or Solid-state LED drivers outputting 720 watts. A fit touring cyclist can output 800 watt hours on a hard day, a world class racer perhaps 2 kw hours. The equivalent batteries could weigh less than 4kg and 10kg respectively, and take just over an hour or just under three hours more charging time for an electric-only bike than for one with a hard-working rider. :twisted:
 
Some thoughts for you from the top down: :)

Distance = Velocity x Time. No going around it. 300 miles in one day is at best well beyond the scope of a bicycle, and most definitely in the realm of ICE Motorcycle given present-day off-the-shelf tech.

Recharging: If you are doing a one-off 300 mile dash, then you might be able to sacrifice your body to slog it out at whatever velocity you could fathom. But that’s not the type of riding I would consider normal or repeatable day after day.

For myself, I found that after 5 hours in the saddle my bum began to ache, and 7 hours was about all I could stand. The 2nd half of my 2011 road trip to California displays where I finally found a rhythm of eating/sleeping/recharging when The Day begins at 4AM, prep the bike and get on the road at the crack of dawn with the idea that I’ll beat the headwinds (which always appeared between Noon and 2 PM) just as I’m approaching the destination. That left me with the afternoon to get settled into a room, get my shower, beat all of that afternoon heat, and still have time for a beer after dinner. Then hit the sack by 8 or 9 PM, charger going all through the night. Get up at 4AM and do it all over again.

The terrain will dictate your velocity as much as weather. Level ground will yield higher speed and greater distance. Probably the easiest day was the one between Bend Oregon and Klamath Falls; fairly straight route with a small amount of elevation change. The theoretical distance of the system was 220 miles, but the farthest that I managed on a single charge was about 167 miles between San Raphael and Fort Bragg California and took about 7 hours at a slow 24 mph – mainly due to headwind. It was hilly, twisty, foggy, winding, and at times fraught with nasty drivers in gilded Lexus SUVs.

So before you head off and ask for a design that can take you 200 or 300 miles… on a bicycle… know that what you are asking is quite beyond what most humans can do solo.

Now we can talk about equipment:

Weight is your enemy. Suspension is your friend. Solid framework & construction & reliability is essential. :wink:

The most reasonable-cost battery having the highest energy-density is LiPo, with the best configurations hovering around 5 to 6 cells at 5 to 6 Ah per brick. Given the amount of battery required for a long distance journey - you need not bother with High-C capacity; it’s a waste of money. Instead, increase the size of the main battery wiring harness – and the math says that switching to Aluminum is both less expensive + less weight, even though the AWG will need to be 2 less (meaning a larger diameter) for the same ampicity. On the capacity: I was averaging about 50 Wh/mile. This number will reduce for short distances, and increase for longer mainly due to system drag caused by battery weight. Do a few Centuries to get an idea about your consumption. Know that there is a limit to battery capacity; that there comes a point when adding more battery will work against you.

One motor or two? One motor is more efficient on a flat, no question about it. When it comes to hill-climbing, arguably it’s a toss because the application is no longer equally comparable: There’s a whole thread on this where both sides have flogged the horse into burgers and sausage. The one thing that can be said in unequivocal favor of 2WD is that of redundancy: Unless you have a sag wagon, or you carry your tools with you, redundancy has an infinitely better chance of getting you to safe harbor over none at all, and the energy investment is about 10-15%.

Aerodynamics is a must. This means analyzing the riding profile, drag of baggage, and body faring. Less drag directly equates to speed and distance. It doesn’t need to cost a lot of money or weigh very much either. I found my faring increased the top-end by as much as 20%, and was a game changer when facing headwinds. MtBs have the worst posture, although the best visibility; recumbents are at the other end, and likely better on the body for long endurance. The 3-wheeled versions appeal to me, though may be challenging when sharing the road.

What else can I suggest? Make sure your EV can be secured each night; I brought mine into the room for recharging. The charger must have enough capacity to recharge your system in less than ½ day and not pull more than 14 Amps; most wall sockets are rated at 15A, however the bathroom of most motels are rated at 20A. My charger pulled about 1 kW – and even then I popped breakers in the older motels; pretty scary site when you see a whole bunch of plugs all ganged up into a single outlet… can’t watch TV and run the Microwave at the same time, let alone charge! The sacrifices we make… :lol:

Forget solar: If you’re going to use that as a supplemental power source then plan on parking for several days. ‘nuff said. :p

Last words and tips: Get off the bike every 20 miles and walk around, stretch, water-up, eat something, smell the roses, even if it’s just for 10 minutes. Watch the weather and check for road construction; plan for alternative routes. Carry a phone; let your friends/family know where you’ll be, and check in twice a day for safety and their peace of mind. Don’t where headphones. Bring sunscreen, no… sunblock! Watch your back; 99.99% of the people on this planet are cool, but selfish assholes exist if only to ruin your fun and I met at least one every day. Finally, have fun, take pics, and share!

Best o’ luck to you, and to others that are considering the same. 8)
Safe travels, KF
 
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