Getting an electric road bike

cwah

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Joined
Jul 24, 2011
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Between paris and london
Hello all,

My previous BPM has died and now I'm without any decent way to travel now. I feel handicapped :(

I'm thinking to get a spare electric fast road bike I could easily carry with me. And that could also work when electronic fail...


I want to have something like the BH neo road bike lines:
[youtube]c39gSdRLRC4[/youtube]

Kepler did something similar with a SWX motor overvolted to 80V:
http://endless-sphere.com/forums/viewtopic.php?f=6&t=47139


I'd like to do the same thing. Get a super light/stiff road bike. Add a small motor. Get the motor to help a bit + pedaling.

After all, cyclists in Tour de France only average around 350W to do 25mph average. Can't we replicate that with a motor? Low power, high efficience?




Here's the bike I'm thinking to get:
specialized-sirrus-sport-2013-hybrid-bike.jpg

http://www.evanscycles.com/products/specialized/sirrus-sport-2013-hybrid-bike-ec042533#answers

It has good reviews and seems quite efficient for road bike.



Now, I need a motor. Which one would be best for a road bike at 25-30mph?
- A Cute100 260rpm?? I fear it may not be strong enough
- Bafang BBS02? benefits would be to have perfect freewheeling. Because geared motor still have a bit of friction...
- Xionga motor?


Any suggestion?

Thanks
 
I would recommend either an amped bikes or ebikekit rear geared motor kit w/ 36 volt lithium battery. Easy to install and light weight.
 
Can you explain why these kits are better than the motors I suggested?

- The cute100H is good mainly because it's cheap and easy to replace/fix
- The BBS02 has the benefit to being a crank drive so perfect freewheel compared to geared motors
- The Xionga motor is a dual geared motor that manage torque at low speed and high speed.

What about amped bike or ebikekit geared motor? Why these one compared to the ones suggested?
 
yes fast.

Why ebikekit motors would allow me to go faster than the other motors...? don't forget it's a road bike where I pedal so weight and DD are out of questions
 
I'd get a 48v 1000w gearless hub motor. My ebike has one and the friction is almost null. You can reduce the weight on the battery... Tell us your expectations about range, so you can look for weight better. My battery is 48v 20ah lifepo4 and its probably around 10kg (not sure). You can always go for a little bit heavier and use the motor only as an assist to suit your needs, I don't see weight as a problem, but I never pedal the bike, since I have big range (35km).
 
mateusleo said:
I'd get a 48v 1000w gearless hub motor. My ebike has one and the friction is almost null. You can reduce the weight on the battery... Tell us your expectations about range, so you can look for weight better. My battery is 48v 20ah lifepo4 and its probably around 10kg (not sure). You can always go for a little bit heavier and use the motor only as an assist to suit your needs, I don't see weight as a problem, but I never pedal the bike, since I have big range (35km).

my goal is to have a bike I can pedal when motor is NOT working. Like now I have a dead bike of 35kg because the motor died and I can't do anything about it.

So I'm not going to get a big DD or big battery on it. I'd also be able to exercise a bit on it!
 
No, no more Mac for me. I had an upgraded one, but it failed. It was the first to fail by the way. Customer support was the same as chinese sellers and the motor is still not repaired:
http://endless-sphere.com/forums/viewtopic.php?f=2&t=53821&start=50
 
updated my original post to show what I'm trying to get: light and fast, like the guys in tour de france!!

In tour de France, the guys only do 350W power in average. But reach 25mph. Why can't we do the same???
 
cwah said:
updated my original post to show what I'm trying to get: light and fast, like the guys in tour de france!!

In tour de France, the guys only do 350W power in average. But reach 25mph. Why can't we do the same???

Who says you can't?

The weight is against you, but most low power ebikes are restricted speed/power due to country specific laws. If you're building your own unrestricted bike why would you choose a low power one when you can get more power or the same (or similar) money?

do you really need such big, bold AND red type? It comes across as angry shouting- calm down?
 
All you need is a 150 person peloton to ride in. That guy in front, he aint pulling 350w. That's why it's so impressive when a guy pulls a long turn up there.

Nor are they riding stop and go, in real traffic.

Then, you have to consider that at least 20% of your electric 350w has vanished into heat. The TDF rider is measuring the wattage at the bb, after his heat has been subtracted.

What you want will work with 600w though, that we know. So you need a motor that can handle stop and go, the heat that will make. Not ideal for a fast rpm small motor. I'd say the bb motor might have a chance, but you will have to shift it a lot at the stops.

Dare I suggest you get another Mac, and run it at a sensible wattage? Nah.

And we also know, you will beat it hard, harder perhaps than I do beat stuff. So we are dying to see how the bb2 would hold up to that. :twisted:
 
sorry for the big and bold. I do that because I feel that people doesn't read properly and don't see my point.

What I mean is "less is more". Like any design, it's always easier to add more. More battery, more controller power, more motor power... and then we end up with bicycle than can't be pedaled at all.

I have a bigger motor (BPM), big battery (72V20AH), 80V35 controller on my previous ebike:
2014-03-16%2013.32.17.jpg


When it works fine, I'm faster than any normal rider.


But when it doesn't (my motor failed), even a small girl with a decent bike will go faster than me....



So what I want now, is to have an ebike that drives like a bike. And that the motor support my pedaling without being a hurdle. See kepler super commuter bike to see what I mean:
http://www.endless-sphere.com/forums/viewtopic.php?f=6&t=47139&hilit=super+commuter
 
I was looking at that bike the other day. But I don't know if that was used in quite as urban an environment.

For sure, if you break down, a full sized bike with good fit for your body will be easier to pedal. But not so easy, if you load up with a ton of battery to go FAST.

You can definitely make a nimble easier to pedal bike with a small motor, if the commute is not too long and punishing. If you are carrying 4 pounds of battery, how hard to pedal can it be?

I just thought your ride was long, and fairly punishing. So even if you slowed to 20 mph cruise, you'd still be carrying 10-15 pounds of battery?
 
Another kind of foreign concept for you. Run a typical dd motor on 48v 20amps controller. 27 mph top speed for the 9x7 windings.
1200w max power.

I could not make one fail at that power level. I tried like hell on street. Only off road riding on stupid grades would do it.

Then it never matters what happens when it melts. It doesn't fail. I have motors with 8000 miles on them like that. That's what others were saying earlier. DD motor, run it so it wont break.
 
I see your point dogman, but problem is that mac and DD motor are too heavy duty for my purpose. Too (power) hungry.

I'd like to minimise the amount of power used just to reach to speed and keep pace via pedaling with my (maybe) 100W human leg power :lol: Or maybe assist a bit for a total of 300W motor + 100W power.

With a DD at 27mph, it'll pump close to 1000W. So if I run out of battery, same old, same old.... 3 months ago, I went out to see a friend with my DD, controller failed. Damn it, it was death to meet them. I was so slow that when I arrived to destination they went back home!


See the quote from Kepler:
Had a great ride into work this morning. Really starting to push this bike now and managed to do the 28km ride in just over 50 minutes which was the same as I was doing on my Fighter. Difference is that the Fighter (with geared hub motor) used 15 Whrs/km with the Super Commuter only using 6.9 Whrs/km.

I am typically at 250W most of the time, going to 500W when in a hurry and and bursting to 800W only occasionally. So my motor spends most of its time at 3 or 4amps. Quite an easy life for this motor. It hardly even gets warm
http://www.endless-sphere.com/forums/viewtopic.php?f=6&t=47139&hilit=super+commuter&start=175


Between his optimised road bike and his normal geared bike, there's more than double power consumption. So something in between for me would be good. Like 800W peak. And mostly around 500W. Or less. Electronic has to be complementary to my ride. And not the opposite.

It has to be like a proper road bike when unpowered. (I'll also have a proper high power bike)
 
Just having trouble wrapping my head around you riding less than 1000w. If you do, anything will get much more reliable.

But nevertheless, the speed he just talked about, without stops, should get you damn good wh/km on just about anything.

Switching to yank measures, 18 mph or so. Takes about 300-350 watts, just as you were speaking of. And on any bike suitable for pedaling, you can put out another 100w with ease. so 250-300w seen on the CA is not unusual at all.

But just a few stops along the way will pump that wh/km number through the roof.

Please don't misunderstand me. I highly support your idea to make a second bike, that will be more reliable, more efficient, and pedal nice. Something in a gear motor will be perfect, but unless you are willing to sacrifice performance leaving the stops, it might best be a motor with a bit more beef to it. I just fear the stop and go will eat a very small motor alive, if you give it more than 800w leaving a stop. So that's talking controllers in the 10 amps ballpark if you run 48v.

It's the punishing urban ride I worry about. It doesn't get much more urban than where you ride, unless it's Mumbai, or Shanghai.

Pedaling more on a more comfortable bike is always better IMO, for your health. I just don't want you to have overly optimistic expectations of it's performance. But hell, if Luke can build a light bike and get into pedaling it, so can you.

Whatever motor you use, you can still run your cruise at whatever wattage you choose. It could be a gigantic old crystalyte and still get 15 wh/km. As long as the speed is low, and drag not too bad, and you are pedaling your 100-200w.

But for sure, if you did break down, you will like pedaling a 7 pound motor much better than a 15 pound motor. But you won't break a medium size motor, at 400w.
 
So if you want to PEDAL, just do it! Buy the road bike and pedal.

I read you destroyed to rugged geared hub motors. I sure wouldn't put a peewee mini geared hub on it and expect it to survive.

So, do you know what killed the MAC or Bafang? Most cases it repairable. Cut back a little on the power and do some of the work.

Yeah we all destroy stuff, but what fun would it be without it.

I still want to know how you burnt your MAC.

Dan
 
As they're very cheap, a 36v Q100H with 12S should work. You can use a 5aH pack for short journeys and double it for longer ones. A 5aH pack will give you about 10 miles and it can fit in your pocket. With that setup, you'd get a real speed of about 24 mph. My friend just got an old steel roadbike from Gumtree. The guy advertised it at £10, but when Steve got there, he said he could have it for nothing. It's perfect for conversion with a rear Q100. The advantage of the Q100 is that you can swap cores very quickly, so easy to change between 201, 260 and 328 rpm, plus, with lipos, you can change the voltage easily too. 10S and 12S are the best because you can use the cheap 36v controllers like the KU63. You can solder the shunt in the KU63 to about 18 amps, and it still stays relatively cool.

You can make your own 12S battery out of 18650s. 12S3P would be about the minimum, which would be about 2kg for 9aH, but I think they'll sag a lot more than decent lipos.

So, 36v Q100H, 5aH 12S lipos, KU63 with 20% soldered shunt at 18 amps. Speed about 24mph, weight about 4kg, range about 10 miles. Add 5aH and 1.5kg for 20 miles range.

I feel your frustration with the previous answers you've been given. Some (most) people don't read what's written.
 
Thanks D8veh, it does feel that here most people are not used anymore to pedal and immediately propose some beefier motor made for 1000W+ power. Fast and powerful!

But I also see your point dogman, start and stops are what worries me the most. So some high torque motor would maybe make sense. Start and stop was what destroyed my BPM actually, not heat. Clutch dead!

I really like the idea of the Q100H. I'm thinking to do it. I think it would be a good plan. I was thinking to get an 14s4p of some good 18650 cells. With this capacity, I can even use low discharge rate cells without too much sag. Or maybe the Xionga? motor is more expensive but shipping cost is lower... so it's about the same price.

I'm in discussion with a guy from pedelec to maybe buy his (old) electric bike. It would maybe be a good alternative as it looks so cheap I should be able to park it outside overnight without too much worry.
 
IF you are ready to pedal, it's not a problem. Pedal till 10 mph, or the first 10 feet, then give er the throttle. Then you can get away with a faster wind small motor. You won't stress the clutch much at all if you pedal just 4 real hard pumps first.

But you won't be riding the lightweight rig just like you rode before. It will feel nice if you get into the pedaling, and be light enough to go up your stairs.

Little rear gearmotor, and carry at most 8-10 ah of 12s. About 8 pounds of battery. Works great, but the question is, will you pedal that hard? I Just had the impression you much preferred not pedaling until it did break.

Certainly not expensive to try it.
 
#1 with Dogman you want to peddle ? Peddle to 10mph before touching the throttle lightly for 18mph. A mnc battery for weight. No magic for ebikes.
 
cwah said:
I see your point dogman, but problem is that mac and DD motor are too heavy duty for my purpose. Too (power) hungry.

I'd like to minimise the amount of power used just to reach to speed and keep pace via pedaling with my (maybe) 100W human leg power :lol: Or maybe assist a bit for a total of 300W motor + 100W power.

With a DD at 27mph, it'll pump close to 1000W. So if I run out of battery, same old, same old.... 3 months ago, I went out to see a friend with my DD, controller failed. Damn it, it was death to meet them. I was so slow that when I arrived to destination they went back home!


See the quote from Kepler:
Had a great ride into work this morning. Really starting to push this bike now and managed to do the 28km ride in just over 50 minutes which was the same as I was doing on my Fighter. Difference is that the Fighter (with geared hub motor) used 15 Whrs/km with the Super Commuter only using 6.9 Whrs/km.

I am typically at 250W most of the time, going to 500W when in a hurry and and bursting to 800W only occasionally. So my motor spends most of its time at 3 or 4amps. Quite an easy life for this motor. It hardly even gets warm
http://www.endless-sphere.com/forums/viewtopic.php?f=6&t=47139&hilit=super+commuter&start=175


Between his optimised road bike and his normal geared bike, there's more than double power consumption. So something in between for me would be good. Like 800W peak. And mostly around 500W. Or less. Electronic has to be complementary to my ride. And not the opposite.

It has to be like a proper road bike when unpowered. (I'll also have a proper high power bike)

The approach I took with Super Commuter worked well but it took a heap of work and experimentation to get it where I wanted it.

The easy way to get the results you are after is just to go to BBS02 750W fitted on a nice light flat bar road bike like you pictured. A couple of 6s 5ah LiPo's to stay with the light weight theme and you are good to go.

Next trick is to re program the drive so all the speed limits are removed on all PAS settings. By doing this, you can keep the PAS level low without having any speed restrictions.

I have built a few of these now and everyone has been more then happy with the result.

Remember you will need a bike with a standard 68mm to 72mm bottom bracket if you decide to go down this path.

For what you want to do the BBS02 is a no brainer IMO.
 
frammis3001@yahoo.com said:
Is amped bikes still in business? Nobody answering phone, no email reply.

Did you read the message on their site?
We are currently inundated with calls. Most calls average 10-15 minutes working with customers. We are here, just retry in a few minutes.
(with the exception of holidays and wekends) so please try back in a few minutes.

Patience / Persistence ?

Can you consider adding your location to your profile? It can be helpful at times. (user control panel, profile- 7th line down)
 
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