Please help me with new ebike design!

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Liamo0o
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I am seriously considering building this model of ebike for an environmental science project and also to make a future to mile daily commute for summer classes:
Youtube video of motor and batteries pushing bike on simple drivetrain

The drive train is just a quick setup to show how good the motor and batteries are.
The drive train shown has nothing to do with the capabilities of the technology this entire site and movie is about.

600 max continous-800 watt peak motor but it has a better rpm range than a 24volt brushed scooter motor by far and weighs only 8oz!!!
sllofly_motor.jpg
This shows you how little components actually make up the system compared to the standard 50 pound bike.
The same motor with a freewheeling drive train, geared and a shoebox of batteries would take you the distance.
slofly_bike.jpg
Cheap
slofly_cheap.jpg
This is a servo control used for a throttle.
slofly_servo.jpg
The smaller, lighter and more powerful the batteries the better.
slofly_batt.jpg
slofly.jpg

http://www.slofly.com/ebike/
http://www.bikeforums.net/archive/index.php/t-165678.html

The problem is there is no real tutorial! and I don't really know what I am doing. I have looked into HUB motor kits as well but they are much more expensive and aren't as appealing... please help...

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MB-1-E
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Re: Please help me with new ebike design!

Hi Liam,

It would help if we knew what bike you were planning to put this on.

Have you thought about the Currie Pro-Drive
http://www.carterrv.com/usprodrive/usprodrive.asp
It will only fit certain types of bikes, so you'd need to check the site to see if your bike would be a good candidate or the kit.

It's a little more expensive but might be a better investment. I think these come with pretty good instructions too.

As far as using the outrunner motor, you could probably pick one up at Hobby Lobby online.
I noticed that in commenting about the motor, they said it hadn't been tested in this capacity much.
You would probably stand a good chance of burning out any controller and maybe the motor since it's not really designed for this type of thing.

I think that by the time you purchased all the parts, burn up a few parts getting the right setup and buy a good lipo charger and enough Ah to get you anywhere you will end up spending about what you would pay for the Currie Kit.

That's just my opinion, so take it with a grain of salt if you will. I just think it's just asking that motor to do quite a bit. I could be wrong but I'd think about getting a brushless scooter motor, maybe a 400W with a couple of AGM batteries and a 60 Amp controller. You could probably buy the individual parts and find some good instructions here or elsewhere.

Good Luck on your project and keep us posted on what you decide to do.

Dave

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Liamo0o
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Re: Please help me with new ebike design!

wow,
thank yuou very much for your reply. Here is the bike I would be sticking it on, 2005 kona blast

http://www.konaworld.com/bikes/2006/blast.htm

I believe it is 26'' (I measured from end of rubber to end of rubber) - I am 6'0 165 lbs

thanks very much for the currie drive motor, this is making my decision much harder
the main thing I am struggling with is the lack of any sort of engineering background or skills... The carrie kit seems much easier...
Has anyone had any trouble with theft of these engines or bikes? I am not a big safety nut but will be attending UCSD this fall
I would also be able to bike while the motor is running - is this possible? Thanks again

~Liam

Gman
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Re: Please help me with new ebike design!

Spokes Stainless 14g
Tires Nokian NBT 26 x 2.1
Rims ALEX Ace-18

Peace Out,
Gman

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MB-1-E
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Re: Please help me with new ebike design!

Liam,

Nice Bike! I think that the Currie setup would work fine with the Kona ... the only problem that I can forsee is the rear disc break. If it's on the right side (same side as the derrailer) then no problem.
If it's on the left side then it might interfere with the Currie conversion, but I'm not sure.
A call or trip to a good LBS might be able to resolve that.
Sometimes these types of little issues just become challenges and can usually be worked around one way or another, so I wouldn't give up on the Currie or similar system.

I believe Sturdly (one of the members here) has the Kona Blast and may have considered the Currie setup.
He might be able to tell you something about bike specific issues.

Even though you don't have any engineering background, most good kits are designed with this in mind and usually anyone with enough determination and the ability to research and seek the help of others can and will do fine.

Security is something to be concerned about.
I'd be wary of someone stealing the whole bike.
A good bike lock and habit of using it should help a lot though.

Yes, you can pedal with the motor running or not.
The Currie has a freewheel on the motor drive sprocket that lets you pedal at will and won't turn the pedals when it powers the bike.

Dave

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outrunner
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Re: Please help me with new ebike design!

Maybe we can make an 'open source' kit
One made by a group effort of hobbyists and machinist around the country.
Together we make the ultimate bike.

Here is a link to the above bike on this forum:
http://tinyurl.com/2y3a66

Liamo0o
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Re: Please help me with new ebike design!

outrunner - your rig was the one that motivated me to electrify my bike - have you had any problems with your setup - did motors blowing up and so forth, do you think it would be better for a newbie like me to attempt to build a practical rig like your or get something like a curie conversion kit

Liamo0o
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Re: Please help me with new ebike design!

hmm.... doing more research on the curie design - this is the most probable choice... I bike at a standing rate of around 15-18 MPH will that be perfectly converted with this curie setup, meaning if the motor speed goes 16-18 mph will I be able to eaching a standing pedalling speed (with motor on) of 32-35 (excluding the extra weight of motor/ batery on my standing speed)

reikiman
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Re: Please help me with new ebike design!

From my point of view the absolute dead simplest thing to do is the GoHub or Wilderness Energy conversion kits. No messing with sprockets and chains and stuff, just wires. Plus they're silenter. Then if you think you want something different you can always play with rigging up something that uses sprockets and chains.

- David Herron, http://davidherron.com/

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Liamo0o
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Re: Please help me with new ebike design!

Im fully willing to spend the extra time on a curie conversion kit. I've done a lot of research and found that the hub motors are about the same price as this curie on ebay http://tinyurl.com/26j93l
I like the fact that there is no huge batt pack on the back and the overall look
+ any word on the previous comment of 17 pedaling + 17mph motor = 34mph ???

Sturdly
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Re: Please help me with new ebike design!

I agree with Dave as to the ease of installation of a Go hub motor. However the Kona Blast offers some challenges to fitment. Put it on the front and you should swap out the suspension fork for a solid chrome moly like the Kona project one, add up to $100 or so to the cost. You will also have to get a good V brake and loose the disc add another $50 or so.

The Pro drive will work but again you will loose the disc brake, not so important as it is the rear, add $50 or so for a quality V brake. You will also loose the ability to attach a nice rack to the drop outs. I'm no fan of the post mount jobs especially if you carry any weight like groceries. The good news is that you can get a sprocket from EVDeals that will bolt up to the disc mount on the hub which is far superior to the spoke clamp method of attachment.

As for security get the best lock you can afford and use it ! I also have a seat leash and a wheel leash as these parts beg to be stolen with the quick releases.

Unless they are SLA's carry the jewels (batteries) with you when she's parked !

Liamo0o
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Re: Please help me with new ebike design!

Thank you for your reply but is a bit saddening... I don't really want to sacrifice higher quality parts much less pay for lower quality parts. Id be willing to sac. a rear DB and a rack but what I'm really concerned about is will I be able to pedal while the motor is running to achieve a speed in the 30mph range.

EDIT: is there any way I could *tweak* it to achieve this result?

Thanks,
Liam

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Re: Please help me with new ebike design!

`Liamo0o,
I don't know if your aware of it or not, long urls won't work as links.
You can do a TinyURL.
They can also be created from your Browser:
IE - http://tinyurl.com/,
Firefox - https://addons.mozilla.org/en-US/firefox/addon/126 or http://mozmonkey.com/tinyurl/ are just a few.
Opera - http://widgets.opera.com/widget/4080

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Liamo0o
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Re: Please help me with new ebike design!

thanks for the heads up, anyone have an answer to above question?

MB-1-E
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Re: Please help me with new ebike design!

Hi Again Liam,

Currie does make the 600W kit and there are aftermarket motors and gears that can be changed etc, but the problem is that, as you get into larger motors and lessen the gear ratio, there is more work for the batteries and controller so those would probably need to be upgraded as well.
Depending on the terrain you traverse this "extra" load on them could lead to failure.

Here's a site that points some of that out.
http://www.theworkshop.ca/energy/ebike/ebike.htm

Be aware that most states or countries for that matter have limits on what is a legal speed and what sized motor constitutes an unlicensed electric bike and what is not. Here in Washington the limit (I believe) is 20 mph and 1000W respectively, but that may differ where you live. There are also provisions in the law that state that it must be a pedal assist to comply. You should be sure what your local law allows before you make any purchase.

I doubt you'd have a problem if you respect the law on this but you do want to consider what would happen should you ever get into an accident. If your bike were found to not comply, you could be fined for operating an illegal vehicle etc. perhaps with some hefty fines.
Something to think about, for sure.

Just some food for thought.

Dave

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Liamo0o
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Re: Please help me with new ebike design!

... but assuming I lived in Liam-land and I wanted to increase the speed above 20mph (with or w/o extra pedaling) simply for proof of concept - do you know a way I could do this?

MB-1-E
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Re: Please help me with new ebike design!

Bigger motor (higher watts), more batteries (more Ah), higher amperage controller, reduced gear reduction.

Each has it's drawbacks.
The larger the motor, the more current it will draw.
The more batteries, the more weight & cost.
The higher amp controller, definately higher cost.
Reduced gear reduction, not as good on hill climbing.

For every change you make, something has to account for that change.
IMO, the 600W system as sold is likely the best effiency and use of that particular equipment.
Figure that a team of engineers probably worked on getting the most out of this setup.

Perhaps use of the Hall Effect throttle might help.
Set it up and maintain it as specified.

That's my 2 cents.

Dave

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Liamo0o
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Re: Please help me with new ebike design!

but there is nothing I can do to make it so I can pedal hard to increase speed without hurting my rig?

NickF23
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Re: Please help me with new ebike design!

Pedalling is good, you won't hurt anything but if you pedal yourself above the motors top rpm (assuming fixed gearing) you'll be doing all the work. worth buying a cheap motor like the currie, lots and lots of room for modifications, different gearing and speed etc. If your interested in learning about how EV's work then also worth getting an amphour meter like the "wattsup http://tinyurl.com/22a2ko

you might also find these calculators helpful

http://www.kreuzotter.de/english/espeed.htm

http://www.ebikes.ca/simulator/

Liamo0o
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Re: Please help me with new ebike design!

I understand Ill be doing all the work, but isnt the motor built so even when you pedal you can't get a decent speed above 20 I have been hearing very mixed things, can someone clear it up pllzzzz

Gman
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Re: Please help me with new ebike design!

`Liamo0o,
Maybe if you explain exactly what your trying to build, it would help. It sounds like your looking for something where you do most of the work.
POWER ASSIST FAQ

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Drunkskunk
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Re: Please help me with new ebike design!

I like that original design up there. Its all RC airplane parts!
the down side is there would be no way to keep that motor cool. they were designed for having 60mph+ wind forced over them for cooling. 800watts is a huge amount of power for such a tiny motor to handle.

The Currie system is great and all, lots of room to modify things, but its complicated, with many diffrent parts. An easier system to build might be the Crystalyte line of brushless hub motors. Imagine that first little outrunner motor, only with spokes laced to the outside of the motor, and made bigger to handle the heat, and you have the idea of the Crystalyte motor.

They can also be built to be better hidden on the bike. Mine is near silent, does 22mph (i built it to be slow) and has a range of more than 20 miles at 15mph. I've ridden with people who didn't know I was on an electric. here's a pic:

Click here for full size view

Liamo0o
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Re: Please help me with new ebike design!

shwag thats pretty nice... Ive looked into all the kit options and think the curie is my favorite - I'm not really considering the above friction drive anymore... I'm sorry if I'm not being clear but...while you were riding did you ever go faster than 22mph without *nominal* pedaling? won't there be some kind of safeguard in the motor such as an intentionally low rpm speed to inhibit me from going much faster than 20? My main desire for an electric bike is to speed up my commute (10mi) not make it easier. And allow me to pose this question to you - have you have wanted to go more than 22mph on your bike and felt you could not?

Drunkskunk
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Re: Please help me with new ebike design!

Just to be clear, mine isn't a friction drive either. The motor is the back wheel.

when I mentioned 22mph, I ment no pedaling at all, riding it around like a motorcyccle. If I pedal, I can and do hit 30. Crystalyte motors come in a choice of speeds, I picked one of the slower motors, and I'm only running 48 volts through it. This motor is capable of 30mph on my bike if I were to bump the voltage up to 72V.Even faster if I used a road bike instead of a mountian bike. 72V is still within specs for both the motor and controller I bought, with no speed restrictions.

As for your Currie motor, you won't have a problem peddling faster than the rated speed unless you're lance Armstrong, and can pedal faster than the motor's max RPM. If the controller has a speed limiter, then it will kill the motor and you're on your own for pedling, otherwise, you're just adding your force to the motor's to increase the speed.

Gman
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Re: Please help me with new ebike design!

` :?
Thanks for clearing that up, building a e bike for your environmental science project is no longer your initial goal?
Your goal is to go about a mile at above 20 mph, correct?
I don't have that much knowledge about E Bikes as the others who have posted. I believe your max speed is based on several variables, which they have tried to explain.

Quote:

have you have wanted to go more than 22mph on your bike and felt you could not?

The answer is yes, but you dance with the one that brung you. I know to achieve greater than 22mph I would need additional wattage etc. which are a additional cost. I would think what your looking for is a system that will go over 22mph unassisted, unless you are capable of pedaling that fast.

Crystalyte Home Assembly Guide

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Gman

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Liamo0o
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Re: Please help me with new ebike design!

arrr... getting many mixed responses, one guy was saying before if I went over 20mph I would be doing all the work myself and your saying above 20mph its power assist???? I need to talk to a rep or something.... thank you all for all your responses

Gman
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Re: Please help me with new ebike design!

`Sorry for the confusion, follow the others, I missed the post before I posted mine.
The e bike will be doing the 20mph if it's capable, and you just pedal for the exercise or to conserve battery power or for steep inclines etc.

Peace Out,
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Now that we have clarified our beliefs, your invited to join us as we begin building on them to define our Community Mission Statement

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Liamo0o
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Re: Please help me with new ebike design!

... I'm dumbfounded - I don't know if I have a learning disability or not but it seems like a yes or no should answer my question

Drunkskunk
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Re: Please help me with new ebike design!

I'll try to clear up some of the confusion if I can.

you asked : (".....what I'm really concerned about is will I be able to pedal while the motor is running to achieve a speed in the 30mph range.(?)")

The Simple answer is Yes

But the full answer is pretty complicated. If you can pedal a bike at 15mph, and the motor can run it at 15mph, when you add them together, they will only give you about 20mph top speed.
Why?
Wind resistance. Wind resistance is the biggest factor limiting your speed on a bike. The problem with wind resistance is it builds up exponintialy.
Lets say it takes 100 watts to go 10 miles an hour on a certian bike. it might take 200 watts to go 15mph, and 400 watts to go 20mph.

The average person can put out about 200watts sustained on a bike. if you're athletic, it can be higher. lance Armstrong maintained around 373 watts output in the Tour de Farce. If you are going for shorter time frames, you can put out more.

To hit 30mph with pedling, you will probably need a 600 watt motor or better. Running a road bike instead of a mountian bike would make it much easier to reach your goal, but I think it's do-able on the bike you picked with a Currie.

Liamo0o
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Re: Please help me with new ebike design!

Thank you!! that was perfectly clear. One caveat - when you say its do-able on my bike with the curie I picked are you talking about 30 mph sustained if I normally bike 17 sustained?

Drunkskunk
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Re: Please help me with new ebike design!

With the 600 Watt Currie, yes. You pedaling at 17mph is worth about 200+watts, so a combined output of you and the motor will be around 800 watts. It will take a good deal of tweaking, but its certianly posable to do 30mph with a combined effort of 800 watts.

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