Bicycle question, three-wheelers??

Bikes, trikes, personal mobility and getting to/from the event - this is the place to discuss general transportation issues.
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Re: Bicycle question, three-wheelers??

Post by TinkerMom » Thu Jun 28, 2012 6:49 pm

This is my next installment for my trike. I found an old pony cart. Stripped it down, bent the shafts, fabricated a hitch to go behind my trike.
Next step; paint, upholster the seating and lights.

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Re: Bicycle question, three-wheelers??

Post by FIGJAM » Thu Jun 28, 2012 6:51 pm

FIGJAM wrote:Let's go, let's go, LET'S GO!!!!!!!!!! (Bump)



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Re: Bicycle question, three-wheelers??

Post by Shoeshine » Sun Jul 01, 2012 10:21 pm

Hey Figgy,

Any chance of getting details (source and/or specs greatly appreciated) for your trike motor ? I have plenty of amp hours in the bank and mechanical bits are do-able for a construct like that but I am woefully ignorant whaen it comes to acquiring motors. No love on craigslist (at least for what I know how to search)

Thanks in adavance
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Re: Bicycle question, three-wheelers??

Post by FIGJAM » Sun Jul 01, 2012 11:04 pm

OK, my motor came with the trike.

It's a 12 volt dc, reversable, 200 watt, 2100rpm, 40 continuos amp, motor.

Whatever all that means. :?

I had your problem when looking for a backup in case I needed it.

What I found was that all the new friction drives were 24, 36, or 48 volts.

While doing the research, it seems there are people using old treadmill motors, but I was having a hard time finding out which ones were 12 volt.

I'm not that tech savy, but my 105ah battery gets me about a 30 mile range.

If you go 24 volt, you'll need to use 2 batteries hooked in series, but I don't know what that will do to the range.

It may be more efficiant, but again, I'm not sure.

Hope this helped. 8)
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Re: Bicycle question, three-wheelers??

Post by gyre » Sun Jul 01, 2012 11:52 pm

It means it's a highly specialized motor.

Get a higher voltage one with a good controller.

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Re: Bicycle question, three-wheelers??

Post by Shoeshine » Mon Jul 02, 2012 12:12 am

Thanks Fig,

I hear ya Gyre. The issue is tthat I have a 12v system in the bag. 2 - 6v golf cart batteries in series run my camp systems as they are (lots of 12v stuff easily availible, I already have lights, blender, etc...). My chargers, both solar and conventional are geared to that as well. For me to get to 36 or 48v to make use of elec bicycle motors would require a serious investment.I was hoping there was a 12v ... easily aquired solution. I guess it is a matter of finding that 40amp motor?

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Re: Bicycle question, three-wheelers??

Post by gyre » Mon Jul 02, 2012 12:27 am

You could use a step up transformer.

Some controllers do this.
There are good reasons for most motors to be higher voltage.

Often the nominal system voltage is much lower than the motor voltage anyway.

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Re: Bicycle question, three-wheelers??

Post by Shoeshine » Mon Jul 02, 2012 12:42 am

Is such a step-up transformer easily (and somewhat cheaply) availible? like I said I have the battery bank on hand, and the mechanics are easy using bicyle parts. I am however a layman when it comes to electrical systems. So far using 12v throughout has made my electrical connections simple.
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Re: Bicycle question, three-wheelers??

Post by gyre » Mon Jul 02, 2012 1:17 am


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Re: Bicycle question, three-wheelers??

Post by FIGJAM » Mon Jul 02, 2012 7:20 am

Here are some options, but it does'nt say whether their 12 volt.


http://www.electricrider.com/parts/motors.htm

I think mine is either 1/3 or 1/2 hp.

The treadmill motors were up to 3hp.

Probably use a lot of juice.

Some guy wanted a 12 volt box fan to run at his off grid house.

He just took the fan off a household box fan and replaced it with the treadmill motor.

That's why I think it would be good for a bike project.
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Re: Bicycle question, three-wheelers??

Post by FIGJAM » Mon Jul 02, 2012 8:12 am

Here are some other options, but they ain't cheap! :shock:

https://www.google.com/search?sourceid= ... t+dc+motor
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Re: Bicycle question, three-wheelers??

Post by unjonharley » Mon Jul 02, 2012 11:20 am

FIGJAM wrote:Here are some other options, but they ain't cheap! :shock:

https://www.google.com/search?sourceid= ... t+dc+motor
People are letting there 24v scooters go on Craig's list for 20 30 buck.. Gives ya all the wiring and switches you'll need. And trade in batteries..

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Re: Bicycle question, three-wheelers??

Post by Canoe » Mon Jul 02, 2012 11:31 pm

Keep in mind that there's a 5 MPH speed limit.
So if the electric part is just for BRC, you'll likely be fine running a 24 VDC or 36 VDC motor with just 12 volts. The controller would just be regulating down the supplied 24 or 36 volts to a drive voltage that would draw current to drive up to 5 MPH.

I assume you're not running one of the brushless DC motors one typically sees in e-bikes, that require an entirely different kind of controller than a brushed DC motor.
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Re: Bicycle question, three-wheelers??

Post by Shoeshine » Tue Jul 03, 2012 12:07 am

Wow, interesting confluence of ideas there.

So just to make sure I am understanding this correctly...

If I got a scooter off of CL and wired in my 12v battery bank, The motor controller from the scooter would just feed in voltage from 0-12v in the lower range of the throttle?

Do these motors have enough torque to use effectively @ 5mph in the lower range?(asssuming of course it was geared correctly, Im thinking of using a standard 26" rear bike wheel assembly with multiple motor to hub gear options)

For example http://sandiego.craigslist.org/nsd/mcy/3114152520.html Now this is a 36v scooter, but it is spec-ed out to do 15mph w/ a 12mile range on 10amp/hr batteries. Were I to pull the drive and electrical system from this and apply it to my trike, could I expect to get 3-4-ish mph with an extremely extended range with my 105 amp/hr 12v deep cycle? (I understand there will some loss due to weight and conditions) I am looking to create a crawler/hauler for multiple year use at BM not a speed demon or road bike.

Loving this thread.

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Re: Bicycle question, three-wheelers??

Post by gyre » Tue Jul 03, 2012 12:20 am

They're all different.

Gearing, controllers.
Using lower voltage, if it works, will be less efficient.

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Re: Bicycle question, three-wheelers??

Post by Shoeshine » Tue Jul 03, 2012 12:34 am

I appreciate the input Gyre.

Is there any good way of determining if what I proposed would work? (without just trying it, an option I am not opposed to BTW, lord knows I will probably use all the parts someday, just trying to focus my funds)

how would one start to think about the loss of efficiency in a real world situation (as much as BM is the real world)?

Thanks
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Re: Bicycle question, three-wheelers??

Post by gyre » Tue Jul 03, 2012 1:42 am

Research.
Forums.
Get on a scooter and see if it will take you ten feet.
The unregulated motors are usable, but very annoying, and inefficient.
Most are on/off.

I have a scooter someone gave me.
Determined it was cheaper to use zero parts from it.
Capable of zero travel on the playa.

I have a nice scooter kit.
Too heavy to use on a bike.

You need the right stuff for what you're doing.

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Re: Bicycle question, three-wheelers??

Post by Shoeshine » Tue Jul 03, 2012 2:14 am

Fair enough.

I guess I was just hoping that the collective wisdom here might give me a shortcut. I'm all about trying shit.

Was also hoping that I might get a few pointers from folk who had tried these things before me. eliminate the dead ends. save myself afew bucks in prototyping.

No worries... I'll test it out, but thanks.

Was kind of under the impression that this WAS research and asking questions on a forum. My apologies if it was inapropriate.

Regardless this thread has given me a few more avenues to explore. I'll do so.
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Re: Bicycle question, three-wheelers??

Post by gyre » Tue Jul 03, 2012 5:40 am

I just don't know simple answers.
The basic hubkits are made for different wheel sizes and also made in different gearings and wattage ratings, for high and low torque use, even very high torque like pedicabs.

Some use direct voltage.
Others won't run without a controller.

Hubkits have the advantage of flexibility, moving from one bike to another.
Quality ranges from noisy crap to durable, like heinzmann.

Most efficient are motors driven through gears, which complicates design.

When you open your choices up, it really gets complicated, as there are many versions of motor design, and efficiency.
It also gets way beyond my engineering knowledge too.
Check catalogs for a bewildering range.

I do know low voltage dc motors for low rpm get expensive, and harder to make.

The forums know more than I do.

Pana makes the best gear driven assisted bike set.
There is an xtracycle kit, and a few others out there.

Heinzmann has a selection of kits and bikes.
There are a range of others, some good, many not so much.

My scooter kit is similar to, and may come from a forklift or golf cart.
Curtis controller.
Engineered by someone with more background than me.
It once had a beautiful nicad air cooled battery set, which blew up and nearly destroyed a shop.
Replaced by a small turbine.

I have an italian L'eco kit, which seems decent quality, less than the heinzmann.
It actually has no real controller, like most.
I hope to add one.

You can buy complete bikes in lead batteries, cheaper than you can build one.

A good motor engineered right can be very efficient, and as low as 250 watts.
At times the playa requires more power, but 450 should be adequate.

I am more interested in getting a surly front wheel kit, or entire bike eventually.
The surly requires a rear wheel hubkit, or re-engineering.
The wider tires become much more efficient as the playa surface gets worse.

I was originally interested in building a trike, but transport is harder, even with breakdown, and so is engineering one properly.
There aren't many factory built.
A hubkit is an option for the front wheel though.
I prefer gear driven.

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Re: Bicycle question, three-wheelers??

Post by FIGJAM » Tue Jul 03, 2012 7:10 am

Maybe this will give you some ideas.

http://www.instructables.com/id/How-to- ... -than-100/
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Re: Bicycle question, three-wheelers??

Post by gyre » Tue Jul 03, 2012 7:16 am

Note that pedals are required at burning man.
And just a damn good idea.

This is similar to the xtracycle though.

Almost every driven electric uses hubgears, due to the chain issues.

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Re: Bicycle question, three-wheelers??

Post by gyre » Tue Jul 03, 2012 7:25 am

FIGJAM wrote:Maybe this will give you some ideas.

http://www.instructables.com/id/How-to- ... -than-100/
The powerchair motor is probably a good idea.
Make sure you get the complete set, with controller.

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Re: Bicycle question, three-wheelers??

Post by FIGJAM » Tue Jul 03, 2012 8:05 am

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Re: Bicycle question, three-wheelers??

Post by Canoe » Tue Jul 03, 2012 11:39 am

Shoeshine wrote:...If I got a scooter off of CL and wired in my 12v battery bank, The motor controller from the scooter would just feed in voltage from 0-12v in the lower range of the throttle?...
The motor would be fine, but not necessarily the controller.
The controller will be expecting to be supplied with the specified supply voltage. As the battery depletes its charge, its voltage drops, according to its performance curve. Different curves for different types of batteries. Controllers are designed not only for a target voltage & current, but also for the type of motor they'll be driving and the type of battery supplying. Each controller will have a minimum voltage it must have for its circuits to work, and enough over that to provide a voltage to the motor. So if your controller expects a supply of 36 VDC, but needs a minimum 24 VDC for the controller to work, then it will not run with a 12 VDC battery, even though the 36 VDC might be controlled down to 8 VDC for driving the motor at lower speeds.

And, as Gyre points out, although it will work, each motor has its best efficiency point. So using a motor that will drive the scooter to say 30 mph, but moving that same weight at 5 mph, will use more power than an optimal motor at 5 mph but with a top speed limit of 7 or 8 mph. But it will work.
That said, a motor designed for a top speed of 20 or 30 mph, geared down using bike gears to a top speed of 8 to 10 mph, would put you in the ball park of good efficiency at 5mph, with the bonus of likely being able to pull a good load.

And I don't know of any systems designed for 5 mph, except for some golf cart types, which are usually actually designed for 20 mph, but with a limiter added on the controller for sale in certain markets or applications. Many e-bikes are not efficient in the speed range they actually used in for the same reason: they're limited by the controller (set to meet laws in that jurisdiction) to a given max speed, but the most efficient speed for the motor is above that. But the good ones are efficient enough, just not optimal; so your battery pack may provide a range of 24 miles instead of 30 miles. Although the high-end battery packs are expensive, buying more pack is cheaper than a very expensive motor & controller optimized to your exact application.
Shoeshine wrote:... I was just hoping that the collective wisdom here might give me a shortcut. I'm all about trying shit.
Was also hoping that I might get a few pointers from folk who had tried these things before me. eliminate the dead ends. save myself afew bucks in prototyping....
It's just that there are so many ways to do it and many variables for each.
Gyre's explanations are just barely touching the top of the various subjects you'd have to acquire knowledge of in order to predict a successful outcome.

So, you're faced with possibilities of:
- go and acquire a lot of knowledge (way more than one would think)
- buy/copy something known to work at that speed & weight range that has already been engineered by someone else
- grab something cheap and easy, and hook it up and see what happens (I'm assuming you have enough knowledge of electricity to properly wire & manage these drive currents safely).

I used a cheap brushed motor with a variable range controller to ensure that the voltage curve of my battery pack stayed fully within what it will work with, so I can limp home if I'm pushing the limit.
http://eplaya.burningman.org/viewtopic. ... or#p812180
This is not the best solution, but for many applications it is a working solution.
I see the controller I got is up in price, but it comes with a throttle twist grip.
http://tncscooters.com/index.php?route= ... uct_id=188
They have the motor at 24 VDC and 36 VDC, both at 250W and 450W.
Bracket for mounting on a bike. http://tncscooters.com/index.php?route= ... uct_id=499
The 24 VDC motors would have the best chance of working well with 12 VDC.

I'm running 48 VDC from my LiFePO. I should see what that controller does when supplied with 12 VDC, and what voltage the motor is getting at 5 mph and when towing.

It's very easy to spend a lot of money on the quality parts. But, before you do, make sure they're the parts you need, or you'll just end up buying something else later.
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Re: Bicycle question, three-wheelers??

Post by FIGJAM » Tue Jul 03, 2012 12:42 pm

This is why I like my friction drive.

It's designed for a top speed of 10 mph with the 1 1/2" drive roller.

By putting on a roller half that size, I get 5 mph, while the motor still runs at it's peak.

It just keeps things so simple.

Just like me! :lol:
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Re: Bicycle question, three-wheelers??

Post by Canoe » Tue Jul 03, 2012 3:13 pm

FIGJAM wrote:... It's designed for a top speed of 10 mph with the 1 1/2" drive roller. By putting on a roller half that size, I get 5 mph, while the motor still runs at it's peak...
And should have more torque for pulling loads.

I checked the 24 VDC controllers. Most have an undervoltage cut-off to protect against over-depleting the battery. Cut off is around 20.5 volts, but they say the actually voltage varies greatly. So they will not work with a 12 VDC supply. You need a 12 VDC controller. Perhaps a really heavy duty op-amp or a high-current V-FET on the low side, gate driven by a POT for a throttle. Need a good heat sink on them.
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Re: Bicycle question, three-wheelers??

Post by unjonharley » Tue Jul 03, 2012 6:07 pm

Canoe wrote:
FIGJAM wrote:... It's designed for a top speed of 10 mph with the 1 1/2" drive roller. By putting on a roller half that size, I get 5 mph, while the motor still runs at it's peak...
And should have more torque for pulling loads.
I would not look for much torque from these small DC's.. The playa sand/dust ( ground resistance) will suck the power up fast. Fig, have the right set up.. Use the peddles for torque in start up and through sand dunes.. You will have better results by assisting the motor all the time.. Right now I'm working on putting a 12v roller set up on the road bike.. It should kick butt in 21st gear on the flat.. Going with 12v for one battery weight..

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Re: Bicycle question, three-wheelers??

Post by gyre » Tue Jul 03, 2012 8:11 pm

There are small batteries.

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Re: Bicycle question, three-wheelers??

Post by Shoeshine » Wed Jul 04, 2012 1:29 am

Wow, Thanks all.

(and sorry if I was snippy Gyre it was late).

Tons of good information here that will be of use to many besides myself I'm sure. I am properly chastened on the limits of my engineering knowledge.

My main thrust of looking to source w/ 12v was that it is what I already have, both battery and charging rig (solar and conventional). But looking over availible (and cheap/low cost) motors might seem to dictate that higher voltage would get me a much better cost to power ratio. The higher voltage motors seem to be much more common w/ possible exception of power chair rigs (have to investigate that) Wiring is not a problem and good point that a 24 or 36v charger is much cheaper than any step-up transformer I can googe-fu ATM. This of course would require another battery or two, but as I look further into it the batteries cost start to pale in comparison to some of the other possible componants.

@Canoe good to know about the cut-off voltage of the controllers. Also I like the idea of running a more complicated gearing system to make use of the higher RPM motors. The mechanical aspect is more where I am comfortable and lord know if you gear a motor down far enough a tiny one can pull a tank. (which is my goal with this project anyway)

anyway... Rock and roll...

and I'll make sure to report back as I test out various set-ups depending on the obtainium I come across.

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Re: Bicycle question, three-wheelers??

Post by Canoe » Wed Jul 04, 2012 5:15 am

Shoeshine wrote:...I like the idea of running a more complicated gearing system to make use of the higher RPM motors. The mechanical aspect is more where I am comfortable and lord know if you gear a motor down far enough a tiny one can pull a tank. (which is my goal with this project anyway)...
Great!
You should be able to handle gearing down to get a motor into its optimal power range and for pulling your load.
Rather popular for the higher-end stuff, are the larger of the brushless DC motors designed for the Remote Controled (model) aircraft crowd, greatly geared down. The youtube videos of the setups running are quite astounding as to their road speed, and the motor speed. You can hear the distinctive high whine of the motor, and from quite a distance in some of the videos.

Note that if you stay away from brushless motors you can get by with a fairly inexpensive controller, or even make your own.

As an e-bike for general use, I like the LiFePO batteries. But, 10ah costs a fair amount. So as you're not going over 5 mph, the heavier deep cycle lead-acid batteries start looking very interesting due to price/performance. FijJam posts reguarly about these batteries in the 100 ah range at http://eplaya.burningman.org/viewtopic. ... 20#p846132.

I haven't kept up much with advances in the past year, but prior to that I found that http://endless-sphere.com/forums/viewforum.php?f=28 tended to have the best information. Look around at their other forums.

And then there's things like belt-drive using timing belts instead of chains (and making your own sprockets (and gears), even out of plywood). The belts smooth out applied motor torque; then you can start pulsing the motor to save electrical power. Tons of ways of powering an application.
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