Help Me Choose a Motor -- I Found Some Great Ones
- Thread starter Beagle123
- Start date
TylerDurden
100 GW
I would do a stacked freewheel on the back:
1 cog/freewheel for motor drive
4-5 cog for pedals.
1 cog/freewheel for motor drive
4-5 cog for pedals.
Miles said:
The front hub i'm going to use at 10-25 mph range, but i'm going to pedal until 15 mph.
The rear hub i'm going to use at 3-6 mph range.
So both ranges are narrow enough for one gear each.
(Safe for example is quite happy at 0-10 mph wide range at the first(bottom) gear )
TylerDurdenI see only one chain at the photo.
Would you like use two chains at both side's of rear hub or at the same side ?
TylerDurden
100 GW
eP said:
Two chains, same side... like Randy.
(pic for example of dual freewheels)
TylerDurden said:eP said:
Two chains, same side... like Randy.
(pic for example of dual freewheels)
Maybe i'm blind yet but i see only one chain at the pic.
Do you know how to mount two freewheels at the same side ?
Now i'm thinking about left threaded adapter to right threaded freewheel clutch ( as you can find at pocket bike ).
There is in fact only one chain in that picture.
Actual product may vary from illustration.
Mounting a pair of freewheels would be as simple as dropping by your local machine shop, or doing it yourself if you're lucky enough to have the tools.
Actual product may vary from illustration.
Mounting a pair of freewheels would be as simple as dropping by your local machine shop, or doing it yourself if you're lucky enough to have the tools.
TylerDurden
100 GW
eP said:
I understand a bottom-bracket plug/cup can be used to extend the hub...
http://members.westnet.com.au/rjharrop/recumbents/retro-direct/Retro-Direct2.htm
Beagle123
10 kW
OK so far we have these motors:
<a href="http://www.battlekits.com/robot_motors.htm">Mag Motors</a>
However, maytag says that the fried these motors because their brushes are soft.
<a href="https://www.unitedhobbies.com/UNITEDHOBBIES/store/comersus_viewItem.asp?idProduct=5142">EPs motor</a>
This motor looks too small to disapate the heat to me.
<a href="http://tncscooters.com/product.php?sku=106170"> Cheap Unite Motor</a>
This is a basic motor, should do the job, but I don't trust their efficiency numbers. Sure these is better quality out there.
<a href="http://www.thesuperkids.com/600wahspsuto.html">Fetcher's brushless 1000W</a>
Thiis motor is looking really good to me right now. I can't think of a shortcoming except that I might be buying an expensive 35 amp controller, and want an upgrade.
Am I missing any good motors?
You never hear anything about this motor:
<a href="http://www.agnimotors.com/home/index.php?option=com_frontpage&Itemid">ANGI motor</a>
They have a video where it powers a boat that goes really fast. Its impressive. But I emailed the company, and they cost $1400 (if I remember correctly.)
<a href="http://www.battlekits.com/robot_motors.htm">Mag Motors</a>
However, maytag says that the fried these motors because their brushes are soft.
<a href="https://www.unitedhobbies.com/UNITEDHOBBIES/store/comersus_viewItem.asp?idProduct=5142">EPs motor</a>
This motor looks too small to disapate the heat to me.
<a href="http://tncscooters.com/product.php?sku=106170"> Cheap Unite Motor</a>
This is a basic motor, should do the job, but I don't trust their efficiency numbers. Sure these is better quality out there.
<a href="http://www.thesuperkids.com/600wahspsuto.html">Fetcher's brushless 1000W</a>
Thiis motor is looking really good to me right now. I can't think of a shortcoming except that I might be buying an expensive 35 amp controller, and want an upgrade.
Am I missing any good motors?
You never hear anything about this motor:
<a href="http://www.agnimotors.com/home/index.php?option=com_frontpage&Itemid">ANGI motor</a>
They have a video where it powers a boat that goes really fast. Its impressive. But I emailed the company, and they cost $1400 (if I remember correctly.)
Beagle123
10 kW
Miles said:
Do you have any numbers on this CVT? I know when I got it I was dissapointed when I tried to spin it with my hand, and it took some effort just to move it.
How bad to you think it is? 70%? 80%?
Beagle123 said:
I guess it will depend on what you're putting through it, and what the effective pulley diameters are, at a given ratio. I don't have any efficiency figures. Once you have a motor, try it out - see how much power it soaks up...
TylerDurden
100 GW
Beagle123 said:
You might try using a clamp-on ammeter when you run the CVT with your drill. Calculate the watts needed just to move the thing, then estimate the frictional losses by the belts.
Meters are cheap if you don't have one. Any excuse to buy more tools is a good thing.
The Mars brushless motor is also worth considering, but it's a big sucker.
I've generally assumed that the friction losses in a belt driven CVT would cancel out the advantages of having variable gearing. I don't remember anyone actually trying it so I can't say that's the case.
Tyler's suggetion is a good one. If you could measure the no-load power consumption of a motor, then measure the power consumption going through the CVT with no load on the output, you could find out how much power will be wasted by the CVT.
If it's 10 or 20 watts, then no big deal. If it's 150 watts, then it's going to waste a lot of battery juice.
The amount of power wasted will increase with load, but not necessarily linearly.
I've generally assumed that the friction losses in a belt driven CVT would cancel out the advantages of having variable gearing. I don't remember anyone actually trying it so I can't say that's the case.
Tyler's suggetion is a good one. If you could measure the no-load power consumption of a motor, then measure the power consumption going through the CVT with no load on the output, you could find out how much power will be wasted by the CVT.
If it's 10 or 20 watts, then no big deal. If it's 150 watts, then it's going to waste a lot of battery juice.
The amount of power wasted will increase with load, but not necessarily linearly.
TylerDurden
100 GW
Another thought:
Measure with the belt on and the belt off, to get a VERY rough idea of the belt losses.
You might need to drive the pulleys separately (sans belt) and combine their measurements, to isolate just the belt .
Measure with the belt on and the belt off, to get a VERY rough idea of the belt losses.
You might need to drive the pulleys separately (sans belt) and combine their measurements, to isolate just the belt .
Beagle123
10 kW
I did notice that the drill was going considerably slower when attached to the CVT. Its says 2700rpm on the side of it, and when attached to the CVT I estimate its going about 1500 RPMs.
I'm seriously considering the Mars motor. It looks great, and I like the shaft because I should be able to attach a coupling to it, but I can't find any numbers on it. They haven't published anything on it.
