great bargain: entry level e-MTB

Reid Welch

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Nov 18, 2006
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Location
Miami, Florida
I'd buy this in a heartbeat if I needed another e-bike.

Shipping is included. $339
The stickers all peel off at will.



http://www.thesuperkids.com/20cue.html

It's got a simple, brushed gear reduction (Unite MY1018) motor driving the rear wheel through rugged, simple chain drive.

This general system, which I have in my own Currie Mongoose Cruiser, pedals as easily as any non-electric.
The motor drive freewheels at the hub so there's absolutely no degradation of pedal-ability.
It's the simplest, strongest, application of a side-drive motor to a bike.
The Unite motor costs $45 (from TNC Scooters) to replace if it breaks;
and it runs without groans or shudders from a simple cool-running controller, $40 to replace if it breaks.

This general system (non hub motor) has the advantage of allowing for a bulletproof bike wheel.
The hubs too are steel if they are like my bike's hubs.
No spoke breakages with this bike.


Whereas, my retro-bike is a hardtail with primitive front springer fork,
here you've got front and rear suspension, all in steel for strength.

You can put a better battery (NiMH) into that admittedly ugly box, for double the range.
You can paint that box a better color if you want. Note the easy reach to the power off-on switch--right there on the battery box.

You can enjoy this bike as-is, and upgrade the battery or even hot-rod the motor later on for 24-25mph level road operation.

It won't be a grade-A quality bike, but it's going to be rugged, strong and capable of jumping the rough stuff.
Set it up right and keep it clean and it will last forever.


Check it out? What do you think. I think it's almost a steel steal.

That electric blue color lights up in sunlight like nothing else.
My own electric blue Mongoose cruiser draws color-compliments all the time.

This is an all-steel bike; unless you must haul it upstairs you want an all-steel bike for rugged e-biking.

With its pedal-gearing you can go mountain biking.
The twenty pounds of lead will not add to the fun when you drain them, though.

The limitation is, the e-drive gearing is fixed, as is also true with all but Cyclone-type e-bikes and the neat, two-speed Crystalyte hub motors.

You can use this torquey e-drive for assist on grades
but not very battery-efficiently--unless you help it on those grades.

It will go 16 to 17mph on the level road. With 36V (the controller will take it), it'll go about 24mph.

It has plenty of torque to start you up at stoplights without pedaling;
that's the benefit offered by any gear motor.

If used as a city bike, put slick tread balloon tires on the thing;
knobby tires are poor for an ebike, and of no benefit on pavement;
only a detriment against rolling ease, handling and wet road-grip.

--the Bontrager Hank (2.25" wide) or Big Hank (2.5" wide) balloon slick is my personal tire choice for added comfort and great grip to wet or dry pavement, and for silent running and low rolling resistance.


I should be a bike salesman. Someone send me a commission check,
please?

:lol: :lol: :lol:
 
you make a very tempting point there! - this would be a great bike (with a higher Wattage motor and controller and a few batteries.)

I'm thinking it would be good as a second bike for short errands for those who have a main commuting ebike. :)

would a BMC / Kollmorgen motor fit as a straight swap?
 
No, those won't fit as a straight swap--well,
what's the gear motor used on the Cyclone bikes?

That could, I suppose, be easily adapted to the Currie's motor mounting plate
(which is simply steel plate--it is also the torque arm for the system).
The drive sprocket of the Unite motor is 11T, fixed to the shaft.
The Cyclone motor has a freewheeling 14T cog. So this'd up the gear ratio;
not a really-wanted thing to do unless you're on flat land,
and even then... not sure that higher gearing would be a help.

You can't change the Currie's -hub- freewheel cog (that one on the left side);
it is partly integral to the Currie's hub itself.

Someone should try this though--change up to a "better" motor.
What is to be gained is a bit higher efficiency.

Yet, I can go 25mph all day on my stock motor because it is now force cooled.

Running 25mph costs me about 800W.
Running 16.5mph costs only about 300W.
(these figures with the stock brushed motor)

The gearing-down of the motor in both the Unite and the Cyclone motors is, I suppose (have not checked) to a similar ratio.

The Unite does it without planetary gears, and proves that its armature-integral hardened steel pinion
against a single, larger gear, all in ball bearings, is
simpler and strong enough for the job, for it does not break on me,
not yet--and I overload it all the time.

And both motor systems must make probably a similar, inherent gear whine.

And the one motor costs $300 to replace in its entirety and the other, one-sixth of that.

Go stock for a while. Goose it to 36V.
But if you do 36V it and run the Unite too hard for too long at a stretch, it will burn out its armature windings, and then you're out $45 plus postage.

I have not compared the Cyclone motors to the Unite in terms of power output possibilities. But it does cost Watts no matter which to forge each mile added on top of 20mph.

The Unite is a "250W" output motor.
I'm probably asking it to give 500W to the rear tire when I'm burning down the road at 25mph.
Perhaps 250W or more of battery energy is going off as waste heat if my guesstimated numbers are anywhere near the reality.

Let me check that 25mph number now---I'll go out and make a short two-way run in still air and pin down the actual wattage consumed at that speed on a level, smooth road.
 
report: 800W seems about what 25mph costs the battery of my bike at 25mph.

It's hard to pin down exactly---I can't, because the Drain Brain gives instantaneous readings which fluctuate wildly, a hundred up, a hundred down.

I'll say conservatively then that 25mph costs 800W when running a force-cooled Unite MY1018 this way
on a nominal 36V system (40V of lipoly in fact).


fwiw.
 
For one hundred dollars more the same place will sell you this Aluminum hardtail version of the bike.




I show this because it makes clear how the Unite motor is attached,
and gives hints to those who might want to swap the motor system for another sort.
 
This is the model I'm probably going to buy before summer.
 
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