First time builder - vpower.hk

jana

10 W
Joined
Jul 31, 2011
Messages
76
Location
Oslo, Norway
Hi

This is my first atempet to build an electric bike. I know there are a lot of fancy options out there, but i want this to be a low cost trial. I am planning to use a brushless rear hub motor from vpower.hk because of the low shipping to where I live (Norway). I will go for the rear wheel version. I will be converting a 97 Kona Kula MTB.

We have a lot of hills here and i wonder if I should go for 48V 800W or 1000W, or maybe something else?
800w: http://www.vpower.hk/product.php?id=52
1000w: http://www.vpower.hk/product.php?id=53
1000w is about 50 USD more.

Will the 100w0 have more torque at 20-30 mph? I think 25mph is my target speed - also uphill with some pedal assist.

For batteries I will go for 10 or 20 Ah RC batteries from hobbyking - but I will focus on the motor part first.

Any tips are welcome - espescially on the torque part!

Jan A
 
I bet the difference between 800 watt and 1000 watt kits is the controller.

so the 800 watt controller may be 15 amp
and the 1000 watt 20 amps

This is a guess, you could email and ask them, there is not much details on the web site.

It is a no brainer to go with the 1000 watt kit. You will be happier. Eventually you could change out to a better controller once you have the stuff figured out. As a new builder I think you will be happy with that kit. The price is right, but I really have no experience with that company.

LIPO batts from hobby king a good choice. I get about 25 mph on my mountain bike with 12 series
lipo, using a similar controller.
 
Go for more watts for a steep hill for sure. Likely the difference is the controller amps, and you will need it to be more. Climbing hills, pedal like hell if you have to, to keep the motor going at 15 mph / 25 kph. Below that most hubmotors make all the watts into heat, and then you fry stuff. If a really steep hill comes along and you can only go 10 mph, then oddly, you want to back off throttle, and keep pedaling your guts out.

Best bet for really steep hills, that is above 7-10% grades, is special motors with slower windings. These slow motors need much more volts to get to the same speed, but can stand going slower up steep hills without making heat. But you won't get those specialty motors from V power, at least not on a normal ebay auction.
 
Good luck and have a great time.

Hey, I heard that in the winter the canals in Norway freeze and people can ice skate from town to town. Is that true?

I've always like Norwegians (and have a wee bit of them in my genetics). They are by far the best winter athletes (except snowboard...we've got it there).
 
Ha ha - that is not enteirely correct. We do not have a lot of canals in Norway, but it is possible to ice skate between islands in the oslo-fjord.
Never done it myself though, I guess the tought of the ice breaking isn't so appealing to me. Prefer cross country skiing or snowboarding in the winter.

Thanks for your inputs,
I just ordered the kit with express shipping :)
 
HELLO, I ALSO ORDERED FROM V POWER.48-1000,26,REAR.PAYED ON 7/10, HE SHIPPED ON 7/27.MY MOTOR KIT IS NOW ZOOMING TO THE SUNNY WILD WEST OF ARIZONA (USA) BY SHIP.I SHOULD SEE IT IN 3 OR 4 WEEKS. FOR EXTRA $75 DOLLARS , I'D HAVE IT BY NOW. LIVE AND LEARN. DID YOU GET THE 48-1000 ? WHAT BATTERY ? THIS IS BUILD # 2 FOR ME. GOOD LUCK , DON
 
17 days to ship is not very impressive..
Auction sais: "Seller ships within 3 days after receiving cleared payment"

I received my paypal invoice with 74$ extra for shipping, but the text sais "Standard international shipping".
I have emailed them to change that to what it sais in the auction: "Express 3-7 work days"

Lets see how that goes..
 
Batteries...

So many choices..

Should I go for 2 of these:
"TURNIGY 5000mah 6s 20C LIPO PACK" for 41,82 USD a piece

or 2 of these:
"ZIPPY Flightmax 8000mAh 6S1P 30C " for 83,83 USD a piece

I guess there is a change i can get away with 2 of the 8000, if I go for 5000 I will probably need 2 more later to get enough range.
This will need more chargers and hassle.

What do you think?

My commute to work is 10 milesone way and a bit hilly - but I might be able to charge at work.
 
I use those same batteries (2 X six series right?) I use 4 to 5 AH to do my R/T commute of ten miles, So likely you will need 10AMPHours or more if you can not charge at work.
It would be nice to have a watt meter so you can see how much energy you use and understand the battery, If you are in the USA I noticed the 6series5800 AMP hour Turnigy are on sale- shipping from USA warehouse is cheap and it cost alot to ship from china
 
Thanks. I think I will start with 2 x 6s 8000mAh.

I will also buy some Polymax 5.5mm Gold Connectors that fit the connectors on the battery.
http://www.hobbyking.com/hobbyking/store/uh_viewitem.asp?idproduct=2087

I also need some wire - HK has a lot of silicone wire. What AWG should I use?
Is 12AWG = 4 mm2 0k? Will they fit in the connectors? What wire do you think is connected to the 8000mAh battery?

Will I be happy with 2 of these: BM-6 Cell Voltage Monitor 2-6S Lipo (New Version)
http://www.hobbyking.com/hobbycity/store/uh_viewitem.asp?idproduct=8927

watt meter: what can be recommended?
 
12 guage is fine for the power levels you are dealing with, but nothing wrong with going to 10.

The voltage monitors look good to me, though I haven't tried that one. The Cellog 8 is the favorite of most, if in stock. But that one is affordable, and has the beeper installed allready.
 
I am thinking of buying one (1KW motor) from them since they've got the lowest shipping to Sweden (where I am). Please let me know how it goes and if you'd be satisfied with the kit or not. Information about the kit or pictures highly appreciated!
 
It has arrived.

Rim is single walled wich I guess is not good.
The spokes are really loose. It can not be used like this.

I have a feeling that it might be best to open the hub up to make sure everything is lubed and tightened corectly.










 
Nothing much inside to lube. The bearings are the sealed kind.
But inside the motor is interesting. :)
As for the cheap rim and loose spokes, that's pretty standard for the less expensive kits. Snug up the spokes just a little bit, then ride it 20-50 miles. Then true the wheel, or have it trued. The spokes will stretch just a little bit at first, and by 100 miles should settle in and the wheel stay true.
 
Looks nice! Thanks for keeping us updated. How many days it took to arrive and which shipping did you use ?

I would open it only if you're sure you are not thinking of the warranty. Also give it a few tries before opening it. If it burns while its intact you can complain and ask for warranty. If things look fine then go ahead and open it. This way you get to fix the things that might go wrong in long time.
I got my ESC from Hobbyking and tried to open it and make sure it would last long (by making sure its heat sink won't touch wires in it). After the mod I connected the ESC to supply and after 40 seconds it smoked and obviously it was out of warranty. I didn't even got to have the motor to spin at all!

Please keep us updated by perhaps posting a video to see how loud the motors sounds and how it spins :cool:

Hope it all goes well
 
hi. thanks for you all being so interested. It is motivating. I bought the most expensive air shipping 70usd and I think it took less than a week. I haven't even ordered the batteries yet so it will take a while to get running. will give you some pictures and maybe a video when it finally happens.
 
jana said:
hi. thanks for you all being so interested. It is motivating. I bought the most expensive air shipping 70usd and I think it took less than a week. I haven't even ordered the batteries yet so it will take a while to get running. will give you some pictures and maybe a video when it finally happens.

Some good, free, advice- avoid a duct-tape battery.

Learn how to make a tab-welder and start to make some A123 packs.

Don't make the same mistake I did. Avoid expensive, heavy duct-tape packs made from weak round-cells.
 
I have the same motor (with extra cooling) that you have and i get 70km/t on 18 cell lipo pack from hobby king and i expect more when I upgrade to 21 cell, but if you plan to use the original controller a ping battery is recommended (safe and plug and play charging) + get a cycle analyst if you can afford one.
 
hi all, just received motor kit. It was a long wait. Payed on 7/10.Rim is also single wall.Rim is bent and dented.Will post more info next week when i lace in new rim. Gotta love these china ebay sellers. don c.
 
Hey there,

I also ordered from vpower.hk - I ordered a 24V 500W package but I'm not convinced that they have multiple products! Mine was drawing 30amps at 24V (=720W) and now I have upgraded the battery to 36V it's still drawing 30amps (around 1kW!) and everything is OK (it's current limited rather than power limited). The controller was stone cold after my 13.5 mile run but the motor was slightly warm (I end the journey with a 15% gradient!)

You might be interested in my other threads.. I've just taken the controller apart - you could see if it looks the same as yours?
http://endless-sphere.com/forums/viewtopic.php?f=3&t=32388

Your wheel looks the same as mine too (in this thread)
http://endless-sphere.com/forums/viewtopic.php?t=30405

I've yet to tighten my spokes but some of them were really loose on arrival.
 
Not much difference in the motors if they are the direct drive type, but the really low watt ones may have thinner wires leading in, while a 1000w one might have thicker ones. Might have. Once the motor has thicker wires, they can be run any wattage from 250w-3000w.

The controller is pretty much the only thing that would be different. How they specify wattage on controllers is still a mystery to me. One seller has a 72v 40 amp controller and calls it 1500w. True, at speed, the motor will tend to pull about 1500w. But the controller will put 3000w into the motor getting started. Another seller calls a similar controller 3000w. Which is right? beats me. I just learned to ask what the amp limit is set on for a controller.

30 amps is a pretty hot controller if your use is to be commuting efficeintly. Make sure your battery is up to providing 30 amps. 12s lipo would be great with that controller.
 
I'm running 3x 12AH SLA... They don't seem TOO upset (it's not a long period at 30Amps - perhaps a few seconds whilst pulling away until the back emf catches up and 3 or 4 minutes up a 15% gradient I have on my way home).. I can't justify binning them and upgrading to lipo just yet.. I'd consider LiFePO4 but a 36V, 20AH Ping would be a bit pricey.. But I'm going a bit off topic...
 
Its alive. Got my new rim laced in. Have installed all the parts on the recumbent tandem.Went out for a breakfast ride with the wife today.22 miles. max speed,35 mph. This thing flyes.Need to tweak the brakes a little.Rear hookworm 2.5 is a nice riding tire.This kit took 11 weeks to get here from china,but it seems it was worth the wait. don c.
 
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