48V 1000W rear hubmotor project (now with pictures)

[GrayKard]

I have no idea why. If I had my druthers, they'd all be the big picture, right in the post.

Sorry. You'll have to wear out your mouse on some of them.

Also noticed that, on my laptop, the pictures came out nice and bright and easy to see.

But on my older desk system with a CRT, they came out pretty dark, it's hard to see a lot of detail.

Anyone else having such problems? I can brighten them up, praise be to the gods of Print Shop Plus.

Cool, thanks for the pics, looks like it's turning out good.

To get the picture in the body of the post, click the inline button that appears after you attach an image. All the photos look fine on my laptop. They are plenty bright and I can see all the detail.

I was surprised at how much space there was on the side with the threads where you can mount a disc brake. You will need a very offset bracket to move the brake caliper over to the motor. But I don't see mounts on that bike so you have a bit of fabricating to do anyway.

Can't wait to hear how it performs.

 

[Little-Acorn]

I was surprised at how much space there was on the side with the threads where you can mount a disc brake. You will need a very offset bracket to move the brake caliper over to the motor. But I don't see mounts on that bike so you have a bit of fabricating to do anyway.

So was I. It comes from the motor being significantly narrower than the original bicycle hub it replaced, that plus the wheel being not very dished at all.

Yes, I'd imagine I've got to make some kind of extended bracket, either that or somehow move the disc away from the hub, which I'm not sure would be too smart. I've never worked on a disc brake on a bicycle, so I'll be starting from scratch, both in material and in knowledge.

Can't wait to hear how it performs.

Ditto!

 

[1of3]

Label on battery charger.

What's wrong with this picture?

220....?

my chi-knees kit looks about the same.....tire is shan 'dong' rubber co., controller looks same, wheel looks same, axle has wires pokin' outa otherside, same thumb, rack is different, pot metal brake handle sets.....
quiet, smooth and i can pop a wheelie.....whoopie....

 

[Icewrench]

Hi little acorn
I wonder if that freewheel might not be mounted on the wrong side of the motor?
All motors i`ve seen have the wiring coming out on the left side of the motor. But I have not seen em all.
Might watch for that when you finally power it up.... Good Luck

 

[Little-Acorn]

Label on battery charger.

What's wrong with this picture?

220....?

Bingo. I've written to Daoji at YXM about it.

, axle has wires pokin' outa otherside,

Hmmm?

I wonder if that freewheel might not be mounted on the wrong side of the motor?
All motors i`ve seen have the wiring coming out on the left side of the motor. But I have not seen em all.
Might watch for that when you finally power it up.... Good Luck

Ummm... uh oh.

Just checked a bunch of other pictures of various rear hubmotors... and 100% of them have the cables coming out the OPPOSITE side from the freewheel.

So, I just sent another note to Daoji at YXM.

This is getting interesting. I guess I'm going to find out if his communication after the sale, is as good as his communication before the sale is.

30mph going backward on a bicycle, hoo boy....! With the pedals beating me to death every step of the way. Wonder if I can get a helmet with a back-of-neck shield.

Great catch, guys. I missed that one completely.

 

[morph999]

Is that a fast bike? It looks super fast with those tires.

 

[morph999]

have you got your battery yet? are you going with lithium? Let us know how you like it. I've never heard of this company.

 

[docnjoj]

Bafangs have power wires coming out of the right side also.
otherDoc

 

[StudEbiker]

I'm a noob around here, but this looks exactly like a 9c motor to me. Am I wrong??

 

[Little-Acorn]

I'm a noob around here, but this looks exactly like a 9c motor to me. Am I wrong??

I've been wondering that. I've seen a motor that looks exactly like this, in several vendors' ads. Anybody know who manufactures it?

Morph, yes, I have a 48V 20Ah LiFePO4 battery on order from EP-Battery, an Ebay vendor in China. Some strange things happened to their Ebay ads a few days after I ordered, but I have been communicating with them about it, and they assure me the battery, BMS, and charger have been shipped on Nov. 5, coincidentally the same day that YXM shipped the hubmotor wheel kit. No sign of the battery yet, but it sometimes takes a while to ship from China to the U.S.

 

[Little-Acorn]

Well, I'm afraid I must tone down my praise for Daoji at YXM Corp. in China, the people I bought this hubmotor kit from.

They have been responding fairly promptly to my questions after the sale, which is good. I've heard some companies tend to ignore customers after they have their money. XYM Corp isn't one of those.

Now the bad news.

The tire on the wheel they sold me, has a pressure rating of 50 to 75 psi. I pumped it up to 65 psi to make it rideable, sort of splitting the difference between the highest allowable and lowest allowable pressures. Seemed to take it fine, tire became nice and firm as it should, so I put the valve cap on and went on to other things.

Now, two days later, I looked again and the tire was flat. Hmmm. Hooked up the pump and gave it a dozen strokes. I could hear the air hissing its way in, but the tire stayed flat.

Pulled the wheel (with the cables coming out of the right side of the motor, you CAN'T take the wheel all the way off since the cables go through the chain loop and there isn't one single plug you can unplug). Pushed the tire to the side, and found what you see in the picture here. There was NO tube-strip between the inner tube and the spoke holes. None, zero, nada. Since this is a double-wall rim, the holes are about 1/4" wide. When I pumped up the tire, the tube obviously bulged down into the holes, like a tube in an old Three Stooges film, and went bang. Glad I wasn't nearby when it happened, things like that make me angry.

This is the first flagrantly dumb thing I've seen Daoji at YXM Corp do. Well, maybe the second, if it turns out that the cluster is on the wrong side of the motor, jury is still out on that one.

Off to the bike shop to get a new tube, with an extended stem this time, and a fiber tube strip - rubber tube strips don't work for these double-wall rims with big spoke holes.

Ten points off for Daoji and YXM Corp. Time to drop them a little note.

 

[StudEbiker]

I'm a noob around here, but this looks exactly like a 9c motor to me. Am I wrong??

I've been wondering that. I've seen a motor that looks exactly like this, in several vendors' ads. Anybody know who manufactures it?

I believe this motor is made by Nine Continents, commonly called a 9C. If it is a 9C (and I'm pretty sure it is), it is the same motor sold by E-bikekit.com.

 

[morph999]

I had the same thing happen to me. I think it was my fault though. I used the rubber tube as the liner and after about a month, everything is fine. Actually, I put duck tape over the holes and then the rubber tube to line it and it's holding up really nicely.

 

[Little-Acorn]

I had the same thing happen to me. I think it was my fault though. I used the rubber tube as the liner and after about a month, everything is fine. Actually, I put duck tape over the holes and then the rubber tube to line it and it's holding up really nicely.

Morph, that kind of rubber works fine for single-wall rims, where there isn't really a "hole" for each spoke (the spoke head fills the hole). But on double-wall rims like these, that a lot of ebike places seem to be using for increased strength (a good thing), the whole is fairly big, and the air pressure in the tube (70psi) can force the rubber rim strip AND the tube, all the way through the hole, and BANG.

Your use of duct tape is a good idea. My LBS sold me a cloth tape with adhesive on one side, to use as a rim strip. I put it in this wheel, and also in an aero wheel on a tandem bike with 116psi tires that had gone bang the same way. After putting in this cloth adhesive rim strip, no more bangs!

 

[Little-Acorn]

Well, I had written to YXM Corp. in China, describing this hubmotor with the cabes coming out the same side as the 5-speed gear cluster, and asking if the gear cluster was on the wrong side (the other side has an identical-looking screw-on mount). They have replied, saying that the motor is definitely set up right: Both the cables and the gear cluster, should be on the right side.

The rest of the project is hanging fire as I wait for delivery of the 48V 20Ah LiFePO4 batter, BMS, and charger from EP-Battery in Hong Kong.

 

[Little-Acorn]

The rest of the project is hanging fire as I wait for delivery of the 48V 20Ah LiFePO4 battery, BMS, and charger from EP-Battery in Hong Kong.

And now it's not hanging fire any more. Today, Christmas Eve Day, the postman (looking very tired) delivered a heavy package, rather scrunched looking, with Chinese writing all over it. Inside was the 48V 20Ah LiFePO4 battery, a BMS with a big Vpower sticker on it, and a charger with another Vpower sticker.

Right out of the shipping box, the battery voltage measured 52.9V, occasionally showed 53A (digital Fluke multimeter). Plugged the battery into the charger and plugged it all in. There are two LEDs on the charger, one showed red and the other showed yellow. After about 10 minutes, the yellow one turned green. A few minutes after that, it turned yellow again, and kept cycling every minute or two. Unplugged everything, wondering if the battery were already charged, even after nearly 2 months at sea. Battery voltage at this point was around 57V.

Whipped out the tools, put a plywood pad on the back rack, connected up what was needed, bungeed the battery onto the back rack, and did thisanthat until I felt ready to try it out. Plugged in the thick black/red wires from the BMS to the conttroller, and the three lights on the thumb throttle came on brightly. Cables hanging all over the place, a few VERY bad solder joints, but I just hadda. Pressed the thumb throttle very gently, nothing. Pressed it further, still nothing. Pressed all the way, nada.

Noticed I still had a lot of black plastic electricians tape around the thumb throttle, left from when I was standing the bike on its handlebars and seat, installing electrical things. Some of it was wrapped around the red mystery button. Peeled it all off, tried the thumb throttle lightly, still nothing. Pressed the red mystery button, which went in, clicked, and then stayed most of the way in. Pressed the thumb throttle slightly, and the bike bumped forward and made a humming sound.

Making my own humming sound, I trundled it out into the driveway (this e-bike ain't light), checked over everything fearfully, straddled it, and pushed offf. Pedalled up to speed, pressed the thumb throttle, and it picked up nicely. Tooled around the neighborhood with wires etc. flapping in the breeze, then pulled onto a nearby straight stretch. Sun was well down by now, and I kept a lookout for low-flying reindeer. Pedalled from a standing start, then opened the throttle. Bike was up to 15-20 pretty quickly. Went down to the end of the street, slowed down for a U-turn, and came back. This time I held the throttle wide open. As I passed under a street light near the end, saw the speedometer saying 23.3 MPH.

Not as much as I expected, but which that disgracefully sloppy, slapdash installation I had done, I was grateful it ran at all. This answers one question: the power cables do indeed come out the correct side of the hubmotor, even if they have to go through the chain.

A VERY satisfying day. Put the bike away, after removing the battery (with all that weight so high, it falls over with the original kickstand, that's next on the wish list). Took the family to see San Diego's Christmas Card Lane, which is about 2 miles from my house.

Ho ho ho! My first e-bike is a reality! Needs some adjustments and a lot of cleaning up, but the eagle has landed!

Coupla questions for you gurus out there:

What do the LEDs mean on this 5A 48V VPower charger? One stayed red all the time I had it powered. The other started out yellow as it charged the battery for a bit, then started cycling between yellow and green, about once per minute. Does this mean the battery is fully charged?

Andd, should all three lights on the thumb throttle, be on at the same time? I thought the top one (green) meant the battery was fairly full; middle one (yellow) means it's starting to run out, and bottom one (red) means it is getting near exhausted. Do I have the wrong idea about this? What does it mean when all three are on at once, and staying that way?

Thanks, all!

 

[mwkeefer]

The yellow green toggle LEDS indicate balancing pulse / float voltage... it needs to balance, they should either go out or go permanent GREEN when fully charged and balanced... the red is normal the entire time, though it too may go green or turn out when the charge process is completed.

If your throttle is like my GoPed thumb, then all the lights should be on for a FULL pack (think bargraph with 3 segments)... as the pack voltage drops you will loose green, then amber then finally red will likely flash at you... you don't want to use that for a State of Charge (SOC) indicator though... get in the habit of knowing how much power you have used... do you have a watts up, a cycle analyst or an eagletree logger? They are very useful for SOC indicator as they track watt hours used and mah used. This is the best way to know the state of your packs (I'd leave my eagletree connected when charging to monitor loaded power).

Give yourself a week or two, you'll be asking us how to run your pack with another in series and how to mod your controller for 100v/50A = )_

Nice thread and welcome to the wonderful world of eBikes!

-Mike

 

[maesitos]

This time I held the throttle wide open. As I passed under a street light near the end, saw the speedometer saying 23.3 MPH.

So, do you mean 23.3mph is the top speed of your bike? If that is true, something is wrong because YXM CO. on his ebay add says that the max speed goes from 30mph to 37mph

Do you already know the range of a single charge?


I'm considering buying this kit if it's really a Nine Continents or at least it has the same features

PS: Sorry because of my English

 

[DAND214]

Nice build!
I have the same hub from SANNYKUNghttp://cgi.ebay.com/48V1000W-e-bike-motor-conversion-kit-w-disc-brake-26_W0QQitemZ190355060926QQcmdZViewItemQQptZCycling_Parts_Accessories?hash=item2c520bb8be on ebay only 24v 500w running on 48v, top speed is about 33 really pedalong. The hub is CONHIS MOTORS http://www.conhismotor.com/. I also say the wiring comes out the other side, mine does. I have at least 2000 miles on mine and it has been great. Also on the rim strip, you won't see too many from the china EBAYERS, I don't remember getting any on my Goldens or even my 9C. They might have the hub flipped just to center the hub.
I have mine on a MONGOOSE BLACKCOMB with a 8 seed freewheel which I can't really use. The big gear can't be used as the derailer hits the hub (big silver circle) I went to the halftwist throttle to get around the shifting problem the thumb throttle caused. As for the lights on the throttle, they will be on till you are just about totally out of power, they are really for SLA which show more drop than LiFepo4 does. If you turn the hub around you will need to change the wiring to get the right rotation. It will work fine this way and you moght have better luck tith axle bending this way.
Like I said I love mine, I have 6 ebikes ready to run 3 are golden, 1 is a 9C ( 2nd best) 1 bmc v1 and my Conhis, tht is my favorite. Get it straightened out and you will love it. I would expect more sped out of it though.
Enjoy you ride and have a HAPPY SAFE NEW YEAR.
Dan

 

[Little-Acorn]

Well, did some cleaning up, replaced a connector for the Hall-effect-sensor wires I had messed up, mounted the WattsUp Meter on the handlebars (ran the high-amperage 12ga drive wires all the way from the battery to the handlebars and back to the controller under the seat, not elegant but did not seem to affect performance), faired all Ebike wires under a shield mounted under the top tube. Bought a BUNCH of zip ties, both white and black to blend in with the bike's paint job (obvious tiewraps look tacky), folded all the too-long wires fairly neatly on top of the controller and ziptied them, got rid of the power-brake handles and put back the original brake levers that came on this Trek 7500, MUCH better braking. Two bungee cords holding the battery down (battery box is on next-to-build list), tucked in the charger cord, made everything nice and pretty. Also inflated the tires - rear from the 30psi I found it at (oops!) to 75, front to the 116psi it's rated for.

It was dark once again, so I ran it up and down the same street, this time the street light showed me 27mph. Pretty smooth, motor seemed a little torquey-er, though maybe that was the rear tire. This thing is starting to feel like a bike. Still pretty heavy, though, and that won't change.

Then today, I just got back from screwing around in the parking lot at work during lunch. That parking lot sure seems big when I'm walking across it after work, but got small pretty fast as e-bike speeds exceeded 25mph. The 11-32 7-speed freewheel from Pat at San Diego Electric Bike (619-216-8572) is a BIG help when accelerating to a top speed, before backing off to coast at full throttle and see if the bike holds that speed. Pat is a great guy, very knowledgeable on e-bikes, but laid back and humorous at the same time.

Got it up to 25mph in the parking lot (mostly empty during the Christmas holiday), and it seemed to be trying to accelerate further when I coasted with full throttle, but I had to back down to slow to turning speed. WattsUp meter told me the battery was putting out from 49.9 to 51 volts throughout, even when accelerating. Maximum amps I saw were 28A briefly, 27A more often during acceleration, then dropping off of course as I slowed (this bike has no regeneration capability, KISS).

Then took it over to a nearby street in an industrial area, which was pretty much empty during this holiday. It looked pretty much level to me, but I did runs in both directions just in case (they turned out to be nearly identical anyway, wind was across the road at an almost perfect right angle). Highest continuous speed I got out of it was 29.6 MPH, same in both directions. And it would frequently get up to that speed with no pedaling at all! Pretty awesome. When going that speed, I saw 23 Amps on the WattsUp Meter, and battery voltage of 49.7V. The lowest battery voltage I ever saw, while beating on it repeatedly, was 48.6V. I LOVE this 48V 20Ah LiFePO4 battery!!!

Biggest problem I'm now having, is that when the bike hits a bump, I hear a loud WHACK from behind me, soounds like the battery bouncing up and down on the plywood platform I put on the back rack. This happens even at lower speeds, like 8mph. I have some dense foam material from Walmart (camping ground pad, about 1/2" thick), and will cut a piece to go between battery and platform. Eventually I'll build a battery box, probably folding it out of 1/16" aluminum so it can mount the On/Off switch and fusible link, both of which aren't being used yet.

So far so good - a VERY cool ebike. Top speed nearly 30mph on level ground with no pedaling, even when hauling my sizeable posterior (I'm 265#) and the heavy battery and motor. I'll get some total weights soon.

Don't have any total-range figures yet. I want to fix that loud WHACK before taking it anyplace serious, public roads around here are often bumpy and broken, especially at the sides. Also want to mount the WattsUp meter properly, rubberbanding it to the handlebars like it is now is _so_ uncool.

 

[hillzofvalp]

I wish the pictures could be inserted in one post... with a image host like flickr. I don't mean to be an ass, but it's very difficult to go through any pictures here.