Voicecoil's red, fully rigid commuter

[Mark_A_W]

You can get a Cycle Analyst from Getadirtbike (and batteries), and you can also get a CA from http://www.ev-power.com.au/-Bike-hub-motors-.html

How was your holiday?


And I'm interested to see how the Bafang goes at 72v 28amps Knuckles turned his gears to peanut butter

 

[Ben]

I'm also very interested. I'm thinking about getting a front wheel Bafang and running it on 48V 28A.

You get the option of choosing which speed/rim size hub you want, right?

Also, if you're still thinking about the 10Ah Headway cells, there appears to be some quality control issues and overall badness (not sure about Getadirtbike's as they are different cells).

 

[voicecoils]

You can get a Cycle Analyst from Getadirtbike (and batteries), and you can also get a CA from http://www.ev-power.com.au/-Bike-hub-motors-.html

How was your holiday?

And I'm interested to see how the Bafang goes at 72v 28amps Knuckles turned his gears to peanut butter

Have you received your battery pack from getadirtbike?

If I order ebike.ca's custom length spokes I'll just get the CA from them. Otherwise I'll get in touch with getadirtbike for sure.

Holiday was great! Nearly 4k km's of driving all up with side trips. Took lots of photos, one's attached.

I'm hoping Knuckles problem was his friends grabbing brakes and throttle at the same time, which is what he said. I'm way behind in E-S reading, so I have not heard the latest. The gears may shred anyways though. Perhaps I should take one out and measure it up before running it incase I need to source a local replacement or metal equivalent.

 

[voicecoils]

I'm also very interested. I'm thinking about getting a front wheel Bafang and running it on 48V 28A.

You get the option of choosing which speed/rim size hub you want, right?

Also, if you're still thinking about the 10Ah Headway cells, there appears to be some quality control issues and overall badness (not sure about Getadirtbike's as they are different cells).

Keywin is a nice guy to deal with and re-sent my package at least once due to customs issues on his end. So I recommend him on that front. He doesn't always answer technical questions though. Or mine at least. I was able to confirm with him that he was sending me a motor suitable for a 26" wheel, but that's as far as I could get. You might have better luck.

I haven't ordered any batteries yet, thanks for the heads up. Just keeping up with the lifepo4-purchase groups messages has been a struggle. I was under the impression that getadirtbike was using headway cells, some lion, some lifepo4.

 

[Mark_A_W]

Yes, Getadirtbike's packs are headway cells.

No, mine hasn't arrived yet.


My brother's pack is having some BMS tripping issues. We are going to try it on my bike. Getadirtbike is helping us and has already offered to order a replacement, if it is a finicky BMS, rather than a controller/BMS compatibility issue (it did work fine for a month). It is possible there is a fault and the BMS is doing what it is supposed to, checking on my bike will help sort that out.

The group buy reads like a total disaster area to me....

 

[Mark_A_W]

FYI, my Brother's Headway pack seems to work fine on my bike.

I don't think the battery is the problem, but will continue testing.

Mark

 

[voicecoils]

Yes, Getadirtbike's packs are headway cells.

No, mine hasn't arrived yet.

The group buy reads like a total disaster area to me....

I'm in email contact with John @ emtb now. I'll get my spokes and CA from him, perhaps batteries too, we'll see.

group-buy is quite a read. I've asked an eBay lifepo4 seller 'green safe packs' about a 72v 10a pack, the response is $800USD + $150USD shipping. Or $880 + $150 for two 36V packs. Waiting to hear from "ping" as well.

 

[Mark_A_W]

Where from and how much were the single cell chargers?

 

[nomad85]

I plan to stay a cyclist first, ebiker second. I suspect your in a similar situation. I don't understand $100 bikes with $3k of ebike kit on them. Nice to see a few decent bikes around.

I took the same approach. I am a biker first but I love my motor Even with my battery on board, but power off I can still lead most of the 20-23 mile saturday ride with my father and his road biking friends, I am noticably slower on the larger hills though, but I make it up. 14.1 avg speed 15-17pmh on flats with moderate pedalling.
I get 28-30mph on flats with my motor(407) and 32 if I pedal pretty hard. I get about 24-26 mph up most hills, 18-22 mph(depending on length of the hill) up the larger 10-11% grades with pedalling. I just got some torque arms and but I havent installed them yet. I have an 11t high gear that lets me pedal at top speed.

 

[voicecoils]

Where from and how much were the single cell chargers?

AUD$170 for 12 single cell chargers inc shipping. They are USD$9.8 each if more then 10 are ordered from http://www.voltphreaks.com/ssl/catalog/product_info.php?cPath=1_23&products_id=28

EDIT, looks like the price went up a buck, now USD$10.8 each if 10 or more are ordered. Some serious markup there....

 

[voicecoils]

I get 28-30mph on flats with my motor(407) and 32 if I pedal pretty hard. I get about 24-26 mph up most hills, 18-22 mph(depending on length of the hill) up the larger 10-11% grades with pedalling. I just got some torque arms and but I havent installed them yet. I have an 11t high gear that lets me pedal at top speed.

Nice, your bike looks good. All the weight is in the rear, how does that feel handling wise?

 

[voicecoils]

Large photo of bike and components laid out (3mb)]
Items received to date:
Spokes
spoke nipples
cycle analyst (stand alone)
thumb and twist throttle
72v 28a ecrazyman controller
48v 8a power supply
bafang pmgr in the dropouts
avid bb7 mech disc brake (front in box, rear installed)

Waiting on:
Batteries
cetmarack
connectors and wiring (and fuses/breakers)
controller mods

[edit] Laced up the hubmotor. As you can see, spokes are too long with the 1-cross pattern. Spokes are flush with nipple heads but still quite loose/bendy. After unlacing the leading spokes, and loosening the trailing spokes as much as possible, there's not room for a 2-cross lace. Hmm..
[youtube]Sb3qveouzaY[/youtube]
(youtube's own soundtrack...please excuse)

 

[Mark_A_W]

Spokes are the hardest part...mine are too short for instance.

It's pretty normal to build the wheel with a cross 1 - with most motors it's about the same angle as cross 3 (steeper sometimes).

It's also normal to have the spokes bend into the nipple, as you can't get the nipple to the right angle.


You could try filing the eyelets a tiny bit to allow the nipples to rotate more.

Mark

 

[voicecoils]

You could try filing the eyelets a tiny bit to allow the nipples to rotate more.
Mark

To enable me to do a 2 cross? With 1 cross they're too long. I'll try a few more things before I give up. Fortunately the pack of 40 14ga spokes/nipples (216mm) only cost $15 posted. If I get the 13ga spokes from ebike.ca, I'll make sure the length is correct!

 

[voicecoils]

I'm playing around with battery placement. I made some cardboard mockups, based on the dimensions given by getadirtbike at e-mtb.com.au

I was actually a bit surprised at how small they are. 36v 10ah lifepo4 packs, with the extra lump of cardboard representing BMS.

Any comments or suggestions on placement? All the ones I've tried don't seem to get in the way of peddling or steering.

"69"

along the top tube

width and clearance check

along the bottom tube

xyster style (my gf wasn't impressed with that one :wink: )


Rear rack or front rack are options too (when the racks arrive) but if I can get the batteries in the triangle it's probably best.

 

[Ypedal]

It's ok if the spokes stick out the nipples a bit ( You will have to cover this with many layers of tape, or in my case, a bead of hot glue, covered in tape, and more tape, gulp.. but the spokes have to be tight or you will have problems ) with a 1 cross it must be some close to hitting the point that the spokes are tight, once you get there 1 or 2 mm of threads goes a long way.

 

[voicecoils]

It's ok if the spokes stick out the nipples a bit ( You will have to cover this with many layers of tape, or in my case, a bead of hot glue, covered in tape, and more tape, gulp.. but the spokes have to be tight or you will have problems ) with a 1 cross it must be some close to hitting the point that the spokes are tight, once you get there 1 or 2 mm of threads goes a long way.

Cheers, I was hoping they'd start to firm up fast at the end. I'll have another go at lacing it up tonight after I pick up some #6 nipple washers and use knuckles lacing suggestions. Maybe http://veloplug.com/ are the trick?

What do you think of battery placements?

 

[Ypedal]

Gravity will want to bring the boxes down, so it's usually better to build a tray or some reinforcement for the frame tubes, then let the packs rest into them..

VELCRO !!! *( the wide 2" stuff is great , wallmart , arts and crafts places, sewing supplies, etc..!!! :wink: )

 

[Zoot Katz]

Cheers, I was hoping they'd start to firm up fast at the end. I'll have another go at lacing it up tonight after I pick up some #6 nipple washers and use knuckles lacing suggestions. Maybe http://veloplug.com/ are the trick?

Well. I use a die grinder to knock down extra spoke length before taping a rim. Good end nippers and/or narrow flat file work too.
Stretchy rubber rim strips can shift too easily leaving the spoke recess exposed for the innertube to find its way in and burst. The Veloplugs would prevent that but so does cloth tape and the correctly sized plastic stuff.
Old style cloth rim strips resembled flat rope and are still best for absorbing heat generated by prolonged braking.

What do you think of battery placements?

I think you should keep the wires long until you've tried the various configurations on the road with real batteries

 

[voicecoils]

Gravity will want to bring the boxes down, so it's usually better to build a tray or some reinforcement for the frame tubes, then let the packs rest into them

I'm with you on that one. I promise I won't stick the real packs on with sticky tape

 

[voicecoils]

I think you should keep the wires long until you've tried the various configurations on the road with real batteries

Cool, I won't be cutting any leads till I'm happy with the mounting configuration

 

[voicecoils]

some bench testing success! I tried out my 48v 8a powersupply with the Cycle Analyst and no mods to the ecrazyman controller first. The CA lit up, and the controller gave me the 8 blinks indicating LVC. Then I soldered a 15k ohm 1/2 watt resistor to R3 on the ecrazyman controller and here was the result:

[youtube]GZVYPen6tR4[/youtube]
(my girlfriend is playing MarioKart in the background )

I was expecting no-load speed to be a bit higher. Perhaps I will mount the stand alone CA's magnet and see what the speed is. (just need to figure out how to adjust the "wheel" diameter.

Controller mod: 62v (originally) modded down to 42v LVC

 

[Mark_A_W]

Yes, please mount the magnet. I'm dead keen to know the freewheel speed at 48v.

You won't need to adjust the CA wheel diameter, at least for this test, it's close enough to a standard 26" wheel+tyre. My CA read the same as my other speedo with the default settings.

Mark

 

[voicecoils]

Yes, please mount the magnet. I'm dead keen to know the freewheel speed at 48v.

You won't need to adjust the CA wheel diameter, at least for this test, it's close enough to a standard 26" wheel+tyre. My CA read the same as my other speedo with the default settings.

Mark

Using my 48v power supply the CA reads:

39.3 km/hr
51 Volts
37 Watts unloaded (.73 A)

 

[Mark_A_W]

Thanks.

For comparison, my setup gets 46km/h at 54v.

And I just tried it at 65v Freewheel speed is 56km/h. With some pedalling I can hold ~45km/h pretty easily.

If the controller holds out (I'll replace the 63v caps), I'm upping the current from 18amps to ~28amps.


Your setup sounds like it needs 72v