Ebike "The Resurrection"

[doc007]

Well guys, this well overdue build is coming back from the dead. (http://www.endless-sphere.com/forums/viewtopic.php?f=3&t=19968)


One major limitation I was trying to overcome was the dropout design:

I originally thought I might be able to get away with using an angle grinder to cut an "L" shape, utilizing only 2 of the 4 original attachment points. Unfortunately, a mechanic friend said it might put too much stress on those 2 points rather than spreading any forces along the 4 points. I finally settled on doing the design the right way by duplicating the original dropout. The dropouts will now look something close to this:

Each dropout will be hand milled from 4" x 4" x 1/2" Stainless steel plates. The plates were bought from onlinemetals.com. Their service was great; very fast and efficient. It was also the cheapest price I could find online. I would buy from them again without any hesitation. I will post some pics of the dropouts when they are done.

I also went ahead and bought a rear motor. I decided to go with a 9x7 wind motor (ebikekit.com) in a 26" rim. I'm not sure what the brand of the motor is but it looks similar to a 9c or a MXUS. The wire coming out from the axle terminates with a 3 prong plug similar to this:

I will have to cut this wire and figure out which combo of phase and hall wires will work to run the motor. If anyone has done this to this motor please let me know. I haven't found any specific wiring info in regard to the newer ebikekit.com motors.

I have yet to buy a controller and batteries.
What type of controller and battery set-up do you guys think I should be going for?

Although I have been on the forums for a while now, I admit I am still very much a newb. After-all, this is my first build. :?

These are the riding specs I am shooting for:
1) Ability to do a 12 mile trip or 24 mile round trip.
2) Speed 30-40mph
3) Potential wheelies

These are the misc. specs I am shooting for:
4) Super simple charging (ideally it would be plug it and forget it, but I don't think it's that simple to achieve with LiPO and without spending a lot of $$$)
5) Clean and stealthy build

Let me know what you guys think.
Any help and advice you guys can offer would be greatly appreciated.

 

[GMUseless]

Killer bike!

I was lucky with my Kona removable dropouts in that they would accomodate my MAC 6T axle without much problem. I did however pretty much permanenly attach them to the wheel, and I remove the wheel by removing the screws that hold the dropuouts in place.

Which brings up a question: if you are designing new dropouts to also function as torque plates, why not go ahead and fully enclose the axle. Can't you slide those onto the wheel, tighten, then mount the dropouts/wheel assembly to the bike via those 4 screws? It looks like your current design will still be prone to spreading. I'm not a metal expert..so this is just a casual observation / quiestion.

As far as controllers, the Lyen Infenion controllers are a good match for those motors. I've got a Lyen 12Fet that I run a 9C 2810 on at 18S lipo, and it works great.

At 30-40 mph you should plan something like 45 -55 wh/mile, which can vary signifcantly on wind, grade, etc. When trying to figure range, don't forget you don't get to use the full aH on the label for LiPo. That is, for longevity and safety you're typically only using 70-80% of the capacity. 18S Lipo, 50 wh/mile, 80% capacity, 10 ah, gets you 11.5 miles. If you slow it down to 30, you might get more like 35 wh/mile, which would get you closer to 16.5 miles.

I'm a big LiPo fan. But it takes more work, especially sourcing from Hobbyking. LiPo is a hobby in itself, not buy and forget. But, it's got some nice advantages like desnity, and it can be more modular and configurable...and can be worked into a more stealthy build. If you need plug and forget and don't want to be keeping up with the battery on a cell by cell basis...you might want to consider something else. If you do go LiPo, a good place to start is at Method's Methtek.com. His protection kits will get you about as close to plug and play as you can get.

If you go Lipo, you'll probably be better off sourcing things from multiple places. You'll find better deals / better selection elsewhere on certain pieces like charges, connectors, wire, power supplies, etc. I use Hobbyking for pretty much LiPo only.

 

[motomech]

Totally kwel build, but i think you might have gotten the proverbial "cart in front of the horse", which is to say, "where are the batteries going to go?".
Frankly, To get the capacity and C rate[ability to discharge Amps at a high rate]you would need quite a bit of LiCoNi battery and it is neither modular nor configurable.
That leaves Lipo or A123 cells in custom packs{$$$}.
It seems to me, that Lipo is going to be the only viable option for you. You will need to place a few bricks here and a few there, for instance, a couple of 8 mAh bricks under the frt. down tube and a couple on the steering[fork]mounts.
It would take some time and money, but perhaps using the new Zippy Compact 7S 8Ah bricks and the Hyperion 1420i, you could build a relatively simple "plug and play" 14S[60V]2 or 3P system that would do the rest of the build justice.

Or do something like this;

http://endless-sphere.com/forums/viewtopic.php?f=3&t=41417

 

[GMUseless]

Hahahaha. I'd been PM'n back and forth with doc. In fact, he encouraged me to go ahead and post that thread on my Kona so he could see what I did. Funny you referenced it...and since it's no where near as nice as the real talented guys here on ES produces!

But I think you are right...for off road, nothing beats the density of LiPo. You've just got to have the patience and willingness to care for it. It's almost like a pet. Once you own it, you can't really ignore it.

 

[doc007]

Killer bike!

Which brings up a question: if you are designing new dropouts to also function as torque plates, why not go ahead and fully enclose the axle. Can't you slide those onto the wheel, tighten, then mount the dropouts/wheel assembly to the bike via those 4 screws? It looks like your current design will still be prone to spreading. I'm not a metal expert..so this is just a casual observation / quiestion.

Hi GM! Im digging you're new build thread. It looks great!

I decided to opt out of fully enclosing the axle. I wanted to be able to change out the rear tire easily if I got a flat. Also the way I designed it, I will have 135mm between the dropouts which brings me to my next question:

What type of freewheel should I get?

Im thinking of an 11t so I can pedal at speed http://www.amazon.com/SRAM-PG850-8-Speed-Cassette/dp/B003WOQ5DM/ref=pd_sbs_sg_3
will this fit?

 

[GMUseless]

What type of freewheel should I get?

Im thinking of an 11t so I can pedal at speed http://www.amazon.com/SRAM-PG850-8-Speed-Cassette/dp/B003WOQ5DM/ref=pd_sbs_sg_3
will this fit?

Sadly, that won't work. AFAIK, all of the common hubmotors utilize threaded screw-on freewheels. So you can't use one of the more modern splined types like the one you've posted. Also, you're going to be space limited fitting a hub into a 135 mm dropout...so often a 7-speed is all you can fit without trying to bend the rear dropouts (not good for alluminum)

Anyway, for the threaded freewheels you've basically got two choices. DNP makes a craptastic 7 speed 11T that many of us use...I've got them on all of my ebikes. You can get those at most of the eBike vendors. I got mine from both eBikes.CA, and MethTek.com. Expect some noise, and clicks. But, I have't heard of anyone reporting the dreaded lockups causing the pedals to starting autopumping and at WOT.

You're other option is to track down the now discontinued mega-range Shimano 7 speed 11T freewheels. I hear these are relatively excellent, but hard to find. They occasionaly pop up on eBay.

 

[doc007]

Totally kwel build, but i think you might have gotten the proverbial "cart in front of the horse", which is to say, "where are the batteries going to go?".
Frankly, To get the capacity and C rate[ability to discharge Amps at a high rate]you would need quite a bit of LiCoNi battery and it is neither modular nor configurable.
That leaves Lipo or A123 cells in custom packs{$$$}.
It seems to me, that Lipo is going to be the only viable option for you. You will need to place a few bricks here and a few there, for instance, a couple of 8 mAh bricks under the frt. down tube and a couple on the steering[fork]mounts.

Great question! The battery issue has been a real pain in the butt! I really wish I had some nice triangle space like the DH comps. I was thinking about mounting along the downtube. I tried to do a fitment test with 6S packs, but the pedals hit the packs:

Now im considering getting 4s packs which are slightly smaller but more importantly, ~$100 cheaper. I made some models of the packs, to figure out the best placement for them. I kind of want to steer clear of the handlebar/fork mount if I can.

Im thinking of doing something like this:

OR

I do like how GM used the DVD case. It definitely helps the stealth factor which is something I am trying to achieve. In either case I need to be worried about the front fork hitting the LIPO when turning or the bottom wheel hitting the case under compression.

 

[doc007]

Here are the mock-up packs I made:

Now let's see how I can fit them on the frame! :?

 

[GMUseless]

That's what Fechter calls CAD: Cardboard Aided Design.

 

[doc007]

lol that's what I call a Pain in the ASS. Measuring, cutting, scoring, folding, taping 10 of those batts was a b*tch. I sure wish I had a laser cutter.

Here is one version:

Might look ok with a case on it.

I plan to run the controller (25cm x 12cm x 6cm) along the bottom tube (under the batteries). Anyone else have any ideas on battery/controller placement?

 

[doc007]

I think this is what my predicted output will be for this ride:

 

[cassschr1]

I use 2" styrofoam for mocking up. 2"=50mm

 

[doc007]

Nice, I tried the white styrofoam but it made a huge mess. I guess the blue or the pink stuff would be a lot cleaner but I didnt have any on hand. Next up, is the mock-up of the controller:

http://i49.tinypic.com/2vjtycw.jpg

Controller comes in 3 weeks, hopefully less. It's a beast in size and I guess power (15x 4410 fet, 50A), but I think that's very subjective considering some of the crazy builds I've seen here on ES.

 

[doc007]

So I was able to rearrange the "lipo packs" for easier fitting and hopefully wiring. It will be a close fit but I think it will work. Here is a pic (red line denotes end of travel, orange arrow denotes direction of travel):

I plan on making a LARGE purchase from HK. I want to make sure I get it right in one shot. So far on the list is:

10x Turnigy 5000mAh 4S1P 14.8v 20C
?? Turnigy Pure-Silicone Wire 10AWG (1mtr) BLACK
?? Turnigy Pure-Silicone Wire 10AWG (1mtr) RED
?? 3.5mm 3 wire Bullet-connector for motor (5pairs/bag)

Wire mesh guard (length? size? --to keep it neat)
Heat shrink (length? size? --to keep it neat)
Wire (length? size?, need --for wiring phase, halls, and batteries)
Temperature sensor (model? --make sure my hub doesn't overheat)
Cell checker (model? --make sure cells are balanced)

I need some help filling in the blanks. Also, if I'm forgetting anything let me know.

 

[Ykick]

I love the CellLog 8S which records a log file that can be viewed later. For those type meters and chargers I generally look at EP Buddy but if you're doing a HK order it might make sense to grab an 8S along with your batteries.

Can't help much about shrink sizes as every installation is different but you can always find that stuff domestically. Looking good...

 

[GMUseless]

Looks pretty good...but Ive got a few things to think about.

Generally, all the items on a Hobby King must come from the same warehouse. In the US, it's much cheaper and quicker to select batteries available in the US warehouse. And, most of the accesories aren't usually stocked in the US....so once you add your batteries, you won't be able to add the other items. In that case, it's cheaper and easier to deal with someone else. We use Hobby King for cheap / huge selection of LiPo. They aren't known for great customer service.

Make sure to order extra packs to allocate for duds. Many report between 10-15% bad quality rates with HK. But still cheaper despite this.

I don't think the bullet conectors are right. You want 4mm bullets to match to those on your batteries, and I prefer them in pairs...not in three's. Not sure what your plan was there but, but threes aren't what you want for battery connections. Definately order something like 2x extra connectors and wire...you'll always want / need more.

10 awg is good for the main battery leads to the controller, but overkill for the connections in the harness. Plus, 10awg might be tough to fit into the bullet housings. I've used 12awg or 14awg for individual branches on my harnesses. Also, when I make harnesses, I usually add a couple of extra P taps for expansion.

If you use heat shrink, you'll need many sizes..get an assortment.There's always some connector or orther thing larger than your wire you're trying to wrap..so it's good to have all sorts of sizes.

I also like the Celllogs. I got mine from EP buddy...they've also got lots of the wiring accessories you might want.

Just make sure you have some way to meaure your LiPo the day it arrives. Hobby King's return policy is 24 hours from delivery to file a warranty claim.

 

[doc007]

UPDATE

Stainless steel arrived about a month back from Onlinemetals.com. It has been going into surgery since its arrival:

(Onlinemetals review: Would have been nice if they blew off the shavings with some compressed air before shipping. Overall, I was pretty happy with the speed of transport, price, and quality assurance. I would use their service again, if need be.)

After a bunch of this (including test fitting and measuring):

We finally got to this:

And eventually ended up with this (comparison to original dropouts located below and to the left, respectively):

Fits like a glove:

Dropouts done!! Big thanks to the good friends that helped make this turn from a chunky block of stainless steel to a piece of art. Your expertise in machining and CAD were vital to the successful completion of this operation!

 

[doc007]

While on the topic of surgery. The baby also got circumcised upon arrival:

Ouch! Had to do it though. Needed to figure out the wiring combo:

That's what I call a birds-nest. Hopefully, the battery pack doesn't suffer the same fate. The wiring above resulted in full-throttle (no pun intended, although I'm sure he would be proud). We believe that the combination of wires, at least for the halls, were correct since the motor didn't stutter during the full second we kept it hooked up (didn't want to blow the motor just yet). We suspect the resulting full throttle was due to a defective twist throttle. Time will tell. Replacement thumb throttle is on its way.

Big thanks to a fellow ES pal for helping me out with this part. Your experience was very helpful in making the diagnosis.

More to come! Stay tuned...

 

[doc007]

Discovered a little rubbing sound when I initially got the motor. When spinning the motor by hand you can hear a rubbing noise when the wheel reaches a certain section during rotation. I was worried it might be a wire rubbing.

[youtube]mFqGorTXYVo[/youtube]

Decided it would be best to pop it open before running power to it:

Interesting markings "8x7 +2" (I was told I was getting a 9x7 winding! ) I wonder how this motors performance will compare to a real 9x7 winding. I wonder if this is why Jason changed his mind about allowing me to open the motor at the last minute (http://www.endless-sphere.com/forums/viewtopic.php?f=3&t=42569). Anyway, here is a pic:

Here is some close-up pics to show the build quality:

(Some wire is exposed from the black wire sheathing on the center hall. The middle bare wire on the center hall looks a little kinked.)

(Some of the plating wasn't stuck together, but this is not where the noise it coming from)

(The culprit of the noise left its mark on the side plate. You can see the marking doesn't make a full circle. That explains the noise only when the wheel reaches a certain point in its rotation)

(The culprit was the white insulation covers. Their ends directly coincided with the location of the mark on the side plate. I wasn't worried about it since no real wire was rubbing. I figure the insulation will conform to a less resistant shape after some motor use.)

 

[doc007]

Can someone please confirm if the discharge wiring below is correct?

 

[sn0wchyld]

Can someone please confirm if the discharge wiring below is correct?

looks good to me mate.

 

[doc007]

Great, thanks for checking it over. Any ideas on how I can wire it up differently to clean it up? I plan on having 5 packs on each side of the bike mounted on this:

 

[sn0wchyld]

Great, thanks for checking it over. Any ideas on how I can wire it up differently to clean it up? I plan on having 5 packs on each side of the bike mounted on this:

one thing you can do is wire each individual pack in series, so you have two 20s 5ah packs, then parrallell these via the balance leads for easy balancing. that way you can plug pack 1's +ve directly into pack 2's -ve... pack 2's +ve to pack 3's -ve etc etc. saving yourself some wire, connectors and soldering. Not so great if you need to reconfigure the pack to charge though, and you really need to have your wits about you when you're connecting up the balance leads - as its easy to mess up and parallel the leads from pack two to pack one etc etc. but if you've got a 20s charging solution (bulk charger or a couple of 10s chargers in series) so you dont have to change your pack to charge then it works quite well... and saves you allot of time and space.

word of warning though... be very carefull if you wire it this way... as it's much easier to make a mistake than normal wiring, given it ends up looking very atypical with each pack plugged directly into the next.

 

[doc007]

Ok, cool so this is the same pack configuration as the previous diagram as above. Please confirm if the discharge wiring is correct here:

As an ALTERNATIVE:
So snowchyld, you were saying that maybe I can series up the left side and series up the right side. And then parallel them? This way I can keep all the wires in the same position even when I bulk charge? ..Let me know if I got this correct.

I can see how this can be messed up since this isnt the normal routine of plugging in the connectors. I wonder if I can make a bullet & wire housing of some sort, maybe something out of wood, so all I have to do is connect blocks together (one side has the bullets, other side has the loops of wires set up in series) on each side of the bike. Anyone have any experience with this?

 

[sn0wchyld]

Ok, cool so this is the same pack configuration as the previous diagram as above. Please confirm if the discharge wiring is correct here:

As an ALTERNATIVE:
So snowchyld, you were saying to maybe I can series up the left side and series up the right side. And then parallel them? This way I can keep all the wires in the same position even when I bulk charge? ..Let me know if I got this correct.

I can see how this can be messed up since this isnt the normal routine of plugging in the connectors. I wonder if I can make a bullet & wire housing of some sort, maybe something out of wood, so all I have to do is connect blocks together (one side has the bullets, other side has the loops of wires set up in series) on each side of the bike. Anyone have any experience with this?

yep, that's the same as you posted before.

here's what I was talking about...

the blue wires represent the balance wires
as you can see, by plugging the +ve of one directly into the -ve of the next, you save yourself a considerable amount of wire and connections - just 3 connectors are required (2 for the packs, 1 to go to your controller) vs the 16 needed for your setup. It also means less resistance in your lines, so less voltage sag too, which translates to greater efficiency!

You do however, need to be VERY careful when wiring it all up, as the potential exists to short out packs. So take your time, triple check everything, and triple check your triple check! :wink: Also, dont bother with this unless you intend to bulk charge!