Popstar’s MXUS Dahon and MAC Fisher

[Popstar]

May 2013 update: I'm adding my 2nd build progress

1st Build: mxus folding bike
I’ve been riding this e-folder bike since August, but only now am getting around to making a build thread. I became interested in folding bikes and e-bikes after I moved into a house with a garage for the first time. My wife and I work at the same company campus and commute together, but she often gets stuck later than me, so having a folding bike in the trunk is a great way to avoid driving 2 cars or staying at work later than I need. On weekends, I will set out over the big set of hills into town and have made it 26 miles on 10ah with a bit of leg boost

I based many of my early decisions from RVD’s Dahon build: http://www.endless-sphere.com/forums/viewtopic.php?f=6&t=34958 .




Pieces (in order of installation)

2008 Dahon Speed D7 (Craigslist)
7 speed, Chromoly frame with v-brakes, 20” wheels
Rear dropout is ~130mm but can fit a hub motor with brute force
Be aware that there was a stem recall for 2008 Dahons. I got mine swapped for free at REI, per Dahon USA call center instructions
36V 12ah Headway battery ((BMSbattery, $405 including shipping and charger)
30-60A option, CNSFEDEX shipping, 240W charger
Geared MXUS kit (cellman, $290 w SAL shipping)
Built in 20” rim, high quality and very true
18A basic controller, thumb throttle with cruise, e-brakes, handlebar powers witch.
7speed 11t DNP freewheel had gear spacing issue that makes 6th gear skip every 4th tooth. Very annoying.
Sadly, cellman is not stocking these anymore. He told me a few months ago he would be offering a new e-assist motor in the "next few months"
Nord-lock washers (McMaster, $15)
These are great, and very important since the stretched dropouts would love to move the axle if these were not preventing it from loosening.
Schwalbe Marathon Racer HS 366 20” tires
Pumped up to 80psi with you eyes closed, you could trick yourself into thinking you were on a low-resistance road bike. (Tip: never close your eyes riding a folding bike!)
Harbor freight 11" X 7" X 4" “Aluminum” Case
This case is fancied up cardboard and aluminum strip, but it fits the headway cell perfectly with some padding and wood flooring samples (from home depot) for reinforcement and as screw in points for mounting to rack.
Recently I added a padlock by bending two door latch mounts 90° and JB WELD’ing them inside the box sticking out. It won’t stop a true thief, but makes it look legit.

Turnigy 130A Watt Meter (Hobbyking, $30)
The wide silicone wire on this thing does not fit well in Anderson connectors, which is very annoying.
Brooks Flyer (REI)
Enough is said about Brooks. They are are comfy. nuff said.
Mirrycle Bike Mirror
After riding down weaving country hill roads with this, I am surprised that bike mirrors are not more widely used by all bikes.
Shimano Mega 7 11-34T freewheel (bike co-op, $5!!!!!!)
I found this in the used grab-bin at a used LBS, and I went out and bought a lottery ticket afterwards. Compared to the DNP I was riding before, this thing makes the e-bike feel much lighter when not using throttle. The fact that my DNP had an unusable 6th cog adds to my excitement with the shimano. Now I can switch between the top 3 gears smoothly going up any hill.


Overall the bike has been a great experience learning bikes and how to utilize a garage workspace. The setup is as fast as I would want to go on a folding bike, about 18.5mph on flat with “for show” pedaling. Since it has cruise control, I keep the rear e-brake cutoff lever, but it is sad that these don’t at least come in v-brake compatible pull ratios!

2nd build planning
The folding dahon is great and serves its purpose of providing transport from the trunk of the car. Th eebike bug continues to nag me to build a full size ebike. Thus I am embarking soon on a e-bike build for my in-laws coming from china using a mid 90's Gary Fisher hardtail from craiglist. I am working with cellman to get some MACs and trying to see if his new 14S9P Samsung 18650 NCM triangle pack can fit my frame. The more I play with various e-bike parts and vendors, plus ES post reading, the more I realize that it is worthwhile to utilize sellers like cellman.

More to come in the coming weeks.

 

[motomech]

Nice review,

Yes, the MXUS is a little gem.
I burned out a hall sensor during a brain fade moment changing connectors, so I now run my frt. whl. motor sensorless on a Lyen Mini-Monster @ 22 Amps on 12S(46V). I'm probably pretty close to the max. power that can be run in warm weather. Sensorless, it's not too bad, needs about a half turn on the pedals to keep from stuttering when starting out. Every now and then, I'll screw up and not have enough momentum and have to stop and get re-set up by putting a pedal at the top of it's arc.
In my 26" wheeled mountain bike, I get 21 to 22 mph, no pedal and it will climb up to about 9% with help on my part. If there are no killer hills, it's about as good as an assist motor gets. very efficient!

I agree on the mirror, great little item.

 

[Popstar]

2nd Build: 90's Gary Fisher Hoo Koo E Koo with MAC and 14s9p NCM triangle pack

My kit arrived from cell_man. It only took six days since when paul said the battery would be finished building to when it was delivered in Portand, OR.

Em3EV parts:
10T MAC in 26" with upgraded phase wires
9FET 3077 with program cable
14s9p NCM triangle pack with triangle bag and charger
CA V2.3
Rev4 Torque Arm
DNP 11t 7 speed

I am still waiting for my schwalbe marathon tire and I need to replace canti brakes with v-brakes and switch to trigger shifters. Looking at the large twist throttle w 3 speed switch, I am thinking even with trigger shifters that access will be difficult.

Triangle Battery
This thing is beautifully constructed and feels quality. It fits easily inside of my 16.5" frame. I think this pack would fit nicely into some full suspension frames.



Here is the battery compared to my 36V 12ah Headway pack from BMS battery. It is about the same size, but the triangle pack has double the whrs!


Cell_man's charger has a I/O/II switch on it that he says will extend the NCM pack life by only charging to 90% and storing at 50%. I measured the 3 voltages from the charger and they seem matched to the case labeling. The battery was at 55V out of the shipping box.


50%:
90%:
100%:

MAC
Not much to say yet as haven't fired it up yet. It came disassembled such that the skinny but light wheel came in separate box (DHL battery service counts many boxes as 1 order). There was an instruction sheet for reassembly and it was easy. It looks like a small package of white grease was included with the bolts, and I am not sure if that needs to be added during assembly (as the gears already have goo on them) or if that is for future maintenance.
The hall wires are bound in shrink wrap, which I believe confused another ES noob confused with install. Putting it in shrink wrap is actually really helpful, as it makes threading nuts over the wire easier with less danger of damaging the pins. When I got my mxus from paul last summer it came with hall plug attached, and I had to remove the pins first, which made me afraid of bending them,



DNP 11t AKA "Shimano 11T we miss you and why are you gone?"
2nd strike against DNP quality: the largest cog is bent!

*Don't let this sound like a negative to em3ev or cell_man at all. When i ordered his website said the DNP 7spd were out of stock, but paul said he would try to scrounge one up and included it for free.
My first DNP last year has bad spacing between 5 and 6th gear, which makes the 6th gear not mesh with the chain and go cha-chunk-cha-chunk always. With that build I found a shimano 11t. I do not think I will be so lucky again. I may have to try to bend that gear straight and just not use 1st gear (who uses 1st gear on an electric bike anyway?)

One last picture to show what em3ev will do to get you the best deal:
View attachment 3
Paul said that with DHL battery shipping, it is cheaper if you cross the 20kg weight threshold. With the NCM pack being lighter than an A123 20ah I wasn't quite to 20kg. When I was unpacking my boxes I found all the items I ordered but had one box left. low and behold it was filled with cardboard sheets!

More to come about the new battery and my build as it comes together.

- Popstar

 

[Popstar]

10T MAC kit with 14s9P triangle batter on Gary Fisher build steps

The build is more or less complete, now that I made a battery locking solution at last. Here is the latest picture of it:


It certainly is not a unique or spectacular build compared to many of the impressive rigs being engineered on ES, but it feels great to me! It is something to be said of the quality of EM3ev’s kits such as this triangle batt that “they just work” without needing much real building skills.

So the changes and installed items since my last update:
1) The MAC installed in the dropouts very easily. Compared to my Dahon with the less than 135mm dropouts, it was nice not having to strong-arm the system in. I did have to file the paint off the inside of the dropouts to let the axle slide in. It is also a nice change from the MXUS with the MAC wires exiting on the opposite side from freewheel.

2) The ebikes.ca Rev4 rear torque arm went on nicely, although it took way longer than expected as I had to keep redoing the hoseclamps to not get in the way of the freewheel and rear derailer cable routing.

3) I upgraded the old cantilever brakes to V-brakes and redid the brake and shifter cable routing. The key general bike maintenance learning here was that using cheap cables and housing turns a nice bike into a bad bike. Do not use “Bell Universal cable kits” unless you have very shirt cable housing runs. My use of the triangle bag interfered with the top tube runs, so I went with cable housing the whole way. When I got real LBS-quality cables and housing everything worked nicely.

4) On the gear shifting front, I ended up going the route of many here and removed the front derailer. This happened by accident, as I stripped one of the limit screw holes trying to force the derailer to keep the chain on the large ring while I was still looking for quality cables. Removing the whole derailer makes the pedel area much clearer for batt bag and cable routing, plus it freed up the left handlebar to move the 7spd grip shift to that side. If by motor or bat ever dies and I need the other two front gears, I can still just push the rear derailer to loosen can and move chain to different front ring by hand.

5) I installed a “Axiom Journey” rear bike rack. This thing is much beefier than most rear racks I have seen and the connection design inspires much more confidence. Since the purpose of this build is as a grocery getter for my in-laws who don’t drive, I wanted a rack that could have many carrying options and capacity.

6) I purposely installed the rear rack mounted a little further back than level to allow enough room in front of the rack to attach the 9FET Infineon EB309 controller behind the seatpost, while still allowing the seat to go all the way down for when my mother-in-law rides the bike. I spray painted the controller black, and the pattern of smooth and ridged area actually matches the rack behind it.

7) I put on the front handlebars the twist throttle, both e-brake levers (they seem better quality than the wuxing levers that came with the MXUS kit which didn’t seem very good with v-brakes) and the cycle analyst. I also put on sawed-off Avenir Comfy Soft Grips, as their shape do seem better for longer riding than round grips. All the wire routing was funneled through an old bike tube down the downtube and up towards the controller.

8 ) Battery Harness for locking
Since this rig will be for going to a store and having to leave it outside while shopping, I needed a way to lock the triangle battery to the bike. I had dreams of learning to lay down fiberglass over a foam mold, but that seemed too ambitious to ever be done. I kept just thinking “if only cell_man had integrated a metal lanyard at the end of the battery that doesn’t extend to the peak of a triangle shape, then I could run a cable lock or padlock through that!” My next idea was whether I could just epoxy a metal U to the battery, but I didn’t want to damage or depend on the heat shrink wrapping. Finaly, while walking around Home Depot I came up with the idea tp I JB-weld a metal loop to a metal sheath wrapped around battery. My end purpose is to make it so any thief would see that tryig to steal it would likely result in damaging the battery in the process.

I started off by bending 2 metal sheets around the battery, and then bent the cornered outward to reduce the convex points.


Next, these were epoxied with JB weld togther around the battery such that they sheath could be freely slid onto the triangle battery. (I smoothed down all the edges and added plenty of end wrapping)


It was to this sheath that I then used JB WELD to attach a loop of bent sheet metal stripping such that one end kept the battery from sliding out of sheath, and the other end is extending farther out providing a locking loop.
View attachment 1

After curing, I rewrapped the whole thing again in electrical tape and duct tape. I also used some old road bike handlebar tape to pad the handle/locking loop


Now the battery can go in the EM3EV triangle bag (a little tighter), and a lock cable is looped around the harness, then routed back out the rear wire hole, around the stays, then up to the seat. I will get a padlock that will attach to the seat, as I intend to get a Brooks saddle soon, and this kills two birds with one stone protecting the battery and saddle at once.


Now we are good to go!

I have some ride observations that I will update later.

 

[Popstar]

Reserved pst spot for future ride observations, speeds attained, and controller/CA programming.

 

[sabongi]

Congrats on the build, looking good so far!

 

[pithy]

Nice clean build! Any comments on the battery pack so far? Are you running it at 22amps still? Does it get hot? I'm very curious about these batteries and how well they work.

 

[pwd]

I would also like to know what you think about the battery. That triangle pack looks like a great design.