First time builder / wanna critique my plans?

someguy

100 µW
Joined
Jan 14, 2013
Messages
7
Location
Colorado Springs, CO
Hello from Colorado Springs, Colorado!
I'd like to park my gas powered truck and start cycling to work 5 days a week (weather permitting). It's exactly a 28 mile round trip.

* Bike
2005 GT Avalanche 2.0 GT

* Requirements

* Simple to build/maintain
* Low maintenance
* Easy & safe charging
* Easy to pedal
* 30+ mile range:
- Outbound - 14 miles / 1000' descent along a trail or city streets w/ occasional minor hills
- Return - 14 miles / 1000' ascent on paved trail or city streets w/ largest hill of 10% grade for .6 miles

* Motor:
While I love the idea of a mid-drive, I think it's more work & time than I can afford right now. A hub motor seems to fit the bill for this build.

I'm liking cell_man's 500-1000W MAC hub motor kit $415 + shipping / China

The options I *think* I want:

* Motor
- 320 RPM @ 36V 8T
-- w/ upgraded phase wiring & temp sense

* Controller
- 12 FET 40A (36-72V IRFB4110)

* Rear Wheel
- 26" Alex wheel

* Throttle
- thumb throttle

* Brakes
- ebrakes

- End of options -

* Rear hub
7/8/9sp DNP 11T Freewheel $20 + shipping / China

* Torque Arms
Dr Bass $25 / Canada

* Cycle Analyst
CA3-DPS V3 Direct Plug $155.00 + shipping / Canada

* Charger
240W Fan Cooled, Aluminium Case Charger 43.8V 5A (12S LiFePO) $55.00 + shipping / China

* Charging situation
@ work - unknown as of yet - I'm assuming the answer is NO
@ home it will be in an attached garage w/ smoke detector.

* Batteries

I think I want 48V 20 Ah. These battery packs are under consideration (ordered most to least llikely):

*NOTE* I assume all free BMS & chargers are adequate at best and likely prone to failure.
I intend to purchase a Cycle Analyst ver2 or 3 and a charger. Maybe the free charger could be used at work.

cell_man $590 + shipping / China
38V 20Ah A123 Battery Pack
No charger
No BMS

Vpower $564 + shipping / China
20AH 48V LiFePO4
Free 6A charger
Free shipping (6 weeks)
OR
$168 7-14 days

Goasis Energy $659 + $38 shipping / USA
48V, 20AH LiFePO4 Battery
Free 3A Charger
Free Battery Management

BMS $369 + Shipping / China
48V20Ah Li-Ion NiCoMn
Free 4A charger

Ping $658 + shipping / China
48V 20 Ah
Free 2A charger

Conhismotor $395 + Shipping / China
8V 20AH LiFePO4 Battery
Free "fast" Charger
Free BMS
Free Bag

** I understand the reputation of conhismotor to be 'questionable' but I have seen at least one mention of a working
battery pack and some suggesting that they may try a battery purchase from this vendor.

* Battery notes
- The 38V pack from cell_man will fit into this frame rather well (w/ room left for controller) but...it's only 38V.....
- I really do not want a battery on a rack over the rear wheel.....
- Top speed is not as much of a concern as range.

These items I'm not entirely certain of:
* Motor winding for my requirements; is the 8T @ 48V the answer?
* Rear hub recommended gearing?
* Front chain ring?
* Throttle - I can't decide on the type. I think I want a thumb throttle but don't know that I'd much care for this one.
I had imagined the lever operating from side to side rather than up/down. That might interfere with the shifter though.....

So...what have I forgotten? Overlooked? Should I upgrade anything?

This thing is already over budget so if there were any dollars to be saved........

Any recommendations from the wise e-sages are very welcome. :) Thank you for your time.
 

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My just-started build is quite similar to your plan. However, concerning the cell_man 38V battery pack, are you sure 4 inches in width inside the triangle won't impede your pedaling?
 
very intersting topic, very similar to my build but I am planning LiPo. Just spent the last 2 hours reading about LiPo for ebikes, infomation overload!

Good luck with the project, I shall watch closely.
 
Can you pin point that 10% .6 mile climb so I can follow it with Google Earth. That hill will ask you for at least 25 amps from your battery and be expected to help pedal. You may want the CA set to get you 30 amps but check how hot the motor gets at the top. Google Earth gives us the altitude at the bottom and top of the hill then distance. Just say the street name between what two streets or longitude and latitude. Too bad LiFe batteries are so expensive. I would go with a 10t for that hill. Some may say the 12t. Seeing that hill may get the motor selection done.
 
RE: Work charging.
Gawd I've been blessed. Not only do they let me bring my bike into the office, I charge there too. I never asked permission to do either. Now, the bike itself is pretty damn obvious. I started bringing it in about 2 years before I electrified it. That's an important part of the story... The (TSA-like) building guards were already used to the freaky guy with a bike - but proper building credentials. Nothing to see here, I have the golden ticket.

Once they were used to me bringing a bike in, I started adding crap to the bike. Panniers. Lights. Wires. Lots of wires (oh at first they were for lights, and for motorcycle heated gloves...)

Consider following in this path. Maybe drive part of that 14 miles with bike on a rack, and "arrive on bike". Do this as you build. Maybe even show up with the bike, hub motor installed but non functional. "Oh that's a motor, but it's not hooked up". I did the same thing with my folding bike. I had the drive reduction mounted well before many other parts. It was the consequence of building slowly, but commuting every day. But, it ensured I didn't just show up one day with this freak-ass bike...
 
onlineaddy said:
My just-started build is quite similar to your plan. However, concerning the cell_man 38V battery pack, are you sure 4 inches in width inside the triangle won't impede your pedaling?
I think it will be close. I'll make a mock-up and try it.
 
drummerian said:
very intersting topic, very similar to my build but I am planning LiPo. Just spent the last 2 hours reading about LiPo for ebikes, infomation overload!
Good luck w/ the LiPo. I didn't feel qualified or ambitious enough to tangle with those bad boys. I want plug-n-play batteries. The price for LiPo however is no doubt very attractive.
 
CogHog said:
Can you pin point that 10% .6 mile climb so I can follow it with Google Earth.
It's Filmore hill

That hill will ask you for at least 25 amps from your battery and be expected to help pedal.
Pedal assist I can do! Truth be told I can go other routes too but this is the most direct. It's also a worst case scenario as the remainder of the hills are all probably < 7%.
 
MattyCiii said:
RE: Work charging.
Gawd I've been blessed. Not only do they let me bring my bike into the office, I charge there too.
The owner of our small manufacturing (approx 200 employee) company is actually an avid MTB rider and competes nationally. I haven't approached him yet on the subject as I don't really have it all worked out. Unfortunately he may not be the decision maker in this as it's a matter of safety at some level. I had thought to bring my own cord and a watt-meter and even offer to pay a 100% markup on the electricity. There are plenty of locations outside that the bike could safely be stored and charged.

Wires. Lots of wires (oh at first they were for lights, and for motorcycle heated gloves...)
Haha too funny.... I'll bear this in mind for certain.
 
someguy said:
CogHog said:
Can you pin point that 10% .6 mile climb so I can follow it with Google Earth.
It's Filmore hill

That hill will ask you for at least 25 amps from your battery and be expected to help pedal.
Pedal assist I can do! Truth be told I can go other routes too but this is the most direct. It's also a worst case scenario as the remainder of the hills are all probably < 7%.

Thanks, Google Earth has it as a 260 foot rise at .6 miles which calculates to a 8.2% overall. Still some long climb. I have one 10% here the is only 425 long and a 50 foot rise. I would cringe at doing that like 5x longer.
 
Hi Colorado springs from Lakewood/Golden! Glad you survived the fire!

anyhow, I noticed one thing you missed. Most battery chargers require a 12v power supply. Meanwell makes good ones but youre dropping $75-150 on that. I personally use a 400w power supply from an old computer that I modified for use on my Junsi iCharger 106b+. I got this PSU for free at Staples from a computer they had set for recycling. Not hard to do if you can solder. Youll need to know how to do this anyways to build your wiring harness. You could build 2 of these in an hour, one for home and one for work so you dont have to drag the PSU with you to work every day for cheap. I wouldnt trust a free charger for the life of me. My Junsi icharger makes charging idiot proof (yes i can be an idiot). Hooking up a 5s lipo to a 6s charging cycle can cause a fire. This charger prevents you from making these mistakes and comes with a temp sensor and a PC application for monitoring your cells with cool graphs and charts etc (if you dont mind reading a little German)

Heres a link to a great way to change a computer PSU to a RC charger.

https://sites.google.com/site/tjinguytech/my-projects/convert-pc-ps

Other hidden costs most people dont expect:

New chain and front chain rings. expect ~$50. You cant use a new cassette with old chain and sprockets. Chain and sprocket wear will cause an incorrect matchup and make tons of noise and more wear. Im splurging and changing my entire front drive to a 48t single speed and ditching the shifting mechanism. Who needs all those gears when you have power at your disposal? $90
Zip ties for all those wires ~$5
Wires and shrink wrap, soldering iron etc. if you plan on DIY harness ~$75 $20 for methods harness. (I highly recommend this guy!) http://www.methtek.com
Fenders ~$60, at those high of speeds, any moisture on the road is gonna fly right into your face and make your back wet as heck.
Battery case/bag. $65 bux shipped. Falcon EV makes a great bag for diamond frames.
WHEEL TRUING! most kit wheels that come to your door have been laced, but every single spoke is loose and must be tightened and trued. The junk spokes that came with my wheel started breaking after a few months. Consider having the wheel rebuilt with quality spokes if they arent listed as being built that way. ~$25-$100
Goo filled thorn resistant tube(s) with tire liners. $20 per wheel. You really, REALLY dont want a flat on your motor wheel (takes me 30 minutes to replace a tube, minimum. 3 minutes on the front wheel)


You might consider Lipo as a battery option as well. I love my lipos as if you purchase a battery pack you really cant change it up if you want. As it is right now, Im running three 6 cell lipos in series for a total of 18s (66.6v nominal 74v hot off the charger) which gives me a nice 12 mile range over hills and such. Bumping that up to 10 Ah soon for @ 25 mile range. lets consider the cost:

36v@20AH lipos (cheaper model of battery) from hobby king US warehouse (about 5 days for shipping give or take) = 8x 5s (37v nominal) for 2s4p = $331 not including shipping. 6s batteries are about the same price and youde get more voltage, 44.4 nominal. Thats a lot of battery for not much. depending on your riding style, motor type etc. you could stretch out 50 miles with this set up. 8 batteries will fit well in the Falcon bag with not too much concern for pedaling impediment. Youll rub the bag, but not much. Also with lipo bricks you could change your set up and pump out more voltage but less Ah for those weekend fun rides. With the right controller you could have 24s2p for a whopping 88.8v nominal (100v hot!)and get yourself 35-45 mph for 12-20 miles! make sure the motor/controller you get can handle these massive watt/amp outputs.

CA v2 is just fine. although v3 would be nice, i dont think the cost is worth all of what I use the dang thing for.

I wouldnt use a thumb throttle. I ride off road too much and that just seems like a disaster waiting to happen. Currently using a half twist but thats gonna give me carpal tunnel. moving to a full twist and cruise control.

Once again I highly recommend Patrick @ Methtek. He provides fantastic service, support and has a great buttload of parts that you need at a great price.

stuffs021.jpg


after original build. no batteries yet.

evfalcon2013002.jpg


yesterday, rear rack just asked to be used as a cheap fender.

Ill be checking back up on your progress! GLHF!
 
Check out my build thread, I think its pretty much what you are after.

I ended up going for 15ah for my 20 mile commute, pretty much allowing full throttle the majority of the way (15ah will be fine for 30 miles with pedalling). IMO 20ah isnt going to be enough for your needs.

http://endless-sphere.com/forums/viewtopic.php?f=3&t=42162

Im 6ft 4" 16.5 stone and this pulls me up any hill @ 15mph. Top speed at around 28mph. In my opinion, it is the best commute bike I could possibly build and that is after riding it for nearly 2000miles now.
 
Kinni420 said:
Hi Colorado springs from Lakewood/Golden! Glad you survived the fire!
Fire! Eeek - nothing like being evacuated from your house w/ the National Guard keeping from getting back in.

I noticed one thing you missed. Most battery chargers require a 12v power supply.
Got the power supply covered. These Cosel units are almost indestructible.

Im splurging and changing my entire front drive to a 48t single speed and ditching the shifting mechanism. Who needs all those gears when you have power at your disposal? $90
Really?? Hmm....that's an interesting idea. Guess I still think that the bike will break down and I'll have to pedal 14 miles home, uphill, in the rain, on a heavy bike.

You might consider Lipo as a battery option as well. I love my lipos as if you purchase a battery pack you really cant change it up if you want. As it is right now, Im running three 6 cell lipos in series for a total of 18s (66.6v nominal 74v hot off the charger) which gives me a nice 12 mile range over hills and such. Bumping that up to 10 Ah soon for @ 25 mile range. lets consider the cost:
Still considering that for the moment. I'll be in the 'LiPo for dummies' section. :)

Your bike is very much what I had imagined for my own conversion. Thanks for chiming in. This has been most helpful.
 
sacko said:
Check out my build thread, I think its pretty much what you are after.

Im 6ft 4" 16.5 stone and this pulls me up any hill @ 15mph. Top speed at around 28mph. In my opinion, it is the best commute bike I could possibly build and that is after riding it for nearly 2000miles now.
Nice real world example. Now I need to convert stones to pounds........
I like the bag rack.
 
batteries...
hobby king lipo is good to fit how you want. but can be a hazard if you have it set in series but need to charge in parallel. unless you make a plug that doesnt let you do both. like a d25 printer plug going to all the cells balance leads and next to it your serial plug (made of anderson conectors or simalar) then a small plate on the d25 printer plug that prevent it from being pluged in while the series plug is in.

i small elaberation... say you have 6s (series) lipo bricks 5cm x 5cm x 15cm 5ah each use 3 to make 75v and parrallel that as many times as requred to get 10 or 15 ah.
now, you have 3 negative main leads and 3 positive main leads. this makes up one 6 pin anderson. then the other 6pin anderson that goes into it has 1 positive that comes out and 1 negative that comes out... the other negative and positives get seriesd together with small links.
with the d25 printer cable next to it (hose clamp and or glue etc, mount on flange) the battery side has all the balance leads conected to 21 pins, (7x3) then on the charger plug they are paralleled into one group of 7. alott of wireing but if your up for it i would say its worth it... then you can have balanced charging and a 15ah 75v battery for about $400
you dont need to have all the crazy wire i sugested if you want to use hobby king batteries but if you do you cant short circuit it. alternatively you could just charge 1 paralel pack at a time and do 3 lots of charging each time.
these guys did it...
http://endless-sphere.com/forums/viewtopic.php?f=2&t=35377&p=520286&hilit=+printer+plug#p520286
i still have to set mine up. poped a couple balance cable pins because i forgot to unplug series plug.
anyway, good luck to you.. and looks prett tidy so far :)

http://www.hobbyking.com/hobbycity/store/uh_viewItem.asp?idProduct=9176&Product_Name=Turnigy_5000mAh_6S_20C_Lipo_Pack
T5000-6-20.jpg


also consider a FAT tyre for the rear cos you got not rear suspension....
5847.jpg

http://www.chainreactioncycles.com/Models.aspx?ModelID=5847
 
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