$700 ebike build plan. Opinions?

So i'm ready to take the plunge into ebikedom, but this is my first time doing anything with an eBike.
FYI, i like to pedal a lot but don't like being discouraged by hills. So i'm looking for a little boost up hills, not a speed demon setup. And the freewheeling geared hub is paramount to making this work.

So here's my setup i've came up with ( estimated shipping costs are included ):

1x cell_man 250w front geared hub motor kit, 14amp controller ( air shipping ) $250
1x icharger ( entry level 6s model ) $95
4x zippy flightmax LiPO 20c 6 cell 5000mAH batteries = $225 ( run in 44v )
1x TURNIGY Watt meter ( this is effectively my poor man's low voltage cutoff. ) $30

1x Power supply = ??. The ones on hobbyking.com seem to have terrible reviews.
I'm thinking one of those electronics hobbyist DC power supplies would work, but am not sure what voltage/amperage is best.

Total: ~$600 ( and some room for a DC power supply )

My main concern is that 44v is an odd voltage. I wonder if this will cause me to smack up against the LVC of the 14a controller. hm.

12s is a great voltage for a controller made for 36v. It should be right about 50v fully charged, and a 36v controller may have 50v capacitors in it. Chances are that is what the 250watt controller is. For a controller built for 48v, you'd want 14s lipo, for the reason you mention. Most of the higher watt kits have a 36v controller that can handle 48v, and have a cutoff set for 36v. 63v caps in them usually.

Got any old lead batteries around? I was using some old sla batteries and a 12v charger for my power supply. Ghetto, and of course can't be carried around, but it saved me a few bux for now. I had the stuff already, and recently added a new 12v deep cycle battery so I'd have charging capability without a plug if I want it.

I would love a review when you get the kit together.

For that kit I agree with Dogman, 12 series Lipo would be better. I like the 2X5 series for an assist on my bike ( a 9C
with John rob holmes 25 amp 36 volt controller=perfect assist bike top speed around 20 MPH) But the cellman kits are a tad slower so may wimp out at a top speed of 15 MPH. But on 12 series you will average around 46 volts and 20 MPH top speed. Since you are spending some money might as well get a boost, I am afraid that that kit on lower voltage will be too week for anyone.

Lastly Please invest in a low voltage alarm for lipo so you dont kill them young, for 13.95 the GT voltage anayer will beep at the cell level LOw voltage cutoff that you select. It will also keep track of your lowest voltage during the ride. I highly recommend that turnigy meter too.

http://hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=8980

I am okay with 15mph. There is a lot of stop & go out here in Portland, so mostly i just need torque to help up occasional hills. I figure i am going 3mph on somr with furious pedaling, so even 10mph up a hill is an improvement.
Ahh... too bad the hobby packs don't come in a 7 cell configuration. And other configurations are just weird. It'll have to do.

Lead acid's not gonna work for me. I get to haul this bike up stairs to get to my apartment. The zippy flightmax batteries are about 1lb each. I don't have any lead acids lyin' around anyway.
I know it's crazy to jump into LiPO

Ian; those seem super cool. I will take your suggestion and buy some of those.

I'd be really curious to see how it all works out too, I think you have a good plan!

Do you know what ratio the geared motor's planetary is going to give you? All I know is that the 5 to 1 of my Amped Bikes geared motor kit is too high geared to effectively climb hills to my satisfaction, but there again it is faster on the flats, so it's a trade-off.

I think many of the geared motors have a 8 to 1 ratio, and you might see if there is a way to calculate this, maybe those values can be plugged into Ebike.ca's simulator and give you an idea. If the gearing isn't ideal, you might be wasting a 44V battery on a kit that was optimally geared for 36V, and won't give you any more speed, just longevity, and you might also consider the Amped Bikes LiCo battery, it's the same Nano - Tech LiPo chemistry, and you get a charger with it. Sure it's "JUST" 36V, but you have to ask yourself, will that 2 lbs that you save with geared motor that isn't going to shed heat as well as a 9 X 7 9C motor, or go as fast on 44V, maybe get a Amped kit with the battery for $50 more ... just a thought, don't let me change your mind.

Here is the link:

Lithium Battery Tube and Motor Combo's ..... Pricing for the Direct Drive Combo is $746 + $50 shipping

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http://www.ampedbikes.com/completel.html

Let us know what you find out!

Cell_man tells me that 44v will get me a max speed of 18mph on this kit. So i understand it may not be for everyone!!

I've already weighed the pros and cons of geared VS non-geared and i absolutely prefer the efficiency, weight, and freewheeling of the geared motor because i like to pedal a lot ( this isn't replacing a car ). I've ridden 3 ebikes with direct drive motors and the amount of drag made pedaling suck! In fact, it prevented me from getting an eBike about 2 years ago until i heard about geared hub motors!

I rode a bionx 250 watt kit and was *very* impressed, so i have a suspicion this will perform similarly, sans regen ( meh ), and proprietary battery that costs in the neighborhood of $1000!!

As for batteries..

I strongly considered the amped bikes stuff far before all of this, i considered the ping packs too... but the RC hobby packs are just a hell of a deal; i can keep adding capacity two packs at a time.. and if part of it goes bad, i'm out $50 rather than ~$500 or so. I am also not intentionally choosing 44v; but those 6s batteries seem to be the best value, so why not .

dogman said:

12s is a great voltage for a controller made for 36v. It should be right about 50v fully charged, and a 36v controller may have 50v capacitors in it. Chances are that is what the 250watt controller is. For a controller built for 48v, you'd want 14s lipo, for the reason you mention. Most of the higher watt kits have a 36v controller that can handle 48v, and have a cutoff set for 36v. 63v caps in them usually.

Got any old lead batteries around? I was using some old sla batteries and a 12v charger for my power supply. Ghetto, and of course can't be carried around, but it saved me a few bux for now. I had the stuff already, and recently added a new 12v deep cycle battery so I'd have charging capability without a plug if I want it.

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OT and just wondering - can one extract useful levels of charge from a moving vehicle's DC socket? I'm having visions of a flight of Keplered road bikes, and a Prius support car handing up the lipo like water bottles. 8)

Most likely the DC socket built into any car would handle one smaller lipo charger, like the 50 watt ones I have now. It's sorta what they were designed for, charging the RC helicopter out in the field. They take about 90 min to charge a 5s 5 ah pack. A bit longer for a balancing charge. So the socket would not be likely to have the capacity to run several 200 watt chargers to get it done faster.

There is of course, enough higher voltage DC power on a prius to charge a huge lipo pack, It just doesn't come with a handy plug to tap into it for obvious safetey reasons. It might work though, to hook a larger wire directly to the 12v battery in a car, using a thicker wire than the cigarette lighter plug. Then you might get away with several chargers, or a larger one.

At some point though, if you have a car or motorcycle along on the trip, It becomes easier to just buy more lipo and have the car carry it for you. Then recharge all of em later. The reason I set myself up with a big deep cycle battery for power supply is that the death race in AZ doesn't have plugs out in the pit area of the track yet. So I figure a small generator and a battery will be the way to go if I want to charge at the races. The same setup would be great for camping too, but with a bad back, I've kinda given up on rough sleeping. But I could take the bike to the mountains on a day trip, and get one recharge out of the battery.

Hi neptronix - I have a similar charger that I power with a power supply from a discarded desktop computer. You can read about it here - http://endless-sphere.com/forums/viewtopic.php?f=14&t=19907. I did a little modification (no opening the box and no soldering 8) ) and it seems to work great - jd

I would suggest this for a power supply for your charger: http://cgi.ebay.com/350W-13-5V-DC-Regulated-Switching-Power-Supply-K004-/170528928281?pt=UK_BOI_Electrical_Test_Measurement_Equipment_ET#ht_5780wt_1372

I am using that type of power supply to bulk charge my pack actually.

I think i'm gonna try to find something locally first for the power charger.

I learned about 5s cells and the 10s charger. This means i can balance charge 2 packs at the same time, which i dig.
This is also cool because it's 37v, and the LVC is set to 30v on the motor controller. So i don't have to worry about that as much.

Bought all the batteries, an icharger, bunch of wires/connector, a cell meter, a watt meter, all for just a hair under $400 shipped. So far i'm ~$650 into the build and all i foresee myself needing is a power supply.

So i'm in half of a bionx kit.. awesome.

Rock on! We should plan a ride sometime! I won't hold your "cheating" against ya! (now I just put my foot into my mouth, you're not using lead acids like my dad is currently, so I won't be able to keep up with you at all! )

Seriously though, if your ever looking for a ride, I've been networking with a lot of guys lately for bike riding in general, and they are all down with E-Bikes, many are very curious to see/try one.

I'd love the challenge to try and keep-up with ya on your E-Bike and me on my MuddyFox. SOOON I will be Keplerized!!

I'm about 220lb so you probably have an advantage

I may head that way, haven't explored much of northern Oregon, and if the eBike is stable, i'll probably take it such long distances

Neptronix -

What part of Oregon are you in? I'm in Eugene.

Power supply: I second the computer power supply advice...you can get them for next to nothing and even the sort of junkier ones these days put out 300-350 watts...which is a lot and will provide all the juice the iCharger will ever need. If you do burn one out, go to goodwill or some old second hand store...or craigslist free section sometimes...and get another one. All you have to do is cut and cap all the wires other than the yellow and black and that makes one heck of a good auto-battery type source. You tie all the yellow together for the + and all the black together for the -.

I'm in Cedar Hills/Portland, quite a bit away. But i LOVE Eugene and want to visit some time soon.

Yeah, i could go the ATX route but let's just say i've been rubbed the wrong way by ATX power supplies more than once as a PC tech O_O

BTW Tostino, i looked those power supplies up and they look like counterfeit meanwells. The price is appealing, but i'm gonna see if i can get a genuine one at a good price. RC guys seem to like those. Thanks for the tip nonetheless!

neptronix said:

I'm about 220lb so you probably have an advantage

I may head that way, haven't explored much of northern Oregon, and if the eBike is stable, i'll probably take it such long distances

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Just let me know where and when, and I'd be happy to come closer to you if you'd like, I'm trying to get around 30-50 miles in a day to prep for my first big ride.

I'm going to get my Trekking bars soon too! The only thing I don't like about my MuddyFox so far is the MTB style straight bars, they kill my hands about 20 miles or so into a ride and then my shoulders start to ache.

I have straight bars and i don't like those either. I have a trek 930 which is pretty much the same as yours, but with some high end components.

Anyway i ordered all the stuff.. waiting.. waiting...

Check these babies out!!



These bars are really an amazing solution to the problem of "how do I use my "straight bar controls on my bull/drop or other non-straight bars?". I met a guy named Jordan on my way home from the Portland Century event that had a set on his bike with full panniers stuffed to the limit as he was moving to his new place.

Jordan is a great resource for me since he does loads of touring and is planning a trip on his bicycle from Portland to Chile in the next month or so.

When I asked him "why Chile?" he said "because it's the furthest southern point of South America, if there was a ferry to Antarctica I would ride there too!"

Gotta love that drive and enthusiasm!

neptronix said:

Yeah, i could go the ATX route but let's just say i've been rubbed the wrong way by ATX power supplies more than once as a PC tech O_O

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Lol ok... "Never rub another man's rhubarb!" I guess! (Bonus points if you know where that quote comes from)

Yeah Eugene has nice paths, and good bike lanes. Portland isn't bad for it either. I will be up in Portland for the NEDRA drag races 2 weeks from now...on the 10th. I may very well bring my project with me if you'd like to meet up and see it.

Hey as a PC tech have you ever hooked ATX supplies in series?