First foray into electric bikes, need advice
 

I haven't properly researched this yet, so please excuse any dumb questions. I'll likely update my post as I come across information on my own.

My wife and I are suddenly in need of additional transportation, and an electric bike fits the bill. My budget is limited but flexible. In the near term, I just need to be able to get to work. Right now the weather is nice, and it looks like I might not need more than maybe 15 miles of range, but it won't be long before things start getting cold. Because if this, I was thinking of doing things in stages: First, the electric system, attached to a beater. While the weather remains nice, I'll be shopping around for a recumbent trike, or possibly a velomobile into which I can transplant.

However, my wife spotted something on the local craigslist for $300, in need of a battery:

E BIKE for sale, fantastic working cond.

Is this worth considering, or should I start from scratch?

Looks like a good deal to me. You might want to price out a replacement battery pack first so it doesn't come as a shock after the fact.

That sounds like a good deal to me. If you build your own, it would be ~$300 for a decent new road bike from bikesdirect.com (they're cheap) plus $350 for an eBay motor kit plus ~$400 for a lithium-ion battery. $1050 total. At least that's what I was considering.

Right, but how much of it can I reuse? I'm thinking this isn't as nice as a $350 road bike, and it would be a shame if I couldn't take it apart, and had to rebuy components.

On the other hand, I suppose I can always flip it for more than I paid.

Let's dig into the details here. If I were building my own:

1. Motobecane Track single-speed bike ($309 from bikesdirect.com)
2. 1000W wheel-motor kit ($379, eBay)
3. Lithium battery+charger ($450, eBay)
Total: $1238

That's a nice bike but it's very simple. No kickstand, no quick-release wheels, etc. That's what I like because it keeps the bike nice and light, but maybe you want more frills. It's also single-speed, which is fantastic unless you have big hills to deal with. The battery is a lot lighter than the Craigslist bike and the top speed isn't limited to 18mph.

If I bought the Craigslist Ebike LE, I would immediately strip off the kickstand and change the front suspension for a rigid fork. (Maybe you would keep the fork if you like a comfy ride.) That would probably drop 7 pounds off its weight. I would also strip off the reflectors and replace the seat... all personal preference. Apparently the battery is only good for 5000 miles. That's not much.

In the end, I suppose it depends on your budget. Is 1k a stretch?

No, it isn't, and that looks like a reasonable build. The ebike would likely come close to that after replacing the battery anyway. I do have hills to deal with, but they're not too extreme. I'd probably opt for a variant with gears though.

It looks like the parts from the ebike alone would be worth $300. How much would it cost to ship from Vermont? What service and parts are available in your area?

My experience with suspension forks is they add 2-3 lbs but that depends on which units are being compared. Reflectors weigh very little and used properly could save a life.

The EV Global company went out of production in 2004. A page in nycewheels.com indicated they have a limited supply of parts and have devised some replacement solutions of their own including battery packs.
Reviews of the time indicate these were well designed machines.

I should update my location; It's actually in town and wouldn't need shipping.

What kind of speed are you wanting to get? The Craigslist bike is great if you want something that looks nice and functions fairly well, but you'll be limited on your top speed with it as-is. Definitely go with some kind of lithium battery for it or any other ebike. Lead acid was a necessary evil back then, no reason to suffer with it today.

I built my ebike to be more of an electric motorcycle with pedals than an electric assisted bike. Top speed of ~32MPH on flat ground (I limited it to ~28MPH), bare minimum 20 miles of real range (not the "20 miles of you pedaling and going 10MPH" range). $300 for the conversion kit, $650 for the high quality 48v 15Ah LiFePO4 battery, $100-200 for misc parts (different tires, connectors), and I believe my wife's hardtail mountain bike was $350. Motor and bike have almost 1000 miles and the battery has over 1600 miles. Biggest issue with both bikes was thorns in the tires, but Slime in the tubes pretty much eliminated the thorn flats.

Looks to me like he wants to do a commute that's 7.5 miles one way.

@20mph = 22min 30sec
@30mph = 15min 0sec

Only he can decide what 7.5 minutes is worth to him, assuming e-Bike cruises at 20 and homebuilt can cruise 30.

The 20mph limit is slightly disappointing, but I could live with it. I've looked into products like Flykly's Smart Wheel, and the Copenhagen Wheel, and the latter actually appeals to me if I could get my hands on it, but I'm leaning toward just assembling something myself.

vskid3 or ME_Andy, might you recommend me a specific conversion kit? Two features I'm interested in are regenerative braking, and throttle-less design (like in the above two products, so it feels more like a normal bike) - are these reasonable expectations to have of a cheap conversion kit? I'm also rather small and light, but live in an area with fair sized hills. My acceleration expectations are low, but getting closer to 30mph on level ground would be nice. I don't mind having to shift and/or work a little bit.

I'm thinking about grabbing a beater bike for now, and beginning construction of a trike, based on one of these two sets of plans:

AtomicZombie - The Warrior Recumbent Tadpole Racing Trike

AtomicZombie - The StreetFox Suspension Tadpole Trike


^ I'm going to call around and see if anyone around here can do aluminum welds, as I have tons of scrap aluminum laying around.

Both of my kits were from YescomUSA, one from their site and one from their ebay page. I used this model. 26in Rear Electric Bicycle Motor Conversion Kit 48v 1000w – yescomusa

Regen is something I wanted as well, but the general consensus is it doesn't help much for ebikes and I could only find it in more expensive kits. The kit I used supports and comes with the parts to make it pedal assist (throttleless) using a sensor attached to the crank. I haven't tried it out, so I don't know how well it works. I believe the throttle will override the assist if you don't feel like pedaling.

Acceleration won't be an issue if you want enough power to do 30MPH. Mine will keep with traffic till about 20MPH on its own and I can leave cars in the dust if I'm pedaling. 1000w plus whatever I add will get a bike up and moving pretty quick.

At 20 mph or more I would recommend a rear suspension. Regen would not be hard to add if one knows some basic electrical theory. Getting half the energy back from hills or stop and go traffic stops seems doable. Any streamlining you do will improve range or speed as well as help keep you from exposure to the elements.

Like steel there are different alloys of aluminum that vary in strength.

I agree with Vskid... Don't worry too much about regen, just get some extra range. Even a 500W motor is plenty. That's more than Lance Armstrong could crank out, and you will be adding your own muscle power to it.

Personally I don't think a front or a rear suspension is necessary.

Here's the kit that MMM recommends:
http://www.amazon.com/gp/product/B00GIXZKP8/ref=as_li_tl?ie=UTF8&camp=1789&creative=390957&cre ativeASIN=B00GIXZKP8&linkCode=as2&tag=lifereeng-20&linkId=74ABSSZGKT2WHZ6O

It looks like there are 7 speeds or "cogs" on that wheel? You need to be a little cautious to make sure the chain is the right thickness. So I would look for a bike that also had 7 cogs and disc brakes on the back wheel. However, some of the questions say it will work even for single-speed bikes.

The chain for a derailleur system will be 3/32" wide and a single speed or internal gear hub system chain is usually 1/8" wide. Does the motor shaft have a torque arm that attaches to the frame? Is there a dynamic braking mode?

Maybe I'm an old softy (62 yr.) but I want a suspension, a fairing, and a lap belt if I go that fast for very far.

Well, the commenters on Amazon seem to agree with you :rolleyes:

I'm seriously thinking about buying one now. I have two months of commuting coming up. Figure 40 trips, saving $5 each... that would pay off a good chunk of the bike very quickly.

That looks pretty good. Is that for you, or for me? :p

What do you think, of these?

MMM's recommendation, Aosom 1000w 48v, $380 - claims it also has a "brake controller"

Aosom 1000w 48v, $315 - includes LCD, is this the same kit + an LCD for less?

YesComUSA 1000w 48v, $310 - includes LCD and disk brake

YesComUSA 500w 36v, $190 - looks like the above kit, but with smaller motor and sans LCD and disk brake

How does this look for a bike to put it on?

https://burlington.craigslist.org/bik/5216927639.html

http://cdn.mos.bikeradar.imdserve.co...ass-700-80.jpg

9 speeds on the rear wheel might be an issue because the chain will need to be thinner. Looks like a helluva deal though

I imagine I can probably replace the chain, and the new wheel has its own gears. I'll go take a look at it.

ME_Andy, do you think the 9 speed cassette from the bike I linked will likely fit on an ebike wheel? Would that be a possible solution?

Edit: I could conceivably go with a front wheel kit instead.

Doing some googling... It looks like you'd be OK without any modifications because a 9-speed chain is close enough to fit a 7-speed cassette.

6-speed, 7-speed, 8-speed, 9-speed, 10-speed, 11-speed?
9 Speed Chain on 8 Speed Cassette

Further reading has me eyeing geared hub motors now - not because they provide more torque at low speeds, but because they're supposed to be more efficient, and thus give a bit more range from the same watt-hours. They also allow (almost) resistance-free freewheeling, and are lighter and have a greater portion of their rotating mass closer to the hub.

The downside seems to be that I will eventually wear and destroy the (replaceable) nylon gears, especially if I am going to be carrying much weight.

I'm looking at these kits:

2014 New 36V 500W Geared Front Wheel EBike Conversion Kits Water Proof Cables | eBay

36V 350W Geared 26" Front Rear Ebikeling Electric Bicycle Conversion Kit EBike | eBay

24V 500W Geared 26" Front Rear Ebikeling Electric Bicycle Conversion Kit EBike | eBay

EDIT: This is the cheapest option, might try it out. I wonder, 36v or 48v though?

http://www.elifebike.com/peng/iview....-5S-Q4CQ.2MJWP

The gears might be replaced with metal units after the originals wear or break. Since motor torque is based on current and the number of wire turns of the motor it may be to your advantage to install a switch to go between a series and parallel arrangement of the batteries. Higher voltages may allow for higher rpm and smaller diameter cables. A great deal depends on the capabilities of the controller. My guess is that 48v would be a good place to start. I have seen systems that range from 6v antique tractors to 72v motorcycles for DC motors.

A great site for builds is ebikes.ca ... it has a speed/torque/range calculator.

I have a top cruising speed of 22 or 23 mph. I got the 500-1000watt geared eZee motor from ebikes.ca and bought my 14ahr battery for $480 locally. An ebike shop owner/builder in town looked at the bike and praised the choice to spend extra for the eZee motor. Amazingly, he admitted that the motors he sells and that you get on ebay are from places in China without reliable quality control, but eZee is a noted brand in Europe and they do better, he says. My motor, prelaced into a new wheel, was $550 with tire, shipped.

I could have built cheaper, but I want the bike to be reliable for heavy use for a long time. Since June 10, 823 miles.

No suspension. Converted a roadbike I already owned. 44lbs total weight

Spend for thorn resistant tires. It sucks to get stuck 11 miles from home.

James

Did you ever go anywhere with this, Ecky?

It's on hold until spring, looks like. My transportation needs are presently taken care of, but it's still on my wish list.

Geared hub motors are more efficient if you are riding in hilly terrain or have constant stop and go. But a direct drive is more efficient at cruising speeds. ebikes.ca has a motor simulator to compare efficiencies.

The weather is getting better, and I have some time to look into this again, plus I scored a spare hybrid battery and want to try using some of the NiMH cells in an eBike project.

Bafang ebike kit-

I notice there's a new revision of the Bafang BPM, but nothing has changed in any of the specs I've read. There are also the QQ motors.

Going to do some reading and thinking.

Hi Ecky, any update on this project? Did you get the hybrid batteries after all? Buy the new Bafang kit?

My sister-in-law "borrowed" the bike I planned to do this on and I haven't seen it in six months. Plus, I've moved and nothing is really within biking distance. Chances are when my lease is up I'll move closer to the city, but for now it's on hold.

Bummer! New year, new possibilities...

Update: Found a nice, cheap bicycle. Decided to go with a steel frame, no suspension.

http://i.imgur.com/fxbYdmK.jpg

http://i.imgur.com/4XnrONg.png

http://i.imgur.com/6ohFw4i.png

It will be interesting to see the power to weight numbers for different builds. Just for comparison in the 1980s I mounted a 34cc chain saw engine powered kit on my Huffy 3 speed with 26x 1-3/8 tires. Cruise speed was 25 mph with a motorcycle windscreen for a Virago.

Cool! Will be fun to see you build progress. Keep updating.

What range are you hoping for or expecting? Can you add to that battery capacity if you want? It looks like you are planning your won battery box. I bought the same triangle bag. Although I liked it, it was less sturdy than I expected. I don't think it will hold batteries for long without substantial reinforcement.

I don't need a whole lot of range, and I don't really know what to expect, given my riding environment. I decided on a geared motor because I plan to do a lot of pedaling too, and I understand they are better for freewheeling and have more torque at low speed. Burlington isn't so much big as very hilly, and I mostly want some aid up the hills. If I didn't need more cells to safely support the motor's power output, a single 4.4Ah battery would probably be more than adequate. I briefly considered a 1200w geared kit for only $40 more, but the battery for it would be pricey, and I really want this to remain more bicycle than motorcycle.

For now I'll most likely grab groceries with the bike and do my local social visits on it, because carrying more than a couple of items is difficult on foot and driving to get them in stop and go traffic on the hills here nets me something like a 45mpg trip, which is abysmal for my car. I just ordered a bike cargo rack and plan to snag a milk crate.

Edit: I really missed cycling. It's been a while.

Sounds beautiful. I have a geared motor too, for the same reason: it goes into "neutral" when you are not using it, whereas a direct drive is always engaged.

It is gonna be fun for you, I am sure.

Friction drive?

I had a chainsaw motor drive kit on a bike when I lived in the Cayman Islands briefly. I needed it to (A) arrive to work not being soaked with sweat (I motored in, pedalled home), and, (B) outrun the pack of wild dogs that sometimes roamed around the rural roads on my route. :D (Also filled my pocket with gravel to pelt them, shotgun style, when they gave chase.) Mine was friction drive, with a clutch lever on the top tube to dis/engage.

Ecky: why does the geared motor coast better? Does it actually have freewheel components?

PS: I was in your neck of the woods a couple of years ago for a regatta on Lake Champlain. Very pretty part of the world.

I'm fairly certain all of the geared motors coming out of China can freewheel, but I'll update once it arrives.

Based on my reading, one downside is that there's no chance of regenerative braking, but given that I already have more battery than I need, I consider it to be the lesser trade-off. The gears are also made of plastic and may need to be replaced eventually, whereas direct drive motors are more robust.

A benefit of the geared hub motor is that it's significantly smaller than a direct drive motor of the same size, so my ebike may actually pass as a normal bicycle at a glance. They're also a bit more efficient, and have more torque at low RPM.

And yeah, really beautiful here. Some other places I wouldn't mind living are Lake Tahoe CA and Lake Placid NY - I think these areas are even nicer, but there's less work and in some aspects, higher costs of living.