Good Deal? Or Rip Off?

General Discussion about electric bicycles.
jag   10 kW

10 kW
Posts: 777
Joined: Feb 16 2009 12:12pm

Re: Good Deal? Or Rip Off?

Post by jag » Nov 10 2011 1:40am

Edit: Added some cost estimates in text below
pjpeter wrote:I pm'd Steveo and posted a reply here but nothing - oh well, thanks anyway all who did post and try to help me,
You can always try to post with a specific title like "Help with ebike wanted in Toronto, ON area, Canada".
Or you could just ask if some nearby ES members would like to meet up and try out each others rides.

It is not clear to me if the best solution is to fix your bike or buy/build a new bike. If you are willing to take a bit of risk you could try your current bike at 48V. You could either try to borrow a 48 V battery or add a 12V battery in series to your exisiting one by buying or borrowing a small 12V lead acid battery. These are found in wheelchairs, motorcycles and computer UPS. Another alternative is an RC hobby 4s lipo pack. If 48V gives you the speed you want you can buy e.g. a Ping 48V, 10Ah battery, or the more expensive but higher power cell_man battery below if you want to upgrade to a more powerful bike later. Then deal with the maintenance on the bike you have. While most 36V controllers will work also on 48V there is a risk that the controller will blow, but I think the risk is pretty small.

If you go for buy/build new I would get something significantly better. Ypedal has an A2B. He wanted to try it on 48V, but not sure if he did.

Personally I think building is a better deal. For the $2000+ of a quality pre built bike you can get a motor kit and battery for around $1000, then have another $1000 for a really good used bike.

I would go for a full suspension bike with enough triangle space for the batteries. Try out several different bikes in bike stores, or if you have the time kijiji/craigslist, to find one that fits you well and rides nicely. I think many people here pay far too little attention to the bike. With patience a good used full suspension bike, that has been mostly standing in the owners garage can be bought for less than 1/2 new price. I paid $850 for the Jekyll below, and have bought other good Cannondales for as low as around $400.

The currently best option for hub motors is the Ezee/BMC/Mac geared hub. Does your hills more efficiently than a comparable direct drive, and is lighter. ebikes.ca sells the ezee and provides Canadian support and warrantly. Various US vendors on the list sells the BMC, and the MAC can be bought from cell_man in China. All are quality products. Cell_man also builds batteries, and is afaik the only current source of triangle shaped batteries. See the downloadable .pdf file here:
http://endless-sphere.com/forums/viewto ... 30#p415295
The triangular 16s5p battery is $600+ship.
Total e-kit costs could vary from around $1000 (Cell_man mac hub motor+wheelbuild, 4110 controller, triang batt above, ship) to $1400-1500 for a BMC V2S kit from Ilya + above cellman battery or the complete Ezee kit with 48V LiMn batt from ebikes.ca. The Ezee battery and controller are waterproof, but battery does fewer cycles. The A123 cells in the cell_man battery are better both at high loads and low temps than other lithium, and like other LiFePO4 should last 2000+ cycles with is 2 times or more longer than most others.

I built a Cannondale Jekyll with a BMC v2s:
Image
http://endless-sphere.com/forums/viewto ... =4&t=23518
With a 36V battery it does Canada street legal 35km/h With a 48V battery about 50km/h.
The ebikes.ca ezee has a slightly different motor wind. will go slightly slower.

I use between 15 and 20Wh/km in mixed riding around 30-35km/h average speed and 40-50km top speed.

Where the geared Ezee/BMC/Mac hub really shines over other hub motor alternatives is on uphills and other high load conditions (e.g. acceleration). The graphs below compare the efficiency of the BMC (ezee and Mmac will be similar) with that of a good direct drive (9C) and an the highest efficiency RC motor currently widely available (Astro). Values below are for an optimized setup (slick tires, tucked rider etc). Average Wh/km will be higher for most builds but the general relationship between the motors will be the same.
Image
http://endless-sphere.com/forums/viewto ... 15#p289416
Last edited by jag on Nov 10 2011 2:41pm, edited 2 times in total.

pjpeter   10 W

10 W
Posts: 82
Joined: Aug 31 2010 5:39am

Re: Good Deal? Or Rip Off?

Post by pjpeter » Nov 10 2011 1:09pm

Thank you jag, that's a really nice bike, very stealthy and looks very solid and it's great you are able to do so much with it - great job. I was hoping to get a reply from you in particular since you were the one that introduced the idea of upgrading my current bike - it had not occurred to me before you said that. I didn't want to risk getting in trouble with the admins on the board for double posting and was hoping you and the other commentors would reply so that's why I kept with this thread rather than starting a new one.

By the way, I've found I was wrong about my Li-ion battery - the 36V stock one - it's still going strong - it's the temperatures that have been getting it down. During the heatwave the past week (temps 17*C sometimes but consistently 8*C+) I found it was able to make the trip home with some juice to spare. It's not totally scientific, since I have to pedal some of the way and I may be doing a bit more or less, but it definitely held up a lot better than when it was near/sub zero last week when I had to pedal my last hill pretty much all the way virtually unaided. The speed over the trip is noticeably better too - 27kph vs. 24kph when it was colder (so probably voltage dropped from the temps). Still would like to go faster than that though (especially when it gets colder - not the other way around :p).

The idea of upping the voltage to emulate a 48V battery intrigues me, but I'm worried that the controller would blow or other wires melt since it is rated so low in terms of amps and I don't think a larger controller would fit the built in box (the one included looks to be about 1/2 the size of the one on your bike).

I looked into YPedals info a lot, he has been adding booster packs, but he has to wire them direct to the motor rather than going through the battery inputs to the controller. I almost bought a used 2010 A2B a few weeks back for $1900 local, but I need a removable battery and that one included one built in - plus from my reading of it the geometry of those bikes is such that it isn't safe to let go of the steering for even a second even at stock speeds and that faster wouldn't be that safe at all (though now they seem to be coming out with an Excel?). Plus the rear suspension is apparently very bad and everywhere I've read people replaced it.

Costing out the 48V battery, controller, spare charger, real wheel w/motor and case from ebikes.ca (or ebikes.ca and a combination of other recommended sellers) it came out to between $1400-1600 for the electronics plus taxes and shipping. Plus needing to get a good solid bike frame with disc brakes and lined tires and support for a rear rack plus time to put it all together plus my lack of experience and the fact I wouldn't have any sort of warranty all the whole system (and my worries about not being able to waterproof my motor) is what made me consider just getting a Pedego Interceptor instead. I'd heard many good things about it - I don't know how good it is on hills or accelerating, but stock it goes 48kph, comes with all the premium upgrades (Kevlar lined balloon tires, etc...) + the stock welded rear rack and I was able to get my foot in the door with a deposit to get the 2011 pricing ($100 less than what it is now). There have been delays though and I don't know when I might actually get to buy the thing.

Thank you very much for your replies, still not quite sure. I read through your thread by the way - that really is one sweet setup you've got there - I hope it's not impolite of me to ask, but how much did your setup cost?

Thanks,
Peter

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