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I'm trying to decide on what would be the best option for me for my first electric bike. I need a way to get around, and as I live on a hill where I will have to manage a fairly steep incline coming and going I am wondering what kind of bike I should get.

There is a bike on Craigslist right now with a 36V 12amp battery and 500-750Watt motor, but as it is a Huffy bike I am pretty sure it is a kit build. They are asking 700. -- My other option is the Kickstarter kit by Barak Electric (https://www.kickstarter.com/projects/1354698863/barak-electric-bicycle-conversion-kit-electrify-yo) that has a 500 watt motor and 36V 10amph battery, and as I already have a mountain bike laying around I could install it myself and it would cost 655. I have no idea what they would be charging in a couple years when the Lithium batteries die for replacements, but I'm sure I could figure that out then. I don't have a ton of money, so going to a bike shop isn't really an option even though I would love the security of being able to return it if it doesn't work. I was looking into the Currie Electric bikes as they seem quite reasonable, but it doesn't look as though they will have enough power to get me anywhere with their small wattage and SLA batteries (not to mention to upgrade to Lithium with Currie is basically the price of the bike!)

Any advice would be greatly appreciated!

  • A comment as this doesn't directly answer the question. Having looked after both, go for the lithium batteries if you can possibly afford it, they have better discharge characteristics and the weight saving is enough to affect your range and handling. If you're prepared to pedal, a 250W motor makes a big difference, so long as you have sensible gears you can ride up hill and it will feel more like riding on the flat. So worry more about the Wh rating. But with pedalling 24 miles uses less than half of a 36V 10Ah lithium's capacity round here. – Chris H Sep 1 '14 at 8:21
  • The electric bikes I've seen all appear to be based on standard frames, even when sold with a name brand on them, so they're essentially kits anyway. The two special bits are the front fork (sometimes) and, of course, the front hub (you don't want a chain drive or some such). The kit you're looking at provides the front wheel (presumably pre-assembled), so the big issue is whether the wheel fits your bike (including the rim width for brakes & frame clearance). Of course, there's no good way to judge the quality of that kit or how it lives up to its claims. – Daniel R Hicks Sep 2 '14 at 11:33
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First, check your local laws. As others have mentionend, in some countries (EU), maximum power for an electric bike is 250W. Go beyond that and the vehicle will be considered a moped and will need license, insurance and and license plates. Your local laws might also require an assist-only option for your bike to be considered an e-bike. That means usually a pedal sensor, and those can be difficult to install especially with exotic or outdated bottom brackets.

Selecting a kit is not necessarily easy. If you're going to front mounted motor, check that brake type is compatible (disc or v-brake) with the kit and that fork spacing is suitable. E-bike kit should come with brake levers with a cut-off switch so the motor stops pushing immediately when braking (problem with some e-bikes).

Kits can be had cheap, but installing them takes time, effort and experience with bike mechanics. If you got all three, go for it. If you need to get up and running quickly, an entry-level e-bike is probably better option.

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I have tried two ebikes before and to be perfectly honest - they are very poor uphill - almost any hill. The motors are too weak in my view and here the laws won't allow you to ride a bicycle with a motor that has more than 200 watts of power without a motorbikes license (Australia - except QLD). The best motorised bikes I think are the petrol ones such as the common Moped. Much more power and you hardly have to provide a down pedal to push it along.

  • You're not comparing like with like here, and your 200W limitation is localised to the wrong location for the OP. Even so it's quite a bit of help if you pedal – Chris H Sep 1 '14 at 8:23
  • +1: The OP should be warned about regulations regarding electric bikes. This answer clearly demonstrates its an issue in some places - clearly useful information to the community. – mattnz Sep 1 '14 at 20:30
  • If there is an electric hub that has more than double 200 watts, then I'll eat my words. – Fandango68 Sep 2 '14 at 6:18
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    @FandangoAus - Stealth Electric Bikes claim 4500 watts. So clearly a high power hub exits. – Rider_X Oct 7 '14 at 20:12
  • Thanks @Rider_X. I didn't know. But unfortunately here in Australia, we're limited to 200watts or it suddenly becomes a motorbike and you have to get a motorcycle license to ride one with a higher wattage/power. – Fandango68 Oct 8 '14 at 4:59
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I am coming at this from the perspective of converting a bike I have, in my case my Bacchetta Giro 20 ATT recumbent bike [link to my blog documenting my build experience] but before I decided to go down this path I did look at off the shelf e-bikes and for me I couldn't find a reasonably specified [in terms of bicycle components] e-bike at a reasonable or comparable price so as I had the existing bike I decided to go the conversion path.

Based on my experience which was more involved because of the recumbent, if I was considering doing this again I would look for a suitable source bike [either second hand or new with a 68 mm bottom bracket and space to take a frame battery] and then consider installing a Bafang BBS02 mid-drive [750 watts] with a 48V battery. Installation is generally pretty straight forward and really quite quick, the kit is not to badly priced and the motor by all reports is a good performer.

With regards to your Craiglist bike, I wouldn't be considering a 36V battery to power a 750 watt motor as being an ideal option. From what I understand 48V is a better option with the more powerful motor.

Endless-Sphere whilst pretty full-on is worth a visit to get some idea about conversion options.

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From personal experience (Xtracycle's EdgeRunner), if you go DIY or pre-selected kit, make sure you budget for companion upgrades:

  • Battery, motor, controller will add significant weight to the bicycle. Factor in cargo as well (you'd be surprised how much MORE you're likely to haul around if the effort is lower).

  • The motor drive/pedal assist will guarantee higher velocities (more like 20+mph vs 10-15mph). Both will contribute to a much harsher environment for your drive train, braking surfaces, and wheels.

My upgrade path in order of conservative importance:

  • A reliable and trust-worthy brake system is essential. Cable-actuated calipers with a correctly sized rotor (for total ride weight) on a quality disc hub is the bare minimum.
  • If within budget, get hydraulic brakes.
  • Front drive-train including shifter, crankset and chainrings, and derailleur: with battery assist, you spend a lot of time in high gear - make sure it can safely handle the torque you will be dishing out.
  • Rear drive-train - shifter, cassette and derailleur: same reasons as above
  • Rear brake system - if not upgraded at the same time, this is where I would place your dollars last.
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    Your text makes a lot of good and considerable points. Unfortunately it does not answer the initial question. In this context you should know that the stackexchange platform is different from the typical discussion boards. To learn more about how good Q&A should look like, you can take the tour and visit our help pages. – Benedikt Bauer Oct 8 '14 at 8:12
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My recommendation is that if you are good with understanding how electrical motors and circuits differ, thats where you should begin. Stepper motors servo motors are what you are after and amperes is your power output. Watts is how long your power lasts until recharge is needed.

  • Welcome to Bicycles SE. We ask that you write to the best of your ability on this site. This means proper capitalization, proper punctuation, and complete sentences. I have made some edits for you. If you feel I have inadvertently changed the nature of your question, feel free to correct me. – jimchristie Oct 24 '14 at 14:14
  • Wrong. Watts measures power output, Watt-hours is "how long your power lasts until recharge is needed". In fact, I think just about every word of this "answer" is wrong. – Nik Mar 23 '15 at 17:11
  • From Wikipedia: "A stepper motor (or step motor) is a brushless DC electric motor that divides a full rotation into a number of equal steps. The motor's position can then be commanded to move and hold at one of these steps [...]". We can conclude that stepper motors are completely inappropriate for electric bicycles. Perhaps they are used by Shimano DI2 shifters. – Nik Mar 23 '15 at 18:16

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