Conversion kit - Mid drive Vs Front Hub Drive Vs Back Hub Drive

Discussion in 'DIY, Kits and Custom Builds' started by hemant, Mar 28, 2017.

  1. hemant

    hemant New Member

    Hello Everyone,
    First of all, Thank you ver much EBR for such a great website, content and the youtube channel.

    Problem :
    1. I want to build DIY Ebike, so I want to know what do these three kit do the best, worst, merits and demerits.
    2. As I am from India could anyone suggest from where should I buy these kits, like from US or or some other place?

    Thank you.
    Ann M. likes this.

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  3. Ann M.

    Ann M. Administrator

    Welcome to EBR, @hemant! What bike are you going to put a kit on; that will make a difference on everyone's thoughts. Also, what do you plan to use this ebike for? Exercise, daily commuting, hauling stuff like groceries or much larger items? Also, please list the 3 kits you are looking at; the AliExpress link doesn't work right.

    There are a number of simple to install hub motor systems and if you haven't considered it, maybe a mid drive motor kit would be a good choice. Just need to know a little more info from you :)
  4. hemant

    hemant New Member

    Thank you @Ann M. for your reply.
    1. I have a Btwin rockrider 520 but only 26in wheels the older model.
    2. use this bicycle for commute and cross country rides.
    3. I can not list those kits as I am not sure whether they can be shipped to India. Still, I can provide some details
    a. Bionx p 250 pd
    b. Bafang bbs02b
    c. I don't have any idea about front hub drive.
  5. harryS

    harryS Active Member

    There are no local businesses in India that sell or import ebike kits?

    It seems that as these kits are made-in-china, there's no point in ordering from USA or Australia as the box will have to cross the ocean twice. I've ordered some items from aliexpress and been satisfied.

    With your bike, I would avoid front drive, as you have a suspension. A motor on a suspension fork requires more attention to details. While simplest to install, it is also the easiest to break the bike and cause a crash.

    Leaves you with a mid drive choice, or a rear hub. Rear hubs can be geared or direct drive. It seems to me that the Chinese kits focus on the Bafang BBS02, small geared hub motors, or big direct drive motors.

    What you choose depends on budget and how you use the bike. The mid drive is probably a good compromise if you only have one option. Most expensive, but still lightweight and has best power.
    Ann M. likes this.
  6. Ann M.

    Ann M. Administrator

    One note, BionX does not manufacture the 250 watt hub motor systems any more. HarryS has some good points and I would suggest that should you decide to use a hub motor install torque arms to prevent twisting of the wires leaving the motor and spreading of the dropouts. With suspension forks its a must! And use 2, the best are made by Grin Technologies of Canada and are sold at many places that sell kits.
  7. Jolly

    Jolly Member

    Also, you can contact Paul over He is well known in the DIY community and is base in China. He can probably help you with what you need given the location. He sells both mid drives and hub kits with battery.
  8. hemant

    hemant New Member

    Thank you all for reply
    Sure this community is awesome.:):)
    @Joll thanks for the link it's an awesome site, will contact him soon.
    @Harry thanks for the reply I would most probably go for mid drive and will check on Aliexpress too.
    @harryS it's the Binox 250w model that is available in India.
    @Ann M. I will sure make sure to use that torque arms when I do rear hub Installation.

    Can I use a gear sensor with Bafang mid drive bbs02?
    I will contact the local vendors about these kits and will update you all soon.
  9. harryS

    harryS Active Member

    I don't use a gear sensor on my BBS02. Other people like them. I didn't want to spend the $45 USD for a luxury I don't need.

    If you've ridden derailleurs for any time at all, you should have developed the habit of not shifting gears under power anyway. Gear sensors are good for owners that are new to bicycles or that don't understand shifters.

    My wife has ridden shifter bikes for many years, but never shifts gears, while I enjoy starting in low gear and clicking up as I gain speed, and clicking down again for a stop.
  10. hemant

    hemant New Member

    Hmm that makes sense, I will keep that in mind. So that means that this gear sensor can be attached to bbso2 model no need for special adapters or anything?
  11. harryS

    harryS Active Member

    The US version of the bafang kits have a dedicated connector for a gear sensor. Mine does. Do not know about other versions. I believe the motors have factory programing for faster motor response too. Otherwise, you could just add one in parallel to the brake sensor.

    I should have added that trail riders might benefit from the ability to shift under power. I might change my attitude if I knew I would fall off a mountain if I cut power going uphill, but I wouldn't be doing that anyway.

    Here's more reading om the topic.
  12. steve_rolfeca

    steve_rolfeca New Member

    The Bionx kits have an internal strain gauge that continuously monitors how hard you pedal. It provides the smoothest, most silent and organic-feeling pedelec boost on the market. Once you get going, there is no surge or delay in turning on or off, creating the intoxicating feeling that there is no motor involved- you just inherited superman's legs!

    Range is excellent on the lower assist levels, with matched, proprietary battery packs and safe lithium cobalt technology. The battery and motor unit communicate with each other, and aftermarket packs are not an option, although there is at least one vendor who rebuilds the Bionx packs. This makes for a less expensive option when your pack wears out.

    Bafang-based hub drive kits do not offer nearly as good a pedelec experience. Sensing is crude and laggy, gearing is noisy, and most users rely on throttle control. As good or better than Bionx if you just want effortless no-pedal power, but poor if you want a seamless electric pedal assist that seems to disappear into the background.

    Battery packs are completely up to the user, allowing more scope for customizing range VS power and cost. However, it's also buyer beware, with lots of questionable choices out there.

    Bionx are also as close to zero maintenance as you can get- designed and built in Canada, water sealing is excellent, the hub drive has no internal gears to strip or need replacement, and doesn't stress the drive chain. The warranty is longer than Bafang.

    In contrast, the Bafang-based drives (mid or hub drive) all have internal plastic idler gears that are a weak link, problems with drawing water into the electronics, and a history of controller failures. Maintenance and repair issues are commonly reported on the forums.

    The latest mid-drive Bafang versions seem to be better developed, but they place tremendous stress on the derailleur and chain, twice as much or more than human power alone. Expect to blow chains and other driveline parts regularly if you ride aggressively.

    However, Bionx kits are very expensive- at least twice the price of any Bafang-based product. Tech support is excellent in North America and Europe, but I don't know about India. Best if you want a sealed, no-fuss experience.

    Bafang kits are much more affordable, have a strong DIY community on various forums, and there are more sources for replacement parts when they break. Best if you want to experiment, tinker, and especially if you want to hot-rod your kit for more power.
  13. hemant

    hemant New Member

    Thank you Steve
    After inquiring in multiple stores across India I found that Bionx no longar sells in Inda , there are only few product remaining mainly p 250pd model .

    So my question is What would be preferred
    1. Should I go for this old kit available in India
    2. Buy a new one from recomended by @Jolly
    2. or simply buy a Kit from Aliexpress as I mentioned in my earlier post

    And one more thing if I buy a 500W Bafana bbso2 and 36v and 15.5Ah Battery what is the expected Km range of the battery.

    Thank you
  14. steve_rolfeca

    steve_rolfeca New Member

    I couldn't find any info for the Bionx p 250pd.

    It's important to establish which generation it is- the early p250's used nickel metal hydride batteries, so performance is very poor compared to the more recent versions. I believe the P250 DX is the Lithium version.

    Also, the first-gen Bionx kits used a different communication bus between the hub motor, battery and controller. They are no longer supported, and can't be upgraded.

    I can't comment on em3ev vs AliExpress, as I have no experience with either.
  15. Thomas Jaszewski

    Thomas Jaszewski Active Member

    Aliexpress is a gamble unless you know the vendor. EM3ev is one of the best and longest in business kit seller. I've used them numerous times over 4 years.
    JRA likes this.
  16. harryS

    harryS Active Member

    I've purchased a Bafang SWXH hubmotor and controller kit from on their dedicated website. Elifebike offers a more production selection on aliexpress, although whoever is using this elifebike name there may have "stolen" it. In any case, I've bought an LCD-3 display from their aliexpress site. t arrived, and I ordered a second one last week. Of course, that's a $42 part vs a $350 BBS02 and a $300 battery,

    Here's the Elifebike mid drive page

    Reading on other forums, I also see what Thomas says. When people have a problem with EM3EV, the owner steps in and resolves things.

    Pictures I've seen of recent batteries constructed at EM3EV show very well constructed batteries too.
    Gregory and Thomas Jaszewski like this.
  17. Thomas Jaszewski

    Thomas Jaszewski Active Member

    Good stuff about elifebike as well, once the language barreir is breached. Love those Q motors and good roports.
  18. hemant

    hemant New Member

    Thank you @Thomas Jaszewski and @harryS

    Update :
    I was able to contact Bionx India and the have a few 2nd Generation 250pd model [which was discontinued in 2015 or 2016] available and they are going to provide me a test drive from one of their previous customer.
    So will be trying it out , then I will Decide whether to go for Bionx or Bafang from EM3EV.

    Pros for Boinx:
    It is safe to buy Bionx as they are still in available India
    No additional shipping cost.
    Great integrated technology.
    Kind of weather proof [not 100%].

    Cons for Bionx
    They are costly.
    Older version model.
    Only one model available to choose from.

    Will get a test drive and then post an update.
    Thank you
  19. Thomas Jaszewski

    Thomas Jaszewski Active Member

    Cons also bionx systems ive seen have proprietary battery communication with motor. Expensive battery replacement. But maybe no all their systems, i dont keep up, but had frustrated customers that had problems and no off the shelf options. Paul, EM3ev has fabulous batteries.
  20. rchenail

    rchenail New Member

    I was debating between mid and hub but have thought that I would be better off with mid since at first I would install it on my 26" MTB bike (old Giant Cadex with Rockshox) but then I thought I might eventually put it on my Giant Anyroad Comax (700c). Both are composite bikes. Just wondering if these are suitable for this application.
  21. Thomas Jaszewski

    Thomas Jaszewski Active Member

    Are both bikes the same size bottom bracket? What type of bottom bracket are they? Sorry, a busy day here and I haven't looked them up....I think the newer bike is a press fit BB. The older MTB may be a 68MM- 73MM. Mid drives are fussy kits. If you don't need a hill climber a hub is less maintenance. But a hub will obviously not fit both with differing wheel sizes.

    The press fit needs an adapter,

    If you can use a hub drive and have mild hills I'd look at MAC drives. Nice compact gear drive motors. I have both motors and have had all the Bafang mid drives. I'm converting to hub drives since I just don't need the hill climbing.

    What is it you want to do with the bike? Commute? Trails?