Narrowed to 2 kits and 2 batteries, help me choose which :)

[blackjackel]

I was looking for a rear hub kit for a 29er bicycle. I wanted the kit to be able to go at least 40mph and the battery HAS to be mounted on the frame of the bike (no rack batteries). I looked for the absolute largest capacity battery that was possible to fit on the frame, looks like water bottle mount was the only way to go. I wanted to the cost to be cheap, and the quality to be decent, basically I was looking for the best bang for the buck.

I narrowed down my choices to the following kits and the following batteries:

Kits:
($662) https://em3ev.com/shop/crystalyte-kit/
- I can't figure out the wheel size... I'm looking for a 29er wheel and I can't figure out how to select that option.
- It doesn't look like this kit offers regenerative breaking like the other kit does.
- Is this kit really worth double the price of the next kit?

or

($349) http://www.leafbike.com/products/diy-bike-conversion-kit/29-inch-electric-hub-motor-kit/newest-29-inch-48v-1500w-rear-hub-motor-bike-conversion-kit-1065.html

Batteries (both 17.5AH) I narrowed down my battery to the panasonic GA from Lunacycle cause they're down the street and their batteries are guaranteed:

[strike](samsung 35G cells) https://california-ebike.com/shop/48-v-downtube-battery-pack-high-capacity-premium-cells/[/strike]

or

(Pansonic GA cells) https://lunacycle.com/48v-pansonic-ga-17-5ah-black-killer-whale-ebike-pack-huge-range/

 

[Chalo]

29 inch wheels are a poor match for a hub motor. The larger the wheel diameter, the less thrust and efficiency you get from any given hub motor. There isn't a single hub motor that works as well in 29" as it does in 26".

Smaller wheels than 26" make the motor work even better, but with inferior ride quality and higher rolling resistance. 26", however, is well established as a default wheel diameter for adult bicycles as well as most other road vehicles.

 

[blackjackel]

so what type of drive system would you recommend for a 29inch wheel?

I bought a 29er 1000w hub motor before and it worked fine for me

 

[d8veh]

That battery is good for 30 amps continuous. 40 mph would take more than that. You need the 30Q cells, which in theory give less capacity, but in practice would be similar to the GA cells at such high currents. In other words you won't get 17.5 Ah from that Luna battery when you run it at the required 35 or 40 amps.

 

[dogman dan]

700c rim is 29 er.

Nothing wrong with a hub motor in 29", if its so powerful you can cruise at 40 mph. It will have less torque than a 20" rim of course, but 3000+ watts will provide enough torque,,, for damn sure.

Also for damn sure, it will take 3000w (peak at least) to have a 40 mph bike. at 48v, that's 60 amps sucked from that poor, soon to die, battery.

The simple recipe for a 40 mph bike is just about any direct drive motor, and 72v 40 amps. With 48v and 30 amps, you can hit 30 easy, and a bit more on any down hills.

I'd suggest you try 30 mph on a bike, on skinny bike tires, before shooting for 40. But if you must, just get yer motor, a 72v 40 amps controller, and some RC lipo packs for battery. 72v 10 ah of lipo is 8 of the 5s 5000 mha packs. 20s You'll have about 10-12 miles of 40 mph there. Almost as good, 6 of the 6s packs. 18s. With my big motor on my cruiser, I hit 35 easy with a 25 amps limit. (1800 watts or so).

Above 30 mph, its better to start increasing voltage, so your battery does not have to get hit with so many amps.

 

[wesnewell]

Hard to give advice without knowing what country you're in. 40 mph is easy and cheap even with a 1000W motor. unless you want to sustain that speed for more then a few miles. If you want to cruise at 40 mph, then you need a bigger motor. See Need Advice in sig. Nothing wrong with 29er bike with a strong enough motor. Both my current bikes will do well over 40 mph and both cost under $700 complete, including the bikes. Both are 26", but with 3" tires on one, the wheel diameter is about the same as a 29er bike with 1.95" tires. I run 24s rc lipo on both of them.

 

[DRMousseau]

29 inch wheels are a poor match for a hub motor. The larger the wheel diameter, the less thrust and efficiency you get from any given hub motor. There isn't a single hub motor that works as well in 29" as it does in 26".

Smaller wheels than 26" make the motor work even better, but with inferior ride quality and higher rolling resistance. 26", however, is well established as a default wheel diameter for adult bicycles as well as most other road vehicles.

My experience with that Leaf 1500 in a 29er will agree with this. Don't get me wrong! It's a big bike,... makes ya feel like a kid again, and a NICE comfortable ride, it'll set me back in my seat, AND hit 40, with my frame-mounted 52V of Panasonic PF's at 40A,... and regen braking is IMO, a MUST for that 29" or you'll be eating brakes like breakfast snacks. It is certainly all I expected and more. Well,.... my 11.5ah battery will only get me about 10-12mi runnin' like that. But I can only imagine how much better it would perform in a 26". And that's why I'm getting anxious on my new custom build. Not wanting to give up that ride comfort, I'm opting for an unusually robust rear assembly that may have a bit of rolling resistance, but with an outer tire diameter of about 25", and a more typical 26' on the front. This is only because I'm designing for an occasional ADULT passenger. With this in mind, a 24" would probably be far better with such a hub motor in my design,... but my passenger needs are only occasional and of short duration, and I need to maintain ADULT design proportions. I still expect near 40, and pretty much same performance (my new build IS heavier) or better than in a 29".

BTW,... 40mph is pretty damn fast on a "bike"! Better have DAMN good brakes, AWESOME tires and PERFECT wheels!!! Especially on the front!!! Without extremes in battery and such, reaching beyond 40 gets tough,.... well, unless Hurricane Ivan is pushin' your light unpowered mountain bike on long paved down hill bridge over open waters. Then you wont see many cars passin' ya at near 50 in a storm!

Consider that 26" more closely, with good tires of comfort AND safety. The edge in performance will be appreciated.

 

[rumme]

40 mph on a bicycle that has 700c/ 29 inch THIN tires ?

You have a death wish ?

You may find out that 30 mph is PLENTY top speed on such a bicycle. If you feel the need to go faster, consider a different bike with smaller tires ?

On these ebikes, most people do not understand the " diminishing returns" involving wind resistance once you start to go faster then around 18 mph . I have a electric fatbike that can do 37 mph, but I often stay at 17 mph...its enjoyable, less wind resistance and you can enjoy the scenery of your ride and ride MUCH more safely. If you fall / crash doing 17 mph..it will hurt , and you can expect scratches/ bruises ....but if you do it at 40 mph...you will almost always suffer much worse injuries that require medical attention.

 

[blackjackel]

That battery is good for 30 amps continuous. 40 mph would take more than that. You need the 30Q cells, which in theory give less capacity, but in practice would be similar to the GA cells at such high currents. In other words you won't get 17.5 Ah from that Luna battery when you run it at the required 35 or 40 amps.

So how many MPH would 30 amps continuous get me?

 

[blackjackel]

40 mph on a bicycle that has 700c/ 29 inch THIN tires ?

You have a death wish ?

You may find out that 30 mph is PLENTY top speed on such a bicycle. If you feel the need to go faster, consider a different bike with smaller tires ?

On these ebikes, most people do not understand the " diminishing returns" involving wind resistance once you start to go faster then around 18 mph . I have a electric fatbike that can do 37 mph, but I often stay at 17 mph...its enjoyable, less wind resistance and you can enjoy the scenery of your ride and ride MUCH more safely. If you fall / crash doing 17 mph..it will hurt , and you can expect scratches/ bruises ....but if you do it at 40 mph...you will almost always suffer much worse injuries that require medical attention.

I won't be going 40 regularly, most of the time i'll be doing 30ish possibly 25.

 

[blackjackel]

700c rim is 29 er.

Nothing wrong with a hub motor in 29", if its so powerful you can cruise at 40 mph. It will have less torque than a 20" rim of course, but 3000+ watts will provide enough torque,,, for damn sure.

Also for damn sure, it will take 3000w (peak at least) to have a 40 mph bike. at 48v, that's 60 amps sucked from that poor, soon to die, battery.

The simple recipe for a 40 mph bike is just about any direct drive motor, and 72v 40 amps. With 48v and 30 amps, you can hit 30 easy, and a bit more on any down hills.

I'd suggest you try 30 mph on a bike, on skinny bike tires, before shooting for 40. But if you must, just get yer motor, a 72v 40 amps controller, and some RC lipo packs for battery. 72v 10 ah of lipo is 8 of the 5s 5000 mha packs. 20s You'll have about 10-12 miles of 40 mph there. Almost as good, 6 of the 6s packs. 18s. With my big motor on my cruiser, I hit 35 easy with a 25 amps limit. (1800 watts or so).

Above 30 mph, its better to start increasing voltage, so your battery does not have to get hit with so many amps.

The motor i was looking at with the leaf bikes is 1500 watts, and the battery outputs 30A continuous, so its more like 1450 watts. I won't need to do 40 all the time, matter of fact I'm probably going to scrap my 40mph idea, i'm going to opt for 30mph.

Would this kit be enough to do 30mph? http://www.leafbike.com/products/diy-bike-conversion-kit/29-inch-electric-hub-motor-kit/newest-29-inch-48v-1500w-rear-hub-motor-bike-conversion-kit-1065.html

With the battery listed in my sig too?

 

[DRMousseau]

Sounds about right. And you can probably expect that 30mph, or nearly so.

Spent the last 20min on "the strip", out in front of my house, to bring some "real numbers" to compare. "The strip" is a measured 500feet of brand new flat and level asphalt. This very motor is on a 29er here. I do have a 52V 11.5ah of Panasonic PFs,... battery rests at about 54V (been enjoying about 7mi of some fun around town today, battery is jus a bit down.),... so this is only something to sorta compare a bit with.

Stock controller in the kit has had max settings (40a) except a speed limit of 30mph. Results from the strip runs??? At these settings, I'll hit 30 jus under a 1/4mi @about 12sec or so. Limited to 30, I'll finish the 500' in about 14sec. Max motor watts read jus over 1920w or so from dead start. These numbers may not add up exactly, but tryin to pay attention to readouts, timer and measured marks, not to mention the other variables here,.... they're close enough to compare with. A couple 2-3 runs were pretty consistent.

I did nothing more than adjust controller to 30A, and ran a couple more times. Max motor watts was jus over 1520w or so,... saw 1555w flash by once. Hit that 30mph at the 500' mark once, and jus past 500' on the following run,... there was perceptibly less "oompf" than at 40A settings, but it did hit 30mph with my nearly half-depleted 52V battery. The last run hit 29.6mph and jus wouldn't quite hit 30.

I'm guessin' in reality, your gonna see 27mph with your 48V@30A, more than you'll ever see 30mph,... and your pushin' your battery limits to see that regularly. I REALLY like the performance of that 52V of PFs,.... although I'd also be happy with 48V of GAs. In a max settings match on "the strip",... I'd edge ya out at the start, increasing distance between us. But nothing embarrassing at all! Beyond the strip,... you'd be getting WAY behind, as I increasing reached closer to that 40mph mark, while your still tucked getting that 30. But that's mostly the difference between 48V and 52V.

 

[wesnewell]

Would this kit be enough to do 30mph? http://www.leafbike.com/products/diy-bike-conversion-kit/29-inch-electric-hub-motor-kit/newest-29-inch-48v-1500w-rear-hub-motor-bike-conversion-kit-1065.html

With the battery listed in my sig too?

It should do 32mph at 27A

 

[d8veh]

30A at 48v would give a speed of around 30 mph, but it depends on weight, hills, tyres, how big the rider is, what the bike is. On a converted road bike, you could get 30 mph with about 15 to 20 amps.

 

[blackjackel]

Ok so apparently hub motors are the oldschool and mid drive kits are where it's at now... Plus someone else recommended i go mid drive if I'm on a 29er...

This is apparently the most powerful mid drive kit on the market: https://lunacycle.com/bafang-bbshd-1000w-middrive-kit/

• Do you guys think that mid drive kit would hit 30mph vs the kit i originally talked about here: http://www.leafbike.com/products/diy-bike-conversion-kit/29-inch-electric-hub-motor-kit/newest-29-inch-48v-1500w-rear-hub-motor-bike-conversion-kit-1065.html
  
  Also, the hub would be able to (if i upgrade my battery later) do 40MPH possibly... would this mid drive kit be able to do the same?
  

Because the mid drive is 1000w instead of 1500w for the hub kit, which one would you guys go with?

 

[Chalo]

Ok so apparently hub motors are the oldschool and mid drive kits are where it's at now...

That's not exactly true. What is true, is that hub motors had already reached their current level of development several years ago, whereas mid-drives are still in the process of maturing technically. There are advantages and tradeoffs to both.

If you want to make the most of a modest amount of power, or if you want to use large diameter wheels, then mid drives are a good choice. If you want to use lots of power or go fast frequently, direct drive hub motors are good for that-- but they work better with smaller diameter wheels.

Geared hub motors are more flexible with regard to wheel size than direct drive hub motors, but they have more noise, maintenance, and points of failure than direct drive... and less maintenance than mid drives.

If you really want to use 29" and not 26" or 24" wheels for your e-bike, then using a mid drive will allow you to extract the best performance from your motor system. But it requires more technique to use it right, and a lot more upkeep than a hub motor. Know this before you buy.

 

[Rassy]

This is apparently the most powerful mid drive kit on the market: https://lunacycle.com/bafang-bbshd-1000w-middrive-kit/

Do you guys think that mid drive kit would hit 30mph vs the kit i originally talked about here: http://www.leafbike.com/products/diy-bi ... -1065.html

I have no doubt that kit will easily hit 30 MPH. I didn't go back to see your weight or bike/battery choice, but I weigh 200 # and have a BBS02 48V 500W (limited to 18A) on a tadpole trike with a 26" rear wheel. Although I currently have the top speed set to 20 MPH, which it does easily, during earlier tests it would do 25 MPH on the flat.

I am biased in favor of the mid=drives over hub motors, particularly if you have any hills. Like many here, I used to just leave my recumbent bike with a front hub motor in high gear most of the time, but with the Bafang mid-drive I treat it more like a regular bike and use the lower gears appropriately.

EDIT: Concerning maintenance, I originally installed this particular BBS02 on a sister's bike over 3 years ago. It was one of the original 500W BBS02s from BMS battery and after a year, with lots of 15 to 20% grades the controller gave out. I replaced the entire system with the newer model from EM3EV just to get her back on the road, and then figured out what was wrong and replaced the controller with a new model controller from EM3EV and it's been on my tadpole now for over two years with no further issues. I'm retired and only use my trike for recreation and exercise, but today was typical with a 14 mile ride.

 

[DRMousseau]

Old school??? eh, maybe.

I mostly ride the pavement,.... 30-40mph occasionally, and at some distance once in a while, occasional hill. Can't beat the hub for simplistic dependability in this purpose. No mechanics, no wear, no maintenance of great concern, and VERY durable for the use of such sort, regardless of power. Also in a rigid frame for the same reasons,... durable, simple, no wear or adjustments, and serves the "pavement" purpose well. Can I run the trails? Sure! Gently, lightly, and not as enjoyably, nor maybe as dependable, as someone on suspension with a mid-drive!

But can't the mid-drive run pavement? Sure! With that high speed and power, why not!?! But don't expect to go as far as a hub without wear, servicing, and adjustments. And IMO, some pavement use is gonna demand that power over the hub! Big plentiful hilly runs for one!

If I'm a "commuter", I wanna KNOW I'm gonna make it to work, on time, dependably with no problems. If I'm gonna push the limits of my equipment and have fun,.... I gotta expect an occasional push too far, in spite of dependable durability.

Road bikes aren't good trail bikes, and trail bikes aren't good roadbikes. Hybids are compromise all the way around and are/aren't good for anything/everything (?). I wouldn't expect a cargo bike to be fast,... but I'd hope it'd have the power needed to haul a load. Hills, paved or not, are factors too!!

Get the idea here?? What kinda compromise or specialize can YOU accept???