Middrive - how many WATTS for heavy cargo bike?

[e-bakfiets]

Hi all,
I have a heavy cargo bike like bakfiets. Carry kids around town, have some nice hills here. The bike came with 250W Dapu brushless hub motor and 340W 18650 cell Li-ion battery. It works okay on flat and mild hills, but carrying kids/load up steeper hills kills battery and just not enough power.

Want to switch to middrive b/c of torque and ability to be able to gear it down. Looking at 1000W brushed or 1800W brushless motor kit. Is that going to be overkill? Maybe 500W middrive is all I need?
Thanks!

[Gr8fun]

Bbshd. Civilized around town but will tear up the hills if geared appropriately.

[e-bakfiets]

Bbshd is the 1000W middrive right?

[commuter ebikes]

Bbshd is the 1000W middrive right?

Yes. Product link here: https://lunacycle.com/bafang-bbshd-1000w-mid-drive-kit/

It is hard to go wrong with a BBSHD.

[e-bakfiets]

This is my bike https://www.virtuecycles.com/product...ondoliere-plus
Looks like this kit will bolt up but will be directly under the crank. So, you think the 1000W kit like that will do well on hills with kids in the basket? It does have a shimano granny gear so I can gear it down well.

[Gr8fun]

Gearing is possible. Really depends on weight and incline to choose the right gearing for needs. The motor will do what you want if you gear it right.
Get a good watt meter, batt. Gauge like the batt man.
Cogs are available for altering cassette to extreme climber. Rings in small sizes are available and will amplify power. Even use an igh hybrid for an even wider range with an under and overdive in axle
. I can go from a top speed of 6 mph to well over 50. That 6mph would be. Over 350 pounds up the steepest hill.we could find. Motor not even hot. Great granny low.

[mtm408]

As Gr8fun stated, given the potential loads you'll be carrying and knowing you've got hills, the BBSHD is a good choice. However, after looking at photos of your bike, you'll want to make sure the BBSHD will fit. Some photos of the bike show an extra bar underneath the main lower tube. This might interfere with the installation of the motor. Take a good look before ordering.

[ykick]

Good point, I looked and still can't quite tell if BBSXX unit will fit? Maybe OP buy just the kit and then if it doesn't work they're only on the hook for return shipping and maybe restocking fee? Easier to return motor than battery pack...

Another option might be Cyclone but not for inexperienced installer?

[commuter ebikes]

I ride heavy (95 lb.) cargo bikes and I use about 2.2kW for cruising at about 35 mph. Anything over 2880W was unnecessary. I weigh 225 lbs.

[e-bakfiets]

All great input. I'll see if I can get the mounting dimensions and see if it will bolt up. Thanks again!

[DantheMan57]

Hello EB Forum:

Like ebakfiets, I am carrying a lot of weight and wear out my cargo bike charge quickly. Not sure if I should just have an extra battery pack or upgrade the motor from the front hub which it is now to a mid drive system.

My goal is to go 20 miles with a kid onboard and 50 lbs of gear.

Here are pictures of the current bike, a Yuba Mundo with an aging battery pack.

https://photos.app.goo.gl/m8jOb4HCoxK1HHVd2

thanks

DantheMan57

[mtm408]

Yuba Mundo's are great bikes and work well with mid-drives. I'd go with the BBSHD. As for a battery, 52v and 13.5ah should easily get you 20 miles, but it's always good to buy as big a battery as you can afford.

[e-bakfiets]

I found a video on Youtube cargo bike similar to mine with the mid-drive motor like bafang https://youtu.be/a06AIxcfap0
So, it might fit. We'll have to check. Also he says in Canada legal power is 500W. What??! We don't have those laws here in the States right?!

[JPLabs]

This is always a tough question for me. I'm not an expert on the topic, for sure, but I'll try to help with it.

Yes, we have such laws in the US. What exactly they mean to us, as builders and riders of ebikes, is a confusing issue. Consider where you ride, and if you need to achieve and/or demonstrate any compliance, or not.

In the states it's vague and inconsistent, but generally 750W is the legal power limit to be an ebike, as I understand. I think one member posted that it's 1000W in his state, someplace out east, but I don't recall where.

The intent of the laws seems to be to make sure there aren't electric motorcycles masquerading as bicycles, which makes complete sense. So, whatever you build, ride it like a bicycle if you want to be allowed to ride where bicycles ride. That's the best advice I can give. Don't flaunt power, don't scare folks by flying past, be safe and courteous, give right of way to those without electric assist, and perhaps the theoretical power level available to you will not become a practical issue. But, get complaints or the attention of a ranger, etc, and you'd better have your ducks in a row.

[e-bakfiets]

I dough up some dimensions. Looks like I need at least this clearance between the bottom bracket and the motor. It will most likely have to be straight down under the bottom bracket rather than forward like on all other bikes.

[calfee20]

Your bike looks similar to another build that is on the forum. maybe you could get some info there. http://electricbike.com/forum/forum/...ff-gates-bbshd

[chooglincharley]

I'd love to know how this turned out...it appears (from first look) that I have a similar Bakfiets and was looking to convert it to electric.

Just started my research and would love an update!

[calfee20]

I'd love to know how this turned out...it appears (from first look) that I have a similar Bakfiets and was looking to convert it to electric.

Just started my research and would love an update!

https://electricbike.com/forum/forum/kits/cyclone-mid-drives/62641-bakfiets-earns-its-flames