First Build - BBSHD or Rear Hub

[siasam]

Hello,

Ready to pull the trigger on my first build – I have been lurking for a while, and am looking for some last minute recommendations before I click buy.

Bike – older Giant Sedona
Weight – 260 lbs
Commute – 15 miles one way, a few minor hills
Desired Speed – not a big deal
Desired Range – at least 25 miles on a charge with pedal assist

I will be able to charge the battery at work. This will be strictly a commuter build for sunny days, and I’m more concerned for reliability over speed.

Main Question - If I go with the cheaper route, will I "outgrow" the rear hub and wish I had purchased the mid drive anyway?

I have enjoyed reading the various build threads and researching my options on the forum, and now I’m ready to build my own. I would appreciate any input on the following options –


Bafang BBSHD 1000W Mid Drive Kit (52V battery + luna charger)
$1,250ish shipped from lunacycle

vs

Combo rear hub + battery
48V 1000W rear kit, 247
http://www.ebay.com/itm/48V1000W-26-Rear-Wheel-Electric-Bicycle-LCD-Display-Motor-Kit-E-Bike-Conversion-/371289491857

48v Panasonic 11.5ah shark pack + luna charger, 510
http://lunacycle.com/batteries/packs/48v/48v-panasonic-11-5ah-or-13-5ah-shark-pack/

torque arm, 32
http://www.ebay.com/itm/E-Bike-Electric-Bicycle-Universal-Torque-Arm-Front-Or-Rear-Use-Set-Of-Two-2-/141621289723

$800ish shipped


Thanks!

 

[wesnewell]

The DD hub kit will be the most reliable by a long shot, and a lot cheaper. I'd replace those phase ring connectors with 4mm gold bullet connectors and also replace the fuse and battery wiring with larger wiring and better connectors. 20ah of 12s rc lipo can be had for ~$200 on sale and will provide ~40 mile range @ 20 mph. Top speed will be ~28 mph on 12s rc lipo. You'll never damage the motor on 12s and it should last almost forever. I've got 5 years and ~20K miles on mine and I run it on 24s (sensibly).

 

[Alan B]

See my RidgeRunner thread and article on the BBSHD, links in my signature. The CroBorg, also in my sig, is an example of a high powered hubmotor, and the Novara AWD is an example of a regular DD hubmotor which I used for commuting for awhile with a single rear DD motor.

The range with a BBSHD and 52V 20AH pack is 26 miles if I push it, with less weight. I would not predict 52V 13.5AH is going to make your requirements.

The mid drive will wear out chains at least every 500-1000 miles, and if you don't stay on top of it, also sprockets and cassettes.

The DD motor will hum along, wearing only the bearings. If you have regen and use it the brakes will last almost forever.

If you have really steep stuff the mid drive will climb it without getting hot, whereas the hubmotor will get very hot unless it is a very large high powered hubmotor.

The mid drive will be lighter than a large hubmotor.

If you want to go really slow, such as on a rough dirt road or trail, the mid drive will do it whereas the hubmotor may not have enough torque, and it will get very hot.

When the motor gets hot the controller may also get hot. Either may fail if they get hot enough.

The BBSHD is a quicker and easier install than a hubmotor kit. You still shift with a mid drive.

With a hubmotor things are simpler. Throttle and go.

Pedal assist works okay on the BBSHD. I haven't tried pedal assist on a hubmotor, but I don't think it works all that easily or well on most of them. Bionyx works pretty well but is a closed system, or you can get a special torque sensing bottom bracket and a CAv3 and make a torque sensing throttle setup for any hubmotor that would be decent. But the usual simple pedaling sensor isn't a very good control setup.

 

[siasam]

Thanks for the input -

While the cost savings for the lipo are attractive, I'd be more comfortable using a prebuilt 18650 pack for ease of charging/removal from the bike. Managing balancing and maintenance on higher power lipos may be suitable for my next build (maybe a dedicated off road mid drive fat bike), but I'd prefer a plug and play application for this first set up.

I think my only concern regarding mid vs hub, was if the mid would be worth the ~$500 premium over the hub.

From your comments and research in the forums, I believe if my goal is just standard commuting without concerns for steep hills, the hub motor should be suitable for my needs.


I'll go ahead and get ordering - I'll start a separate install thread when ready, to hopefully help anyone in a similar circumstance with their build in the future.

Thanks!

 

[USAEBIKECO]

I find front hub motors balance out the weight of the bike better.

Motor in front, battery in the back.

 

[puregsr]

Scooter vs motorcycle. I have the 1000w yescomusa DD motor and a BBS02. I love them both.
Ended up breaking the rim off the DD and replaced it at a local bike shop for total of about 150 for a professional strong wheel build and free afterbuild truing/tensioning. Bought a sine wave controller and it is silky smooth, accelerates like crazy, reaches 32mph faster than my BBS02, which doesn't reach 32mph unless down a hill, but eats battery amp if I'm heavy on the throttle.
It also took some work to find 52T/34T crankset and 11-34T Shimano freewheel with both shifters relocated to the left side.

My BBS02 is my go to if I'm climbing hills and need to conserve power. I had to take it apart to lube it and had to come up with some clever ideas for the chainline (mine came out to be 54mm) and added a mega sprocket 40T in the back. Time to replace the 11T after about 400 miles. It certainly makes a cleaner install.
If you don't have hills, DD is easier to live with and I'm loving the PAS function with the BMS Battery sine wave controller and S-LCD3, It's just so much easier to ride.
My wife refused to try my mid drive when I explained that she can't shift under power but she rides the DD which is straightforward.
Save the mid drive for a dedicated monster build. The BBSHD is a different monster I'm sure. I used to think my BBS02 is fast, but not anymore by today's standard or by DD standards. I giggle when I find myself at >32mph in a few seconds and too scared to go faster.

 

[Lurkin]

Hub,18650 pack. Solved.