gattm99

Hey guys,

I recently acquired this bike for my wife. It fits her well enough, and she's been riding it a bit on the trainer. She wants to ride roads with me but has a knee issue that gives her lots of trouble on hills. I want a motorpacing companion. We just talked about getting a scooter but she would prefer some fitness and exercise from pedal assist.

This bike is 700c. My wife is over 200 pounds. She wants to be able to spin out 50 watts and keep up with me while I put out about 175 watts or 250 on hills for 20-30 miles. I'm a capable mechanic and would like to do an ebike conversion.

So much dodgy looking stuff out there, and it's hard to decide what to get. 700c complicates the wheel mounted and it seems like the mid mounts are better.

Any advice.

slomoshun

Checkout the Bafang mids distributed by eRad.
https://tinyurl.com/y6wfa4me

Doc_Wui

What's your average speed?

check out the same thing from lunacycle.com if you want a mid drive. I own one.
$400 Bafang motor. Add your battery.

Here's a Dillenger front hub motor. Tradeoff is you want a steel fork for it, not alloy.
Dillenger 700cc for $629. Comes with 36V battery,

There's lots of 1000W direct drive kits on ebay for $200, but the problem with them is too heavy, too much power, and not well set up for pedal assist. I think she would have a hard time going slow (under 20 mph) without the electricity taking over the bike, Also, they're ugly, and hard to pedal unpowered. Good for going to work at 28-30 mph until you crash.

I think the best kit is a rear geared hub motor, about 350-500W, with pedal assist and throttle. LCD display. Ability to run on 36V, 48V, 52V. Those are what I have on my bikes. They're cheap and reliable. Will loaf along all day at 14 mph. Over 22 mph on 48V. Pedals like a normal bike. About $200-250 for the kit. Trouble is, no one sells them in the USA anymore. I had to buy them from China.

chas58

rear hub is the simplest, but if you are doing hills, you need a mid drive. Luna cycles is a good place to get kits from (as is em3ev.com).

gattm99

Decided to buy the 400 dollar BBs02 from luna, but didn't get a battery. Not sure on battery yet. I'd like to have at least 20 mile of range with her pedaling.

I generally average around 15-18 depending on hills and thats usually solo. Thanks for the tip on the rear geared hub.

Joe Remi

If you don't want to fuss with mounting a dolphin battery on the frame, I used a BBS02 with two Mini Cube batteries in a rack bag. I got about 15 miles from each: once I'd drained one down, I knew it was time to swap 'em and get on home. Easy to remove for charging, too.

chas58

What is your speed?
I get 25 miles out of a 36v mini cube, while joe gets 15 miles out of the 52v mini cube.
(technical info: the 36v is 3p, 52 is 2p, so there is a 50% bump in amp hours for the same number of cells.

12ah should be good for you for 36v. Generally you don't want to use more than 80% of your capacity on a regular basis.

Doc_Wui

I saw a post on another forum on these batteries from California Ebikes. The poster has some credibility with me, as I know he has done some customer service work for ebike vendors. They offer both name brand and generic cell batteries with warranty.

https://california-ebike.com/product...ory/batteries/

If I needed a battery, I might look at their generic cell models. I have two batteries that I bought in 2015 with generic Chinese cells that have worked well, plus one battery with name brand Samsung cells that was really disappointing.

gattm99

That looks good, now 36v 15Ah or 48v 12.5

My guess is to ride with me around 16-18 mph she'll need the motor to produce around 100 watts and 250-300 on hills.

Doc_Wui

Harrisburg and Shawnee Forest! Must be pretty country down there!

Depends on what BBS02 you bought. Most are 48V. Maybe the vendors program the voltage.

chas58

Well, 48v is 30% more powerful, 30% heavier, 30% more expensive. Your choice.

The BBS02 can run either 36 or 48v (or 52).

If she is keeping up with you (non assisted) any mid drive motor at 36v should do the job.

If you don't mind the price/weight, get 48v (its going to be stronger than any normal rider).
If you want more encouragement to add your own pedal power 36v (or lower current), will encourage that. ;-)

2old

I'm getting at least 20 miles from my 52V, 6 a-h, Luna mini battery with BBS02 mid-drive. Battery is reported to weigh a little over three pounds, but I haven't weighed it yet. The 52V, 10 a-h one my wife has on her BBS02 is still going strong after more than two years and does double duty in a 48V, 1000w rear hub system (33+mph).

gattm99

Yes, very pretty, lots of short steep hills in the Shawnee. Miles and miles of beautiful empty roads. You should come down here and ride in April around Garden of the Gods. I'll give you a tour!

Despite what you may see marketed I don't think the BBS02 has a specific voltage, though the controller maxes out at 48v and I've read where people have massively over volted it.

I'm not sure yet between 36v and 48v. She doesn't want a motorcycle, but still needs enough boost where she can stay up with me. I think the 36v will really be enough.

Doc_Wui

Lunacycle BBS02 does not run at 36V. It shuts off at 42 volts, I just tried it. Maybe it's user programmable., but I don't have the cable or the desire.

gattm99

Got it all done

MikeyMK

A hub is probably better for a beginner, as it's not hindered by the odd poor gear choice. It doesn't sound like your wife is completely clueless though, and so she may enjoy the sportier process of working a crank motor with the gears.

700c are pretty common on UK ebay, especially in 36v/250w small-hub form. Otherwise known as 28in or 29er, the size difference is usually a reflection of the tyre - all three are in fact 622mm rims.

chriskoz

I got a Luna mid. I think I got a 48v, which is a good size, not so much for speed but for distance.