Long tail conversion

[Katysax]

I have a Rans crank forward bike to which I added a long tail Xtracycle trailer several years ago. Mostly the bike is used for errands to the grocery store. In the past I owned a retail business and I used the bike to pick up supplies. My fantasy for years has been to put an electric motor on the bike. I’m thinking about it again. I’m thinking either a front hub or a crank drive. The front hub would be the easiest. There is so much weight on the rear I’m thinking front hub would be more balanced. Because of the conversion to long tail the chain is very long. I’m thinking a mid drive might be too much strain. On the other hand with heavy loads the mid drive might be better.

I don’t plan to tour with the bike. The big size makes it unwieldy in many situations. I just want to use the bike as a short distance 20 mile or less cargo hauler with an electric assist. The tires (Schwalbe Marathon) and mechanical disc brakes should be adequate. I’d appreciate suggestions on motors,etc. probably I would have a local business that does many conversions do it for me. I live in the San Fernando Valley. Mostly the terrain is flat to easy hills. I do live less than 1 mile from mountains that I like to ride but I’ve never tried to haul cargo over the mountain.

I don’t need to go over 20 mph and I can even live with a throttle and controlling the assist input with my hand. I do want the bike to be able to handle a total weight over 300 lbs in rider and cargo.

 

[indianajo]

I just changed the stretch cargo bike left from rear DD hub to front geared hub two weeks ago. I like it much better this way. It saves 20 lb on the back, drags a lot less than DD when I pedal (at least 2/3 the distance) and uses a lot less electricity on the hills. I diverted from riding 55 mph low grade state highway 3 to hilly 30 mph Jack Teeple road when I installed electricity. The DD motor was using from 50 v to 43 v out of a 17 AH battery on my 30 miles trip. The geared hub drive used from 50 v to 48 v on the same route. I gross 330 lb with supplies on my way out to the summer camp. I used a 1000 W 48 v geared hub motor from ebikeling.com I bought in 2017. He no longer sells 48 v geared hub motors, only 36 v. If I bought one now I think I would buy a MAC 12T from lunacycle. Electric-bikes.com had Mac 12T but he cancelled my order for one because he said 330 lb was too heavy for a 48 v geared hub motor. Electric-bikes.com wanted me to order a a DD crystal motor at 2.5 times the price of the one I bought on e-bay.
I didn't like the PAS on the ebikeling bike, that accelerated at 500 W minimum to 11 mph in PAS 1. That is too fast for riding in the 12" pavement available outside the line at the edge of Hwy 3. That is also too much acceleration. Also if I forgot to turn the PAS down to zero when stopped the pedal would whack me in the ankle if I wound the crank backwards to the top to make takeoff secure. I like the throttle control that came with the $189 DD motor kit. If I rode with power continuously, the throttle would cause pain in my hand. But PAS 11 mph minimum is too fast.
If luna runs out of macs (he was out of 2.1" tire geared hubs when I bought from ebikeling) I would think about a leaf direct from china. They have been in the business atleast since 2017, but used to sell on ebay, now they don't. Or maybe the motor wheel from magnumbikes.com although it is only 500 w and limited to 13 AH, which is not far enough for me. In January I burned off from 51 v to 43 v in 22 miles RT to the barber, out of 17 AH. It was only 45 degrees that day.
Conversion wasn't that hard. I made a strip of sheet steel 9" long with holes to wrap around the front fork to hold the torque arm on the motor. I used 2" of aluminum angle to a frame hole, and a top of a SPAM can with holes in it to wrap around the seat post, to suspend the controller under the seat. I built a battery mount out of 3/4" aluminum angle for the front rack. Home depot has some #10 screws and nuts, but if you want stainless screws that don't rust and elastic stop nuts that won't unscrew those come from mcmaster.com in $6 boxes of 50 or 100. I don't buy the angle from mcmaster because the length adds $10 to the UPS bill, I get angle at home depot. The electrical hookup used 12 gauge wire (red & black) and .157" bullet crimp connectors, also forks, from Dorman at the oreilly's auto supply. I installed a 30 amp fuse in series with the battery, an AG3 in a littlefuse holder from dorman. Put the male on the + and the female on the - to avoid interchange in the dark. I just tied the wires to the frame with tiewraps, it is messy but not unreliable. I leave my bike out in the rain all the time, the only problem is really heavy downpours will de-activate the throttle. It has to be blown out afterwards with a hair dryer.
Living without a car is good for the environment, IMHO. Have fun shopping electrically.

 

[Katysax]

That’s very helpful. Thanks.