Advice for converting tandem

Harly

New Member
#1
I am looking at adding a front hub kit to a tandem. The tandem is Raleigh frame with 26 " wheels. In trying to keep weight balanced I am considering a front hub motor. Would 500W with 36v battery be ok? I live in Salt Lake City--I ride some hills. I would not consider taking this up the canyons. Most rides are about 2 hours.
Thoughts anyone?
 
#2
Just to give you a idea what I did when I built the wife a bike last year. Used a battery from Luna https://lunacycle.com/48v-panasonic-ga-17-5ah-black-killer-whale-ebike-pack-huge-range/ and the front wheel kit from https://www.aliexpress.com/item/Who.../1947983314.html?spm=2114.13010608.0.0.2HJDYe with no issues. From the picture you can see I placed all the wires and controllers in the front basket and than added a piece of thin wood so the basket is still half usable. The battery is on the rack in the bag. I just bought a heavy duty power cord to use as my plug, one end connected to the controller and the other end remained a standard plug. Connected a outlet to the battery so just plug in the battery when you are ready to ride, easy. With two riders and a hill or two I would say the bigger battery and 48v to get a full two hours. This will vary a lot on how much each of you pedal. The link I sent is for a 1000 watt but this would be the same as a different manufacturer who says it is a 500 watt. I do not find it over powered at all and we are heavy riders, rather have the power than not and plus no motor stress. You can also limit current and speed anyway with the display. My second bike is labeled 500 watts and has the exact same wattage on display. Also would suggest a http://www.ebikes.ca/shop/electric-bicycle-parts/torque-arms/torqarm-v2.html# to keep everything from moving on the front wheel. Wife does not have the disc brakes either and is doing fine but would of been nice to have disc brakes for stopping just to be a little more in control.
 

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Harly

New Member
#3
Just to give you a idea what I did when I built the wife a bike last year. Used a battery from Luna https://lunacycle.com/48v-panasonic-ga-17-5ah-black-killer-whale-ebike-pack-huge-range/ and the front wheel kit from https://www.aliexpress.com/item/Who.../1947983314.html?spm=2114.13010608.0.0.2HJDYe with no issues. From the picture you can see I placed all the wires and controllers in the front basket and than added a piece of thin wood so the basket is still half usable. The battery is on the rack in the bag. I just bought a heavy duty power cord to use as my plug, one end connected to the controller and the other end remained a standard plug. Connected a outlet to the battery so just plug in the battery when you are ready to ride, easy. With two riders and a hill or two I would say the bigger battery and 48v to get a full two hours. This will vary a lot on how much each of you pedal. The link I sent is for a 1000 watt but this would be the same as a different manufacturer who says it is a 500 watt. I do not find it over powered at all and we are heavy riders, rather have the power than not and plus no motor stress. You can also limit current and speed anyway with the display. My second bike is labeled 500 watts and has the exact same wattage on display. Also would suggest a http://www.ebikes.ca/shop/electric-bicycle-parts/torque-arms/torqarm-v2.html# to keep everything from moving on the front wheel. Wife does not have the disc brakes either and is doing fine but would of been nice to have disc brakes for stopping just to be a little more in control.
Thanks for the feed back
 
#4
Front hub works great on a tandem. I have a Grin All Axle gearless direct drive hub motor driving the 20" front wheel on my bike friday tandem. That system is at 52v and 750w, rather high end.

With the larger 26" wheel on your tandem, I recommend a large geared front hub motor, with 500-1000 watt rating. Choose voltage to suit your desired top speed. Good motor choices are the MAC, EZEE, or BMC, which are basically the same. Ebikes.ca or em3ev are excellent vendor choices, I've used both. Ebikes.ca has some great calculators available.

My area is Denver burbs. We have some hills, my commute has several 4-8% grades. I appreciate the full legal maximum of 750 watts when climbing.

This kit from EM3EV kitted out with a front wheel build, battery, and basic throttle control only would run about $750 + shipping. https://em3ev.com/shop/mac-kit-47v-battery-900-1200w-max/

Expect your bike to gain 8 pounds from the motor, 8 pounds from the battery, and about 1-2 pounds from the other stuff that goes with. If you like to tinker around, spring for a Cycle Analyst V3 to be your dashboard, you will be better equipped for future tinkering.

For a tandem, there is a good argument to be throttle only vs pedal assist. That is that the stoker can pedal the bike when you dont expect it. With just stoker power, that is a mild issue. But if the stoker makes the ebike take off, you might have issues. However, with a CA V3 you could include an aux input to adjust the pedal assist, manually moving it to zero when coming to a stop or going slow; or having a minimum speed before PAS starts.
 
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