I'm having a Trek Super Deluxe Tandem 7i bike converted to electric as my wife has Alzheimers and has difficulty with strength and balance but still enjoys biking. I tho't a tandem would help us to keep biking longer.
Problem: the CargoBikeShop in Madison, WI is challenged with battery placement. The Style of the bike is basically a tandem beach cruiser with curves in the frame. The builder does not want to drill the frame and can't find a suitable device to attach the battery to the frame. He suggested mounting it on the back rack but I prefer not to use that location as it would raise the center of balance of the bike. I think as I will be the stabilizer to hold the bike during mounting and dismounting the weight of my wife and the battery on the rear rack will make it harder to balance the bike. At age 73 I don't need to encourage falling with my bike and a passenger!
Any suggestions as to how to attach the battery at a lower position?
pappaj@rocketmail.com
i just put grippy felt pads on the battery and use two heavy duty velcro straps, aint going anywhere. no drilling or mounting plates needed.
You could use some kind of bag/strapping assembly in that front triangle. I don't see any problem with drilling the frame. With the use of riv-nuts there is very little loss of strength. And that bike looks very well triangulated. As to the curves: simply use shims to support the attachment plate. BTW, my 17.5/48V battery is 14" long.
my recommendation is if most manufacturer batteries dimensions are too large to fit your frame, look into a custom battery thats smaller. https://bicyclemotorworks.com/ batteries are usually about 12 x 3.3 x 4" in size. see if that might fit in your frame.