EVr in suburban NY


New Member
Pearl River
A 5th generation Californian, I moved to NY in 2016, leaving the home I built in Topanga Canyon, retiring from my work as a motion picture production designer, to help care for my infant granddaughter. I sold my wonderful VW TDI Jetta Sportwagen back to VW, and used the proceeds to buy a 2013 Nissan Leaf with 20 kmiles from a among a glut of them coming off leases. This fantastic little car (45 kmiles later all it has needed is a set of tires, windshield wipers, and its little accessory battery) made me a big EV fan.

So after my knees gave out, making my lifelong love of cycling difficult, I decided to convert one of my bikes to an mid-drive ebike. My daily rider was a spectacular Trek Soho with a Shimano Nexus 8 and a Gates belt drive, but it has an earlier belt design which is very sensitive to its "chainline" which I was not sure I could maintain with a mid drive kit, so I demurred.

Finally, when my granddaughter sized out of the sweet little Bobike front-mounted child seat and into a rear-mounted seat, I realized that with the rear child's seat, I could no longer swing my leg over the seat to mount the bike, and with my knees and the standard men's diamond frame, I could not get on and off the bike safely. So, I took the step-through-frame Electra Townie 3i I had bought for my now deceased sister, and installed a Tong Sheng TDSZ2 48 V 750 W mid-drive kit.

Sadly the battery I bought did not fit between the curved downtubes, so I mounted it on top of the upper down tube. This blocked the step through, raised the center of gravity, and was horribly inelegant. With great trepidation, I decided to remove the aluminum base and use a heatgun to soften the battery's case to (de)form two dimples into the case to fit the curved downtube and engage around a small gusset joining the head tube and down tubes. I used a standard worm drive hoseclamp to mount a small aluminum angle to hold the battery's dimple engaged in the gusset and small strap to further secure it. I was pretty surprised how well this sort-of funky hack worked out, and have put a several hundred miles on it over all sorts of terrain with no problems at all. It is a bit harder to get the battery on and off the bike, but I just charge it in place.

I got a boot loader and installed Open Source Firmware developed by Casainho and others on the Endless Sphere forum. Sadly, it has a still unresolved issue where it delays before restarting assist after a pedaling pause, such as to shift on a hill. I love the additional information the OSF can display, but my daughter, with whom I share the bike, doesn't pay any attention to to the data and hates the pause even more than I do, so have returned to using the stock firmware.

I really love this bike and the TSDZ2 torque assist system, and am looking forward to eventually figuring out how to solve the chainline issue (and be able to afford) to install one on my Soho.


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Staff member
Wow, what a great story @Nesdon. It sounds like you got the VW settlement thing like my friend @Chris Nolte. Great choice on the Leaf! I see them around, and love the new design for 2020 or 2021, and they seem like some of the best value electric cars. Glad it has worked so well, and thanks for choosing a cleantech car to keep the air fresh and promote investment into sustainable transport ;)

I've heard of Topanga Canyon, is it famous for anything? What was it like working in the movies, did you get to meet some famous people and hear about their adventures?! I got into ebike for the same reason as you, because my knees are sensitive and probably damaged from skiing and snowboarding growing up. I haven't had any surgeries, I just try to be gentle with them these days.

It's interesting to hear about the early day belts, and I can see how Gates updated their design with the CDX center track, to keep it from edging from side to side. Did your older belt have any sort of retention design like this, or was it just completely flat toothed cogs with no borders or track?

I don't know a lot about the Tong Sheng mid-drive motors, but it looks pretty good on your Electra Townie! I'm AMAZED by the modifications that you designed to fit the battery. As someone who likes designing and building things with my hands, I now applaud you with them :D It sounds like you've had a lot of experience, having built your own house too. Not only is your new battery position easier to stand-over on the frame, but it also keeps the weight lower for improved handling. Nice job with the heat gun and pipe joiner thing with the L bracket. I'm not sure I'd be brave enough to use a heat gun near Lithium-ion battery cells (known for catching fire), did you do the mod to the case with the plastic separate from the actual cells? Nice little buckle strap too... it's definitely DIY, but looks pretty good. I love Endless Sphere and it's sooooo cool that you can actually modify software for some of the kits and stuff. I noticed that Bosch systems recently migrated the rear wheel magnet and sensor near the dropout, so the speed dongle attachments won't be as easy to clip on as they used to be. Anyway, I enjoyed your post and wanted to welcome you here!