TongSheng 500W Conversion on 2004 Giant Cypress LX

[bascherz]

My first e-bike was a Surface 604 Colt, which I absolutely loved (and now my neighbor does!). But I should have researched motor kits before buying it as I had a custom-fitted 2004 Giant Cypress LX hybrid I love that was just sitting there being ignored. So I did some research (you know, modern day research...a lot of reading here on EBR and also lots of YouTube videos). I was initially drawn to the Bafang mid-drive kits from Greenergia on Amazon. But those are cadence-sensing motors. I found out the TongSheng mid-drive motor is torque-sensing, and reading more on it I got opinions about the "feel" of this versus cadence. I've now ridden both, and the difference is pretty easy to describe.

• With cadence-sensing all you have to do is rotate your pedals and the drive kicks in at whatever PAS level you have selected. It feels like someone is pushing you along at the top speed that PAS level will propel you without pedaling. You do not have to expend any effort and you will move.
• With torque-sensing you have to do work. And the motor (at least the TongSheng) multiplies your human output power based on the PAS level you select. I don't have exact specs on what the multipliers are, but it's something like on "ECO" the motor adds 50% of the power I am expending. "TOUR" seems more like 100%. "SPEED", maybe 150%. And "TURBO" like 200%. It makes you feel like Lance Armstrong even just set on "TOUR". You just feel more powerful than you actually are, but you don't move unless you work.
• Both motor kits (as well as the hub-drive Surface 604 bikes) have a throttle if you just don't feel like pedaling.

I bought the TongSheng 500W kit from Greenergia off Amazon with a 500W motor and 12.5Ah downtube-mounted 500W battery at just under $800. The kit is nearly complete, though it doesn't come with a headlight or taillight. I added rechargeable LED lights for those. There were no display options with this kit. My Giant had integrated brake levers/shifters, so because the kit comes with brake levers with motor cut-off switches, I decided to use them. That meant I had to buy a replacement rear shifter ($30 at a local shop; had to buy a pair). The kit includes a motor bracing bracket that clamps on just behind the bottom bracket, where my kickstand was mounted. So I also bought a new chainstay-mounted kickstand ($15, Amazon). I also decided to make this bike an official commuter and added some very cool fenders. I needed to buy some tools to get the job done, mainly to pull the crank from the bottom bracket ($20, Amazon) and a pack of zip ties for cabling (only 2 came with the kit, for the speed sensor).

The build took me around 10 hours over 4 evenings, spread out as I waited for tools and some tech support from Greenergia (which is excellent, by the way). That includes the fenders, which alone took about 90 minutes. I ran into a few issues that I saw resolved in some of those YouTube videos, so I was ready before I started.

The bike got a good cleaning in the process, and the results are in the attached photos. I love the way this bike rides, so much that I sold my Colt as mentioned earlier. I am 6'5" tall and about 240 lbs and I am getting around 80 miles on a charge riding a mostly flat trail (there are hills, but not big ones) keeping it on "TOUR". I estimate I could get 100 miles on "ECO", but I haven't tested that theory.

I am absolutely thrilled with the result of this build and would recommend this approach to anyone mechanically inclined and patient enough to do the conversion. It's not trivial, but it's not super difficult either. All in all, this project cost me $550 for the bike (in 2004 at Performance), $780 for the motor kit, $30 for a shifter, $45 for lights, $34 for fenders, and $15 for tools. So the total cost of this home-converted bike was around $1455. The Colt was $1899 to my door and though it is a really great bike, I like this conversion much better.

Links to what I bought. Don't check my math, please.

• Motor kit: https://www.amazon.com/gp/product/B07QS8YD2K
• Tail light/brake light: https://www.amazon.com/gp/product/B07J1WLLX4
• Head light: https://www.amazon.com/gp/product/B077B3WYXC
• Kickstand: https://www.amazon.com/gp/product/B01LZG89ZG
• Fenders: https://www.amazon.com/gp/product/B01N2374CG
• Fork fender stays: https://www.walmart.com/ip/SKS-Bicycle-Suspension-Fork-Fender-Stay-Attachment-Clamp/293089843
• Water bottle strap: https://www.amazon.com/gp/product/B00ZFHW1MI
• Cable coil wrap: https://www.amazon.com/gp/product/B009IPFOFO
• Control cable ends: https://www.amazon.com/gp/product/B07TWHB578
• Chain tool: https://www.amazon.com/gp/product/B07FFW7SMD
• Crank puller: https://www.amazon.com/gp/product/B0716NX7KC
• Shifter: SunRace M50 (bought locally. see photos)

I am happy to answer questions if I can.

Happy riding!

 

[Ravi Kempaiah]

Looks very clean!
I love that you transformed the bike and putting into good use.

 

[TakO]

I got a TSDZ2 for my wife and I'm attempting to mount it to her Giant Cypress. I hit my first snag. (By this point on my first conversion, I had hit several tool-related snags, so I felt pretty good about this one.) Unfortunately, the shifter cable for the back is held right under the bottom bracket with a plastic piece that has a groove in it. That appears to be hitting the motor when I tried to slide it on.

UPDATE: I got a low-profile cable guide on Amazon. I still had to shave it down with a Dremel and get a shorter screw with a flat head.

After that frustrating pause, I got it all worked out. I'm happy with the results.