Giant Quick e+ 2018 (and later?) lighting HOWTO with a Lupine SL light


New Member
I have a Giant Quick e+ 2018 and wanted to upgrade my light with a Lupline SL. It's a yamaha syncdrive sport system with a custom wiring setup that is a bit different than other e-bikes. The Yamaha cable doesn't work because it comes with a male connector but the giant needs a female connector. Fortunately, the Giant comes with a stock light that has an existing cable. You do NOT need to take out the engine to get at the wiring harness. What I did to make this work:

Tools you will need: screw drivers, lighter or heat shrink gun, soldering iron, heat shrink tubing (mixed sizes)
  1. Pull the existing light wiring out of the downtube until the JST connector is visible.
  2. Pop out the JST connector using a small screw driver.
  3. Using a wire cuttter, cut off half of the existing wiring. You want the part with the female JST connector.
  4. Cut off the male end of the JST connector on the Yamaha wire ( ).
  5. Install the new cable in the lupine light following the directions on the packaging.
  6. Install the light. In my case I had to move the Giant / Yamaha LED screen to make space for the light.
  7. trim the light cable to the desired length.
  8. Expose the red / black conductors using a wire stripper.
  9. Get a package of heat shrink. Heat shrink provides a water proof seal on wiring. You can shrink the heat shrink using a lighter.
  10. Get a larger piece of heat shrink and put it over the cable. This is so you can shrink the entire cable in step 14.
  11. Cut some smaller pieces of heat shrink and slide them over the black and red wires.
  12. Solder the black to black, red to red
  13. Using a lighter or heat gun, shrink the heat shrink around each conductor.
  14. Slide the larger heat shrink over the two conductors. Using a lighter or heat gun, shrink the heat shrink.
  15. Plug in the JST conductor into the Giant wiring. Push back into the downtube.
  16. Turn on the power and enjoy your new light!
Note: Steps 7-14 can be done off the bike!!

The SL is a vast improvement over the stock light. It's brighter, has a cut off similar to automobile lights, focuses the light on the lane, and has automatic blinking daytime mode.

I did search around for a cable that had the right connectors and couldn't find one. It's possible that Giant and/or Lupine will start making the correct cable. It's also possible that you could purchase the JST connectors and a crimping tool and make the cable correctly without splicing. I just didn't know how to do that.
Last edited: