I recently got a bike with a Yamaha PW system. The bike computer has a light on/off button but the bike itself has no light and I want to add one. How do I do this? From what I understand, I need a light cable, some sort of crank pulling tool to open the motor, plus the light itself.

My question is where can I learn about the detailed procedure for doing this?

  • At that link there's no obvious detailed picture of the computer you mention. But I'd start looking there, at the switch. I very much doubt you need to open the motor itself or remove the cranks to access the electronics, though there may be an electronics housing nearby
    – Chris H
    Nov 15, 2017 at 6:53
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    Its an add-on The keyword to google is "lupine" along with Yamaha pw ebike light. Be prepared for price shock - a front one costs twice as much as my road bike, and comes with no cable. Then you need a back light too!
    – Criggie
    Nov 15, 2017 at 7:22
  • I don't think you need a special light, the hard part is figuring out where the connection is and its voltage. There are a lot of lights accepting wide range of voltages. It seems online for Yamaha PW system is hard to find.
    – kiwi
    Nov 15, 2017 at 11:40

6 Answers 6


Okay, so I did some research into this and here's what I found:

  • The Yamaha drive offers enough power for many, but not all, ebike lights to be connected. For example, Supernova M99 Pro won't work -- that's my favourite bike light. But lights like the Lupine SL S or Supernova M99 Pure work just fine.
  • To install the light, one needs to remove the protective plastic cover and undo two out of three bolts that connect the motor to the frame.

So I've ordered the light and the Light Cable to connect it to.

Update: did the entire installation process, here are the approximate steps I had to take.

  • Step 1: remove motor cover. Also the step where I get unpleasanly surprised that the bottom plastic motor cover has a hole in it. I wonder what idiot thought of that... this is where all the dirt and mud will accumulate. This is insane. Reminder to self: tape it over. Haven't seen this level of insanity from Bosch.
  • Step 2: unscrew two out of 3 motor bolts, loosen the third... also the step where I realize that those bolts are tightened with 22Nm of force. I did not, do not, nor will I ever own any instrument with a hex key that can apply 22Nm of force. This seems excessive and downright cruel and no, Bosch does not do anything as evil. Consequence: had to improvise a long handle for a hex key. Pretty sure I did not tighten it back to 22Nm, but I don't care. It's not going to fall off.
  • Step 3: connect Bosch LightCable to the motor (there's no ambiguity regarding the port or direction) and run it to the handlebar. This was also annoying because Haibike has these black plastic plugs where the wires came out and naturally, there's no space for extra light wire. Had to clip away some plastic.
  • Step 4: connecting wire to Luping SL S light... where I found out that Lupine does not mark the type of screwdriver you need for opening up the light. Furthermore, I watched their video where they suggested a Torx T5, so I ordered one, waited two days only to find that the light actually opens with a T6. Insanity! Also, they ignored my support request :( and when a manufacturer does that, well, they get blacklisted in my book.

To sum things up: the process of light installation is rather annoying, but manageable.

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    When you get it all working, do please come back and expand this answer to tell everyone how it went. You can also mark this answer as accepted because its what worked for you.
    – Criggie
    Nov 16, 2017 at 3:53
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    @Criggie done!! Nov 29, 2017 at 20:46
  • Well that 22Nm is tricky as my torque wrench starts at 30Nm.. yes it is for automobile use. Hopefully you did not tighten those screws with excessive force as they are attached to aluminium and you probably end up destroying your frame... otherwise took me less than 20min to do this. And plastic clip for two wires shoud be purchased beforehand...
    – user44937
    Aug 17, 2019 at 17:30
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    Holes in casing lower sections are generally to let water out. Tape over it at your peril! I have had bosch motors for service where the whole outer casing is stuffed with muck that couldn't escape.
    – Noise
    Aug 2, 2021 at 8:00

OK, just added Lezyne E50 and Hecto rear fender lights to a Giant Lafree E+2.

That is these lights: Lezyne E50 Lezyne Hecto Rear

Like others have said, remove two motor mount bolts and let it pivot on the third bolt: Giant Lafree motor swung down to access wiring

Then pull down the connectors out of the down tube; this shows two unconnected connectors; a three pin and a two pin rear light connector (JST 02R-JWPF-VSLE-S 2 pin receptacle) with a white (+6V) and a grey (GND) wire: Rear light port shown circled

Note you will have to remove the white rubber cover before connecting to this two pin connector. You will have to draw the wiring further down the down tube to reach the front connector; its near the round handlebar control plug right up at the top shown with my light (yellow and black wires) connected: Front JST 2 pin connector for front lights

After pulling the wires down the down tube for front light, and following the wiring up fender for the rear, then it just remains to terminate the wires grey to GND and white to +6V with a 2 pin JST JWPF plug (02T-JWPF-VSLE-S) using JST SWPT-001T-P025 crimp pins: JST JWPF 2 Pin Cnnector JST SWPT pins

Put your bike back together, and now the lights work from the front handlebar switch!

... hope someone finds this useful.

  • Nicely documented - thank you and welcome to the site !
    – Criggie
    Apr 27, 2020 at 7:38
  • Just to confirm, there is a separate connector for front and rear lights and each one is terminated with a 02R-JWPF-VSLE-S? So if I want to add both front and rear lights, I need to order two 02T-JWPF-VSLE-S terminals?
    – Jared
    Jun 14, 2023 at 16:18

So this is pretty straightforward on the Giant Roam E+.

There is a wire harness that you can access at the top of the frame just below the battery. There is a small cap. In there you'll find three wires. One is a mini style jack to connect the control switches. The other two one is yellow/gray and is 6 volts switched to the light switch, the other is purple and black. This wire reads 40 volts DC, stay away from this one, not sure what it does but it is live all the time, even with the battery removed (I suspect for a short time only) it still has voltage.

The Lezyne light is about 7 watts and the tail light about a watt and a half. The limit for this circuit is supposed to be 9 watts.

I know there are harnesses out there to plug directly into this connector, but splicing is easy if you have the right tools and connectors.


You don’t need to loosen the engine. At least on my Ghost HTX 2020. It’s enough to take the bottom connection platform for the battery away.


What you're describing is totally possible, but I don't think its very practical. I suggest you buy a standard set of rechargeable bike lights from your local bike shop, or online. Installation should be pretty self-explanatory. You just strap them to your handlebars, and charge them in once a week.

I personally use this light from NR.

  • 1
    Agreed - I'd rather run the main battery out of power and still have lights to pedal home by, and not run out of power for everything. Then again one of each type light is not overkill either.
    – Criggie
    Nov 15, 2017 at 7:16
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    Rechargeable lights are not an option. Bike lights don't draw that much power - I have a Supernova M99 Pro on my other ebike always-on, I don't even notice the power draw. Nov 15, 2017 at 9:10
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    @DmitriNesteruk additional Rechargeable lights are always an option. There's nothing wrong with independent redundant lights.
    – Criggie
    Nov 15, 2017 at 19:29
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    @Criggie it's the very act of having to recharge them when they are dead that's infuriating. you can remember to charge the bike and forget to charge the lights Nov 15, 2017 at 21:15
  • Well I did it, so it's not impossible. Dec 6, 2017 at 11:29

Not for nothing, but I'm pretty sure the hole is to let the grime, etc. come out.

My PW-X2 apparently doesn't have the light cable at all, so I am considering taking power from the display unit cable, but finding the right connectors for sale is a challenge at the moment.
Edit: I decided to take power from the battery to motor cable instead. You can see the details here if interedted: https://shiruba-technology.blogspot.com/2021/08/stealing-power-from-my-ebike-for-lights.html

Also, the Yamaha service manual states that 11Nm should be used. 22 seems 2x too high! Edit: 11 on one side, 22 on the other side. I put them in with less torq, and after about 20km of riding I started getting creaking sounds from the bottom bracket. Turns out they had loosened. So you should really follow the recommendations!

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