Mounting a 2nd, small battery to power lights?

[Vailen]

Has anyone attempted to purchase a small, 2nd battery and power their headlights, taillight, and/or other lighting with that 2nd battery? I have found some small batteries like Bicycle Motor Works' Pocket Rocket but am unsure if this could be used to power any lighting accessories directly.

Does anyone have any insights, experience, or feedback? Greatly appreciated.

 

[HumanPerson]

Get ahold of Matt there if you can talk to him these days, he would know what you'd need and would possibly build it for you.

https://bicyclemotorworks.com/contact-us/

I've known Matt for years, he's a good guy and will work with you if he can.

 

[Vailen]

I sent Matt an e-mail. In the meantime, I am wondering if anyone has ever tried this.

 

[HumanPerson]

Quite a few people do it, some just use a drop down converter, others go a bit deeper.

Some good ideas in here:

https://www.youtube.com/results?search_query=using+a+52v+ebike+battery+to+power+headlight+and+taillight

 

[DieselTech]

I run a seperate battery for my lights, turns signals, horn & some other stuff on a bike of mine. I just got to charge the add on battery from time to time. I also used all LED lights to keep battery draw low.

 

[Vailen]

I would be very interested in learning more about your setup. I have not purchased anything yet and would like to purchase the ideal headlights, taillight, turning signals, side flashers, etc. I live in New Jersey, and I light up my current e-bike like a Christmas tree given the intense traffic conditions we have here, and I also mainly ride at night. Multiple lights are a necessary safety requirement for me.

When you have some time, could you post details on your setup? Thanks.

 

[DieselTech]

I would be very interested in learning more about your setup. I have not purchased anything yet and would like to purchase the ideal headlights, taillight, turning signals, side flashers, etc. I live in New Jersey, and I light up my current e-bike like a Christmas tree given the intense traffic conditions we have here, and I also mainly ride at night. Multiple lights are a necessary safety requirement for me.

When you have some time, could you post details on your setup? Thanks.

Yeah I can get you some details. This setup of mine does add a lot of external wiring, but it is only related to the lighting. I am using all motorcycle components, switches & lights.

 

[Vailen]

Yeah I can get you some details. This setup of mine does add a lot of external wiring, but it is only related to the lighting. I am using all motorcycle components, switches & lights.

Many thanks! Your setup sounds like exactly what I want to do. Managing the external wiring will be a major challenge, but I will figure that out when the time comes.

 

[DieselTech]

Many thanks! Your setup sounds like exactly what I want to do. Managing the external wiring will be a major challenge, but I will figure that out when the time comes.

Yeah on wire management a guy can use poly- loom & hide most everything. You can get poly loom in different colors if a person wants to color match.

 

[DieselTech]

I wonder if a guy could hack this kit. It would save a lot of wiring & sure clean things up on the wire management side. They have came out with some nice kits since I've done mine. Lol some of sxs kits look good too.

 

[Vailen]

I was going to say, "Yes! You found it!" until I saw it's for BBS01/02. LOL!

 

[Vailen]

DieselTech...when you describe the details of your setup, do you think you can post some pics of your e-bike? I would enjoy seeing the work you did up close. Thanks!

 

[DieselTech]

DieselTech...when you describe the details of your setup, do you think you can post some pics of your e-bike? I would enjoy seeing the work you did up close. Thanks!

I can post some pics. But it's not a ebike. It's a gas bike with a small honda engine & gearbox.

 

[Vailen]

I can post some pics. But it's not a ebike. It's a gas bike with a small honda engine & gearbox.

Did I read that correctly? I think you are the first person I have met who owns a true hybrid: a gas-powered e-bike!

 

[DieselTech]

Did I read that correctly? I think you are the first person I have met who owns a true hybrid: a gas-powered e-bike!

No the hybrid side is not done. It's a straight up dinosaur sipper gas bike. I like building motorbikes, & just joined this community. I'm waiting on my ebike yet. It was a pre-order.

 

[Vailen]

No the hybrid side is not done. It's a straight up dinosaur sipper gas bike. I like building motorbikes, & just joined this community. I'm waiting on my ebike yet. It was a pre-order.

Now I understand. Still...you are definitely proficient in the DIY part, much better than I. I have not purchased my long-term e-bike yet nor any accessories (I have a starter fat e-bike for now). If I can learn from you, I will map out an electrical diagram that accurately details all the connections and connectors needed to connect a 2nd battery that will power only the lighting accessories. The DC-to-DC converter to drop the voltage is an important piece I am learning about today. If we can use motorcycle lights, turning signals, etc., then the number of accessories available for an e-bike quadrupled.

 

[DieselTech]

Now I understand. Still...you are definitely proficient in the DIY part, much better than I. I have not purchased my long-term e-bike yet nor any accessories (I have a starter fat e-bike for now). If I can learn from you, I will map out an electrical diagram that accurately details all the connections and connectors needed to connect a 2nd battery that will power only the lighting accessories. The DC-to-DC converter to drop the voltage is an important piece I am learning about today. If we can use motorcycle lights, turning signals, etc., then the number of accessories available for an e-bike quadrupled.

Yes if you run a small 12v battery you can have a stand alone lighting kit. That does not effect the ebike side of the wiring. No cutting or splicing on the factory ebike wiring harness.

I'm no ebike technician yet, but I am a 25+ year certified automotive/diesel technician. I think we can get something figured out.

Really the only thing that puts a restriction on your lighting, is how big of battery you what to add & carry.

 

[DieselTech]

Does your bike have any lighting now? Like a headlight & a brake light.

 

[Vailen]

Does your bike have any lighting now? Like a headlight & a brake light.

Yes. I have an integrated headlight that came with the bike. But I do not plan on making any improvements to what I own now. In early 2024 I will be buying my dream bike, then adding a motor and battery, then adding a 2nd battery (if possible) for powering the following:

(1) 1 front main headlight
(2) 2 front satellite headlights (fog lights)
(3) 1 or 2 rear taillights with integrated brake lights
(4) front turning signals
(5) rear turning signals
(6) side flashers

Ideally, I am trying to recreate all the lighting we see on motorcycles. I have no idea how I am going to do this yet, but I have many months to slowly spend time figuring this out. My intention is to map out all the connections on paper first, as well as calculating the power requirements and ensuring the battery can handle the power draw. With the right DC-to-DC converter, I could purchase a higher capacity battery with higher voltage and step down the voltage through the converter, which will enable me to power the lights for a longer period of time. The pocket rocket is amazingly small; I may have room to mount 2 of these.