Electrical Smuggler

[Ludwig61]

Hello!

I ride my FJR as a support vehicle for bicycle charity fundraising, such as the BP MS 150 - https://main.nationalmssociety.org/site/TR/Bike/TXHBikeEvents?pg=entry&fr_id=28263 - this weekend (13,000 bicyclists, which will raise about $16million for MS research).

Forgive my lateness in posting my plans for others to review.

The basic idea is to replace my rear seat with an auxiliary battery, fuse box for/to blinky lights, and a mobile ham radio setup.

Wiring will be battery to battery with 40A inline fuses close to each positive terminal. In addition, there will be a switch between the fuse and the auxiliary battery as my choice of battery isolation. When I stop, I turn off the connection. After I start, I turn it back on. I have a better solution - https://www.discovercircuits.com/H-Corner/bat-iso.htm - but it needs a PCB designed and two built....

Positive on the auxiliary battery runs to 1) a switch and then a fuse box for the four blinky lights (3A each); and 2) a switch, an inline fuse, and then a Kenwood TM-V71A (3A listening, 13A broadcasting at full power).

My main battery is a Shorai LFX/Lithium. It is a different chemistry from the consumer batteries in phones and 18650s and such. Since the voltage parameters are different than lead-acid, I bought another as the auxiliary. Because they run higher voltages than lead-acid, I couldn't use a standard battery isolation setup. The auxiliary battery states it can take 7A during charging and is equivalent to a 7Ah lead-acid battery.

So during riding, I'll be running the blinky lights and listening to the radio (through Bluetooth powered by the radio) with everything connected. When I stop to help a bicyclist, I will be cutting the connection between the primary and auxiliary and turning off the bike. When I'm not on the route, I'll be turning off the blinky lights and maybe the radio.

Is this basically sound? The repair manager at my local Yamaha shop never has anything good to say about any deviation from original parts, so I'm not sure I can trust his recommendation (don't do the radio at all, the blinky lights are probably ok, the battery chemistry is seriously problematic, and pull fuses rather than wiring a switch).

Thank you for your time and assistance!

 

[garyahouse]

One thing to be careful of is that Shorai's don't like to be discharged below 13.1 resting voltage. Their website says that below this, they need to be recharged. You didn't mention this, so... you might want to hook up a Datel or similar type of voltage meter on both of your batteries to keep an eye on the voltage. Shorai's aren't cheap and ya don't wanna toast one of them. As you probably know, Shorai's do not function well in a deep cycle application. Not sure how long you want this second battery to work without sufficient charging.

You're running a Gen 1 so the max wattage the bike can generate is 490 with about 120 watts to spare over what the bike uses with no extra add on accessories according to the info provided here: CLICKY

Hope that helps??

You said the Kenwood uses 13 amps at full power. How long do you plan to use this at a time using this level of power? That's a lot of watts, about 156 watts if my math is correct. This is well beyond the extra wattage your alternator can put out so I'm wondering how long you can keep up that level of usage, especially if the engine's not running and you're using a 7ah auxiliary battery. A battery designed for a deep cycle application might work better for your auxiliary battery in this case. Again this depends on how hard you are going to work the second battery when it can't be sufficiently recharged right away. I assume your primary battery is the Shorai 18 amp/h model? That's the one Shorai recommends for the FJR. Your auxiliary battery looks kinda wimpy by comparison, but I'm gonna guess that a few seconds of broadcasting shouldn't be an issue. The voltage meter will tell you what you want to know. While broadcasting, you'll see your voltage drop. Then once ya stop, you'll see it slowly climb back up over the course of 15 seconds or so. Once it fails to reach 13.1 volts on this "rebound" voltage, it'll be time to stop using the battery. I've tested these batteries down to 12.9 volts and found them to survive, but I wouldn't recommend it.

Gary

darksider #44

 

[redneckj]

You can also use a WPS featherweight battery. Like this one.

https://www.amazon.com/WPS-Featherweight-Lithium-Battery-HJB7B-FP-IL/dp/B00DX8993A

 

[Fred W]

There are some problems with your plan, probably stemming from a basic misunderstanding about what batteries can and can't do..

Batteries are not sources of electrical power. They are merely storage devices for power that has already been generated. So what you will be doing is charging up the second battery while riding and then deeply discharging the second battery to run your accessories, etc. when you stop to assist. Repetitive deep discharging of any battery is not good for the battery, and the very heavy load you'll be placing on your alternator afterwards to recharge the dead battery is not good for your alternator and regulator/rectifier.

You could entirely avoid the need for a second battery just by keeping the bike's engine running, and the alternator generating power, when you stop to assist a cyclist. That is what I would try to do if I needed to keep a bunch of electrical devices going while on the side of the road. The liquid cooled engine will not mind being idled.

I hope this helps. Good luck with the charity ride.

 

[Ludwig61]

garyahouse:

I'm starting to think I should switch back to lead-acid. At least there are nominally deep-cycle batteries of that variety. Weight really isn't an issue as the seat pan can support an adult.

I don't expect to talk more than a few minutes total, during an event. My Sena 20S was spectacular in a Shoei, but isn't as good in my Nolan. So if everything works like I want, I still may have to slow down to talk and be understood. I have the 18A as my primary. But with no depth, it isn't going to do what i want.

I have had it so low i had to be jumped. Given what I'm finding out, I'm glad it still works.

Redneckj:

That's basically what I have. But if the chemistry is different, it could cause problems by inducing one battery to charge the other all of the time. That's why I bought a second Shorai.

Fred:

It's actually worse than that, at least for a Gen I. The claim is that Idle doesn't generate enough electricity to run the bike - https://www.fjrowners.com/forums/9-fjr-technical/8905-upgrade-std-fjr1300a-stator-rectifier.html - see second post. I've had one person tell me the only bike that charges during idle is a Goldwing. Those will generate 1100 watts and use an alternator that is like a car's. Not sure what is usable surplus....

 

[RossKean]

Your lights and sound system are sucking back a very large amount of power. 12 amps for your blinky lights and 3 to 13 amps for the sound system - up to 25 amps total (300 watts). A fully charged motorcycle-size battery is around 12 ampere-hours so your system could run it flat in as little as 30 minutes of operation (depending on the amount of full-power broadcasting). Even if you have a deep cycle battery that can take this abuse, it won't last long enough to be very useful and the bike's charging system can't possibly make it up - even at considerable engine speed. (Are the blinky lights 3 amps average or only when blinked on? might make a fair difference)

Perhaps you could find some low wattage (LED) lights as well as minimize the "power on" time for the sound system? If you can get average power demand down to 150 watts and keep the engine running (and revved above 2500 rpm), you might get away with it. At least getting to the point where it will just slowly die over a period of several hours so you could accomplish your "mission".

Either that or find a spot for a little Honda generator to take along for the event. Maybe a REALLY long extension cord?

Good luck!

 

[garyahouse]

Was Ross right when he assumed the blinky lights are NOT LEDs? His LED idea might be a big help. Much less amperage.

Anyway, again, maybe you should consider getting a deep cycle battery for this second battery. Based on what you described, a Shorai will die in a hurry when subjected to that kind of abuse.

If the using your system rendered an 18ah Shorai unable to start your bike, that little 7 amp that you have might not hold up to well. Did I understand you correctly? Your second Shorai is 7ah?

Another thought: do you have a throttle lock? You can keep the engine idling fast so it'll charge better.

Again, ya need a voltage meter (or two). Then you don't have to guess any more. If you're worried about the price, Ebay's got gobs of them el cheapo.

Based on the info you've given, it's likely that an 18 amp deep cycle will meet your needs, especially if you can charge it some while riding. Any options of riding in a lower gear to keep the revs up? That'll produce extra charging amps...

 

[Ludwig61]

World:

The project is being revamped to use lead-acid batteries.

Ross and Gary:

The blinky lights are high intensity LED strobes. So they likely aren't all on a significant percentage of the time for most/all patterns. Each head is 4 LEDs. Each LED is a claimed 5 watt LED, and I believe it (I've had 3W flashlights for years).

The auxiliary battery is not yet size constrained. I'd like to find a heat tolerant deep cycle battery. I think the best I can do will be an AGM deep cycle. It will sit on the rear seat pan. Since it will be restrained in a pod/smuggler that is built off the rear seat pan, I do have concerns about smuggler integrity failure from the force of hard braking, etc., that will constrain the weight I choose. If I am stopped, I am more likely to be broadcasting. In fact, I'll almost never broadcast without already being stopped. I'm figuring I want to last at least half an hour, talking at least half that time. So 18Ah is ok if the battery and bike can cycle that deeply.