Hi all,
i have a 2001 EFI Road King. No real mods done to it. I had a small amp with handle bar speakers but I want to upgrade. I am worried about the electric draw being too much for the stator/voltage regulator to keep the battery fully charged.

I'm not an electronics guy. So I guess my questions would be:

1. How big of an amp/radio can I run?
2. Can the switched P&A plug under the seat handle that? If not what would the max watt amp that works on the P&A plugs/circuit? (It's a 15 Amp fuse)

Thanks in advance,
​​​​​​​Solo

 

Just install new amp and go. If worried about load consider better upgraded charging system from Cycle Electrics. Amp should be connected directly to battery and have it's own fused link and not to accessory plug. Also don't crank tunes while idling for period of time.

 

How do I run the Amp directly to the battery and have it "Switched" power with the Ignition?

I ran the power directly from the battery on my old bike and killed the battery everytime it was parked overnight.

 

Any decent amp should have a separate smaller gauge wire that connects to radio or ignition for power on. Usually blue if I recall correctly. There's the main larger 12v power in wire (usually red) with more than likely a 30a fuse then the smaller wire (blue) for ignition on. That smaller wire trips a relay in the amp that now allows power to flow through the larger red wire.

 

The 2001's had really poor quality stators - so bad that H-D pulled them for use only in carbureted bikes until stock was depleated. Most of them have failed by now and been replaced with the upgraded version. The bad ones had black paint on the windings and the windings were pretty wimpy looking.

If you are going to run an amp and want it to have a direct line to the battery, you could use a relay to the accessory plug. With a typical 5 leg relay that uses a resistor between 85 & 86 you could run the accessory positive to leg 85 and ground leg 86 (or vice versa it doesn't matter with the relay that uses a resistor in parallel between 85 and 86.) If the relay you pick has a diode between 85 & 85, polarity will matter.

You would then come off the battery + immediately into a fuse and then into leg 30.

Leg 87 would go to the amp+ and you would ground the amp to a good chassis ground.

87A would be left alone - not connected to anything. With the bike off, 87A would be hot but since it wouldn't be connected to anything, there would be no drain.

With this setup, when the accessory circuit was powered, the relay would activate and connect leg 30 to 87 which would power the amp. When the accessory circuit was not powered, the relay would not be powered and 30 would close to 87A which would be open and the amp would not be receiving power.

The fuse you installed would protect the entire circuit going into and coming out of the relay from the battery+

 

Great write up. This will be the setup I use. I just ordered a waterproof relay and harness with fuse. Hopefully, I can get this all set up.

 

Thank you. It should work great for your application.

 

You could also replace the lights with LED's and reduce the load on the stator that way. I don't think you need to worry about over driving the output of the stator with an amp though.

 

Once you've got your amp wired up and working you can your charging circuit at the battery, which will enable you to judge if all is well. You could then follow the LED suggestion if necessary.

 

Get a Bosch relay or something more reliable than Chinese stuff.