Is a Larger Battery a possability

nokitov · Posted: May 25, 2009, 8:21 am Post subject: Is a Larger Battery a possability

Just throwing this out there cause I don't know. I hear a lot of talk about the XS electrical system being marginally effective. Running everyday and still needing to charge battery, recommendations to change coils because originals draw too much badly needed current, etc. Would a larger capacity battery help the system? I noticed that when I changed my original air filters to the newer pod filters that there seems to be alot more room for a larger battery. Or maybe add a second battery like they do in diesels to get extra amps especially for cranking. Should have enough room to add a larger battery box. What do you people with a better understanding of electrical sytems think? The main reason I'm asking is that I'm thinking of adding a radio to my fairing someday but from what I'm hearing this would probably be a bad idea at least from an electrical stand point.

pamcopete

nokitov,

Installing a larger battery does not mean that you can run extra electrical things withouit running the battery down. The power to run everything electrical on the bike has to come from the alternator, which produces 16 Amps @ 5,000 RPM, much less at lower engine speeds.

A larger battery will improve starting, however, but if you think in terms of a greater output from the battery, then it doesn't have to be larger. The AGM battery from MikesXS delivers more cranking amps with the same case size. It costs a little more, but not as much as a larger battery or two batteries would cost.

Radios do not draw a lot of current, so you could probably install a radio and would not have a problem. You could also replace the tail light with an LED model for a huge saving in current draw. More than enough to run a radio.

You will probably find that you do not have an alternator capacity problem if you change the brushes regulary and keep the rotor slip rings clean. It's a message that I and others keep preaching on the site. Most charging problems and run down batteries are caused by bad brushes. The minimum length spec of 1/4 " is way too short. 5/16 or 3/8 would be a better number.

nokitov

Thanks Pamco,
I know you know your electronics and that's reassuring about the radio. I like your idea for the tail light. While we're at it, my fairing has the rectanglular headlight. Any problems switching over to that style lamp..

pamcopete

nokitov,

Well, the rectangular headlight would probably be OK as long as you didn't use a high wattage low beam. The stock headlight is 40/50. 40 W low beam and 50 watt high beam. You could use a 55 or 60 watt high beam because the engine is at high RPM's when you use the high beam so the alternator could carry the extra load. If you install a LED tailight, then you could possibly go with a higher wattage low beam, except that you really have to keep it focused to avoid people flashing their high beam at you at night.

xsleo

I have converted all the lights on the rear to LED's. I also put in a converter to run the rear turn signals as brake lights as well as turn signals.
I run a headlight with a 55/60 watt H-4 bulb. If you run the higher output headlight bulb, make sure all the connections and the headlight switchs are clean and tight.
I also did pamcopete's Chrysler regulator and Radio Shack rectifier conversions. A great setup.
With this setup I get great lights and plenty of charging for the battery.
If you do up grade your lights and charging system you should have no problem running a radio. Most new radios draw only a amp or less. A large amplifier will draw more juice, so check for the current draw before adding one.

Retiredgentleman

Tell us what the battery voltage is at 3000 RPM.

nokitov

Pamco...XSLeo thankyou for your great insite and advise...the Chrysler thing is new to me. I should be able to do a search and find it.

RGM... don't know yet. I'm still closer to tear down phase than riding phase. My goal is to have everything back on and running by the week of June 22. School is still in session until June 12 and we don't finish until June 17. I'm guessing it's going to take me a good week to clean my garage, organize my tools, and find all the parts I've been carefully putting away. Like my dog hiding bones, they're in there somewhere.

bbjsw10 · Full Member Joined: Jul 15, 2009 Posts: 64

Closest post I could find didn't want to start new one.

y question is: Could I add a couple driving lights on, to the bike. They are 55watt which would be 4.6 amps roughly. I would only run these at speed, on a seperate switch than main lights. I plan on led's in the rear but not right now, I have the driving lights sitting here from past project.

pamcopete

bbjsw10,

Well, the headlight, tailight, ignition and rotor draw about 9.8 Amps @14.5 volts. If you use 14.5 volts for the driving lights, then they would draw 3.8 Amps each. This all adds up to 17.4 Amps. The alternator is rated at 16 Amps @5,000 RPM. 5,000 RPM is about 72 MPH on a standard bike.

So, the battery would slowly be run down because the alternator could not keep up with the load.

All of this is based on a new alternator from the factory. Real life expectations would be more like 14 Amps @ 5,000 RPM.

So, you could just switch the driving lights on when you need them using a relay connected to the hi beam circuit in addition to the on / off switch. That way you would not be distracted when you are riding down the highway at 72 MPH and an oncoming car flashes their lights at you.

LDO107

pamcopete wrote:

You will probably find that you do not have an alternator capacity problem if you change the brushes regulary and keep the rotor slip rings clean.

Pete,
what is used to clean the slip rings??

pamcopete

LDO107

1. Start by removing the brush holder to gain accesss to the rings.
2. Cut some 1" X 1/4" strips of emery cloth.
3. Start the engine.
4. Wrap the emery cloth strips around the end of an eraser of a regular pencil.
5. Hold the pencil eraser with the emery cloth on each slip ring with the engine running.

bbjsw10 · Full Member Joined: Jul 15, 2009 Posts: 64

Thanks Pete. Maybe I will try and figure out some other rotor/stator options. I have read the banshee rotor thread before, but looking at other options as well.

I figured my amps wrong I used 12v instead of 14.5v Thanks for the correction as well.

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