alternator capacity

[tx07400ex]

Ok so im thinking of adding some stuff to my 400 that will draw a little more juice but im not sure if the charge system can handle the extra power consumption.

[puTTs]

147 Watts at 5000rpm in the owners manual. That's 37 Watts at 2500rpm and 9 watts at 1250rpm. I would try to keep any constant amp load under 10amps to keep from toasting the stator wires that looks about 12ga.

[tx07400ex]

yeah well if i put it on it will be direct wired to the battery, as long as the alternator can keep it up ill be ok im not sure exactly what kind of amps it will be drawing probably less than 30 at max output, its going to be a 200w 2 channel amp(a cheap one) btw, i just dont want to overload the alternator capacity.

[puTTs]

A 200 watt cheap amp probably has a efficiency of about 75% so it would take about 267 watts in to make 200 watts out. Assuming you have a good signal coming in and you have the right ohm speaker/s to properly load the amp. So 267 watts / 12 volt = about 22 amps if things are set up right and you have the amp turned to the max. Hope that helps, I'm still kinda clueless on the reason of why?

[tx07400ex]

main reason is 90% of my riding is with utilities, there are a couple of us that run sports but not many, the utes have stereos and they usually dont play anything i want to listen to, my buddy builds custom speaker boxes as a hobby and told me he could hook me up cheap so why not, i already have a custom rack on the grab bar to bring a cooler with me, but lately one of my buddies hauls the cooler on his 4x4, the whole thing will be removable for when i want to really go play the rack i can take off in under 5 min.

[sc400ex_rider]

an amp would be a waste just get a radio/cd player LOL thats puts out like 40w per channel. 40w x 4 channels = LOUD unless your trying to kick base or something.

[richards]

I agree, why bother with a cheap amp, just get a mid range head unit an use the internal amp.

But if you go with the amp, and it is a cheap one, it likely never will put out 200w while listening to music. The cheap ones are usually rated at 5 or 10% total harmonic distortion which will sound terrible and blow your speakers so you will likely never approach that level. So cheap 200w amp with a couple of speakers and I bet you draw 5 amps listening to music. Maybe 10 if you have it really loud.

[sc400ex_rider]

to find amps from watts divide your watts by voltage. 50 watts ÷ 12 volts = 4.17 amps

to find watts multiply your voltage by amperage = wattage. 12 volts X 10 amps = 120 watts.

the stock stator is only good for 8-9 amps. i think they make a high output stator for the ex. you can also use a busa battery they have 55 more amps but are the same size.

just get a radio with a 5 or 10 amp fuse and 4 speaker outputs. the headlights and ignition need some amperage too. not to mention the charging of the battery.

[tx07400ex]

i thought about the stereo idea but the whole thing is going to be behind me so im gonna use an amp and ipod to control it, i know cheap amps suck i have built quite a few systems i just dont want to spend a whole lot on it. and the iginition/lights were my main concern i didnt know if the alternator could handle running the neccesary things for it to operate and still have the power to run a system, most all of my riding is at night so the lights will usually be in use at the same time, i dont want to have to upgrade any of the electrical system if it wont pull it ill just do without a stereo

[puTTs]

If your running lights at the same time you don't have any spare power. You'd be better off with the boom box idea. I think the head lights are 30 watts each so X2 = 60 watts / 12 volts = 5
Amps. The ignition doesn't take anything to run, maybe .5 amps. These bikes weren't designed to run anything else but them selves.

[uchi]

not to thread jack, but would i be able to run a set of fog lights with my headlights on? i have a set sitting here but havent got anythign to put them on and rather than getting into a retrofit of any kind id just prefer to add lights for some night riding.

[sc400ex_rider]

how many watts are the bulbs? i dont think your going to have enough capacity unless you get some LED lights.

[richards]

Well as puTTs mentioned above you have 147W at 5000 RPM according to the Honda specs.

Headlight is 30W low, 60W high
Tail light is 5W
Ignition is probably not significant.

No sure what your fogs draw - I would guess something more than 55W each.

So that's going to be iffy at RPMs lower than 5000.

puTTs how did you get the numbers for lower RPMs? I do not see them in the manual, and thought it would be linear like 73.5W at 2500 RPM, etc. The numbers you gave above show it dropping of in a nonlinear fashion.

[uchi]

I'm having a hard time tracking them down. I moved a month ago and can't seem to recall where I stashed them. But I'm sure they're 55w. So I guess I'm better off running a higher wattage bulb. Maybe even those piaas. Will the stock wiring support a brighter bulb?

[puTTs]

Originally posted by richards
Well as puTTs mentioned above you have 147W at 5000 RPM according to the Honda specs.

Headlight is 30W low, 60W high
Tail light is 5W
Ignition is probably not significant.

No sure what your fogs draw - I would guess something more than 55W each.

So that's going to be iffy at RPMs lower than 5000.

puTTs how did you get the numbers for lower RPMs? I do not see them in the manual, and thought it would be linear like 73.5W at 2500 RPM, etc. The numbers you gave above show it dropping of in a nonlinear fashion.

When using permanant magnet alternators every time you double the rpm you quadruple the output. Same as if you cut the rpms in half you cut the out put to a quarter. I don't understand exactly why this happens. It has something to do with eddy currents building in the coils which actually makes the electons flow. I've built a few wind turbines for off grid home use. I have a little first hand experiance of how alternators work.:D

[uchi]

theyre 55 watts a piece, im thinking of running one, here are the pics i posted in another thread.


bottom of the bumper
http://img.photobucket.com/albums/v96/turbocav/atv/DSCN3154.jpg

top, not sure which i like more

http://img.photobucket.com/albums/v96/turbocav/atv/DSCN3155.jpg

in the middle

http://img.photobucket.com/albums/v96/turbocav/atv/DSCN3160.jpg

figure if i can only run one i might go this way, its pretty bright and between this and the bikes lights i should have plenty of light

and inside the workshop, again using only 1 light and its pitch black in there, pics were taken with no flash.

http://img.photobucket.com/albums/v96/turbocav/atv/DSCN3156.jpg

http://img.photobucket.com/albums/v96/turbocav/atv/DSCN3157.jpg

http://img.photobucket.com/albums/v96/turbocav/atv/DSCN3158.jpg