84 XT, how many watts of power are available?
 

since I'm contemplating some upgrades for my XT, such as an HID spotlight for the bars to aid my night riding, I need to consider how much power the stock charging system generates.

I know I'll free up a considerable amount of power by converting the headlight to HID, and only having about a 30w draw off that, plus doing an LED tail light bulb, which should help as well.

but with a standard tail light bulb, and regular H4 halogen headlight, how much is available to work with?

The 1990 has around 180W as I recall.

If you free up some by using HID headlight aswell, i should see no problem.

2x30W hid + led taillight vs 55/60W headlight + 5W original taillight.

The math almost goes up. You cann free up some more by using led's for the neutral light, long lights and the instrument lights. Each should save 2-3W although they arent all uset the whole time.

I wouldn'y worry.

doesnt COMPLETELY help, but at least your info gives me a ballpark figure. I'm going on the figure of 100w since I have a kicker only motor with that TINY battery.

I'm figuring on the idea of just use one low draw HID light I can aim so I've got auxillary lighting for night riding on the trails, running an on off switch. likely it'll find its way to right about where the right mirror should mount.

Early stator output. Motobatt batteries.
 

Hi Bob.
Many years ago, when I used to fit early stators, like yours (34L/43F/2KF 4-bolt 2-wire type) to Japanese built, 6v TT600s, I could never quite get enough output to run two 55/60w halogen headlamp bulbs. (I used to have 2 x Cibie Hi/Lo lamps on my supermoto TT600)
They'd work ok at startup, but once the engine & stator were warm the lamps were dim, even on low beam (110 watts)
So I came to the conclusion that the true, hot output was greatly less than 100W.
The battery size doesn't matter really unless you need high current draw for electric start.
So...if you use a single Bi-Xenon (Hi/Lo) H.I.D lamp drawing 30-40w, you should be fine.
And make sure your regulator/rectifier is working ok. (13.8v-14.2v at the battery at 2000rpm with a fresh, fully charged battery)
Motobatt do an incedible, AGM sealed battery that will fit inside the old, early YB5LB battery box. They have a much larger capacity than a 'wet' YB5LB & won't spill acid everywhere if you fall off.
Just out of interest & curiosity, I started my car with one of these!

David Lambeth.

Hi David, and thank you for the information. I initially figured the actual output was around the 100W area.

when I brought the bike home, I did do a test and verified that I was seeing 13+V at 2000rpm. I thought this a bit weird, but I dont mind since it does the task.