Yeah, unfortunately mine has the ignition points too...But the good news is that Honda still sells them...$25...
Yours and my bike are totally different....Mines an XL100....(I guess I should have said that earlier)
For mine (XL/XR100) Basically the engines (cylinder, head, carbs, cases) are the same from 1982 through today! the only change took effect in 1994 when then changed over to CDI ignition...but that's it...
My bike sat outside in my parents yard since 1989...until about 3 weeks ago (16 years!) The speedo say's 3300 miles...and I know it's true...and it did work the last time I rode it!
Mice are wacky...I had a nest in the airbox, and the headlight....The headlight also housed alot of the wiring...Thankfully, they only ate the wires feeding the actual headlamp...Everything else was intact.
I tore the whole bike down...Bascilly the frame, engine, electrical system, some controls, blinkers and tailight were all that was good...EVERYTHING else was rusted solid (gas tank had a bunch of holes through it, wheels, hubs, brakes, Cables, Carb)...So I went out and bought a complete donor bike...
The carb was filled solid with a white substance...I have never seen one so badly caked up...It's worthless...The oustide looked fine...
So you ask where to start...Well here's what I would do..
1) Take the plugs out, and spray a ton of WD-40 in each of your cylinders...let it sit overnight (while you have the WD out, spray every nut and bolt you can find...
2) Take tank off, put alittle gas in it, squish it around, then empty it...
3) Get a tiny inline gas filter and place it in the fuel line
4) try to torn the bike over gently by hand WITHOUT the plug in it. If you feel any resistance, then you might have a sticky valve, warranting you to take the head off for inspection...
5) If it turn over easily, then put a plug in, and try to start her up...
If your lucky, then you should be able to take it for a ride....
Remember, it's a HONDA, so I wouldn't be surprised if it starts right up and is ready to go!!
Take some pics...and share them with us....
Here's some of mine (There's one of how it looked when it was new, current, and some of how it will look when it's done!):
http://groups.msn.com/ATVNJ/xlxr100restoration.msnw