Well, Motnik is right time, for an update.
We decided to drill the rotors because I loose a lot of braking power on my '82 when riding in the rain. Figured drilling the rotors can't hurt and might even help. I took my inspiration from Sgwilly in this thread
Drill, Baby, Drill!. However, I wanted more of a spiral pattern.
To accomplish a spiral pattern I started out like Sgwilly did by tracing the outline of my rotor and marking the bolt holes on a piece of paste board. Its important to mark the bolt holes particularly on the fronts because you want the spiral pattern to match up on both rotors.
I then determined the center of the circle by measuring the diameter and dividing it in half.
I then determined the center of the rotor by drawing several arcs with my compass from different points on the circle. I figured the law of averages would reveal the true center to me by doing this.
Then I drew a line through the center of one bolt hole and through the center of the rotor. This line will determine the starting point for my pattern.
Using a framing square I drew a perpendicular line.
After extending the line I measured four 10mm increments from the outside edge along the primary line and then drew concentric rings with my compass.
I divided each quarter by measuring the midpoint of where the lines crossed the arc then drawing a line through the midpoint and the center. Repeating this until I got the spacing for the holes that I wanted. Tighter spacing of the rings will allow you to drill smaller holes and still get overlap from one hole to the next.
I experimented some and figured out a pattern that came out evenly from start to finish.
Then it was just a matter of cutting my pattern out and taping it to the rotor, making sure to line up my primary line with the bolt hole that I wanted to use as a starting point. Since its easier to drill from the back side of the rotors you want to make sure your pattern is going the opposite direction from the way it will be seen from the other side. Make sure when drilling the other front rotor that your pattern is the mirror image of the first rotor. I used a spring loaded center punch to mark the rotor through the paste board. Worked quite well.
After making a pattern and marking all three rotors.....
it was off to Sgwilly's house to borrow the use of his drill press.
Here's Steve hard at work on one of my rotors.
Unfortunately, things didn't go all that well during the drilling process. After completing the first rotor Steve turned his drill press off and then we couldn't get it started again because the bearings seized. So Steve borrowed a press from his dad and later that afternoon we got the other front rotor drilled. When we started on the rear rotor we began eating up drill bits like there was no tomorrow. Never did get it completely finished. Either that rear is made from steel forged in space from a meteorite or the temper was changed from heat while on the bike. Either way Its now at a machine shop to see if they can finish the job we started. Funny thing is Steve drilled the rear from his '83 and from a '75 that he is restoring without any problems. Just my rear rotor is giving us fits. Go figure!
Here are the front rotors mounted on the powder coated wheel with a new tire balanced with Dyna Beads.
Well we've been working on more than just the rotors. I rebuilt the front forks. I purchased 2 inch over stock length fork tubes from
Forks by Frank. I got the link to his web site from Randaak's web site. Frank did a really nice job. I just told him what I wanted and he did the rest. Very quick manufacture and delivery. Very satisfied with his work. When I rebuilt the forks I replaced both bushings and substituted progressive springs for the stock springs. New seals and dust bushings along with new crush washers and the forks were ready to put on the bike.
This is pretty much how the bike is sitting right now.
We've begun rebuilding the calipers and the master cylinders. I still need to order some stainless brake lines to replace the 28 year old rubber lines.
. Disassembled, cleaned, replaced rusty hardware and mounted the ignition switch and gauges. I found that Home Depot is a good source for stainless metric acorn nuts. I replaced all the acorn nuts on the back of the meters after shining the chrome with SOS pads. Also cleaned and touched up the lettering on the handlebar switch assemblies and mounted them. This allowed me to install the grips and hook up and adjust the throttle and choke cables. The handlebar controls are up next for refurbishment. 
