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Hi All, With being mostly house bound with virus rules, I've had a chance to mess around in the garage. I decided to make a degree wheel set up for cam shaft to do strobe timing on early bikes. Really just because I wanted to. It worked quite well. The light reading was same stable as on alternator rotor on later bikes.

Not suggesting you do this, but I wanted a better way than I'd been using & I have lots of free time right now. Weather was rainy too.

Finding TDC with piston stop proved problematic with Wassell degree wheel. The degree wheel doesn't really have enough marking circumference to properly use piston stop to zero wheel. The full 360deg circle wheel worked as expected. I've not used the Wassell wheel before. With the Wassell wheel you must locate TDC or 38B with TDC tool or some other method. I was hoping to use this degree wheel, but I couldn't get reliable results. Normally I like to zero wheel with piston stop at 30deg crank shaft. When using TDC tool I did crank rotation in normal forward direction to eliminate backlash in gears.

My Wassell kit came with CEI spindle. So I made a spindle from 1/4-28 threaded rod. The aluminum adaptor is threaded down center so it tightens against AAU or with spacer washers Boyer rotor. I also made a cupped washer so AAU can be held at full advance for static timing should unified thread cam be used in early motor.

I've always used pointer made of wire mounted under screw on timing cover. Any time you remove screw it's a risk. Oil leaks or thread damaged. Plus the wire is wobbly, especially with motor running. Since I had free material 3/16 aluminum plate on hand I wanted to see if I could do better, yet simple to use. So I cut out the plate, bent it, mounted a wire. I flattened the end of wire as Wassell degree wheel is marked crankshaft degrees, so lines are close together. Each line is 2 degrees. The plate mounts to pillar bolts, which of course have a small hex head, but it proved very stable. Bolt holes are elongated to allow for tolerance of pillar bolt position. We'll see if it needs elongagtion more as time goes along.

Even though the Wassell wheel is flimsy & floppy, once it starts to spin up it is very stable. Be mindful to tighten spindle well so things don't slip when running. A good plan to verify TDC after adjustment to be sure.
Starting motor & reving to 4000 the timing light read good & I could easily see timing marks & pointer to exact. The stiffness of pointer plate allowed no vibration whatsoever.

TDC stop proved not so simple. The intake valve hit center stop bolt. So I ground down bolt to 1/4" dia to give clearance. Be sure to very carefully check for clearance to valves should you use piston stop.

Piston stop is simply spark plug where I hack sawed the crimp around porcelain through & knocked out porcelain. Grind or file end smooth. Cut off & smooth ground electrode. Tap drilled for 3/8-24 & threaded to hole. Found 3/8-24 bolt in my drawer with longest threads. You see a slot cut in side, that's to let the compression air out. The factory made stops often have vent hole drilled down center. My bolt happened to be hard metal so I slotted it.

For owners of early machines that want to install Boyer or the like that MUST be strobed timed, it may be better to get a chepo later cover that has timing window & pointer. No matter if it's cracked or dented so long as pointer location is still intact. Be aware T140 cover pointer is much shorter so will be farther away. So 650 cover is what I'd recommend.

But if you have a degree wheel & can zero it. The degree wheel works good with strobe light. Again, verify it didn't slip after strobe timing.
Don
 

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