purerockyfury71,
A. The end play on a stock points advance setup is .5mm. The end play for a MikesXS advance rod is 1mm. The stock end play is OK and should not produce a noticeable timing jitter. The end play on Mikes advance rod might show some jitter if you look closely. You could install a .5mm washer type shim in the MikesXS setup, but I would not advise shimming the stock rod as some end play is needed for thermal expansion of the rod.
B. If you are going to install a .5mm shim in a MikesXS rod, then install it on the advance side.
C. In both cases, the amount of timing jitter will not affect the operation of the engine.
D. Ensure that the PAMCO rotor is fully seated on the end of the advance rod. The best way to check for this is to remove the rod and do a test fit. Do the same for the advance slotted disk.
1. You should also adjust your timing chain tension. A loose timing chain will cause timing jitter, as will a worn out timing chain.
2. Check the tension on the return springs. The advance should return so the advance weight arms are up against the slotted disk.
Notice that you can see some tension in the springs (spaces between coils)
3. You must have either resistor caps or resistor plugs for proper operation of the timing light.
4. The idle must be steady.
5. Engine must be warmed up.
6. Excessive idle speed (>1200 RPM) will cause the advance weights to be right at the point where they start to advance, causing timing "jitter", so perhaps a little work on the carbs for a steady idle at 1200 RPM will help.
7. Here is a video of the correct "snap back" action of the advance.
You must have this crisp snap back action for proper timing.
Thanks 5twins and RG for your help. I installed this review in the web site as the quesiton does come up from time to time.
