THIS CAN BE USED ON EARLIER BIKES THAT USED THE 4CA AAU AND POINTS PLATE WITH THE CONDENSER ON IT. ONE JUST NEEDS TO SWAP OUT THE POINTS PLATE WITH A 6CA TYPE. THIS WILL ENABLE MUCH EASIER ADJUSTMENTS AND WILL ALSO ALLOW THE CONDENSER TO BE MOUNTED IN A REMOTE LOCATION OUT OF THE POINTS CAVITY. MUCH EASIER TO REPLACE THE CONDENSER IF IT IS A REMOTE LOCATION. USE LATER CONDENSER 54441582
This cam can be used in place of 54419653 15 degrees
Given that the timing is set at the full advance position the engine would run fine at the top end.
Some unit single enthusiasts feel the 12 degree AAU is an improvement over the 15 degree AAU. This is specially true if you time 28 degrees full advance BTDC as suggested for the earlier Victors, as the 15 degree cam actually retards to 2 degrees past TDC. You may have to slow down the idle on the carb but it certainly won't harm and may even accelerate better.
If you want to increase the retard to 15 degrees:
Measure how far the pin travels in the limiting slot (leading edge of the pin to where it stops at full advance) and multiply that amount by 1.25 to get the total travel of the pin you need to go from 12 to 15 degrees.A 12 degree AAU has about 0.134 inches movement for 12 degrees. Therefore you need to go to a total of 0.167 (add 0.033) for the pin movement to get 15 degrees. A Dremel tool with a burr should do the job.
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