P11 static ignition timing, getting it close

Schwany

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This is for those that want to get static ignition timing close and don't want deal with the mess associated with pulling their P11 primary cover off and putting a degree wheel on the end of the crank when changing their ignition. Same applies to taking the timing cover off and doing something similar. It is nothing new by any stretch of the imagination, but it is simple to do and repeatable for initial static ignition timing.

Use or make one of these.
P11 static ignition timing, getting it close


The tool serves two purposes. Finding TDC and in this case finding 29 degrees BTDC for a TriSpark ignition. To find TDC you'll need good eyes to spot where the piston is in the middle of the transition point of TDC. Get the piston close to TDC close before installing the tool. You could also use a piston stop to locate TDC, then remove it and install the above type tool. Once TDC is located scribe a mark on the rod at that location. I scribed it then took the rod out and used a very small file to score the rod. While the rod is out put another mark above the TDC mark at .3545" That will be 29 degrees BTDC, or very close to it*. Drop the rod back into the rod holder and back the crank up until the top mark is lined up with the top of the timing tool.

*Obviously, there is a gotcha or two and that is the diameter of the rod and the radius at the bottom of the rod will affect the distance between the marks. The rod diameter for the old timing tool used in this example is .312". I'm not sure of the radius unfortunately. In addition, you should never have the rod in the rod holder unless you are positive the cylinder you are checking is close to being at TDC on the compression stroke with both valves closed. Also don't bring the crank all the way around again with the rod in the holder. You'll end up wedging the rod against a valve possibly bending a valve, or putting a nasty ding in it.

I used a degree wheel on the crank and marked the tool. 100% repeatable on "my motor" on either cylinder as it should be. I no longer use a degree wheel to find 29 degrees BTDC. Most Nortons that can't be easily strobed should run well enough at 29 degrees static BTDC. The P11 Red book says .343" for 32 degrees BTDC. 32 degrees BTDC is the standard ignition timing for a stock P11. I did not verify what that number works out to be for the tool I used, but it sounds about right if measuring straight down from TDC, and not with the tool at an angle.
 
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