Markings on 350 rotor / different ways to set ignition timing…

Mikepacific60

Mikepacific60

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Hi all,
A couple of questions:
See the photo of the rotor below (which I pinched from another thread on this forum):

2B6803BC-AAB6-430F-BD20-1333FEB3E8AA.jpeg

Okay, so let’s focus on the Left side markings on the rotor, starting at LT (near the top of the photo) and moving anticlockwise…
Pretty clear that the “LT” represents the left piston at top-dead-centre;
“LF” is the mark used for static setting of the the ignition (test light goes off just as the rotor touches LF on the left cylinder compression stroke);
Now it gets a bit more tricky - I think the next two (unlabelled) marks are related to setting the ignition using a timing light. Specifically, as the engine RPM increase, the mechanical timing advancer behind the points advances the ignition to get the best possible performance from the engine.

If that is correct, can anybody fill me in on the details…..at what RPM should the timing strobe light align with which of these two unlabelled marks??
Thanks
Mike
 
I just searched the CB/CL350 manual with SL supplement for the spec and couldn't find it, but it was the SL350K0 supplement and since the camshaft changed in the K1 and K2 the spec is probably a little different anyway. It should be in the FSM for the K1. The CB/CL manual showed the advance curve beginning at 1800-2100 rpm but that was to mention when it began and not the rpm range of full advance. I'm guessing it's in the area of 3500 to 4000
 
Exact RPM is not the idea...You won't be able to hold exactly a numerically specific rpm anyway, it will vary slightly ( and appear to "bounce" between the two lines a bit)....
IF you are set at the LF line for the static timing, as long as the index pointer shows/gets to somewhere between the "paired" lines and remains within there once you do get revs high enough to be at full advance, and advances no further as revs continue to increase, you are fine.....
IF it doesn't quite get that far, you are running retarded, and if it goes past the furthest (anticlockwise) line of the pair, you are too advanced.......
 
I see in the CB/CL 250/350 FSM with supplement for the SL350 that full advance for the CB/CLs is between 27 and 33 degrees. It states that advance should begin between 1600 and 2000 rpm, reaching full advance been 3200 and 3800 rpm. There is no additional info in the SL section that I can find.
 
stl360+450 said:
I see in the CB/CL 250/350 FSM with supplement for the SL350 that full advance for the CB/CLs is between 27 and 33 degrees. It states that advance should begin between 1600 and 2000 rpm, reaching full advance been 3200 and 3800 rpm. There is no additional info in the SL section that I can find.
Click to expand...

Thanks for digging it up Brody (y)
 
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