Originally Posted by Ed Blown Vert
I was running 25* on my 150 shot. It all depends if you have KR.
I run 22-23* with my 175 shot and am still getting some KR in the summer heat even with 94 octane. Might try a slightly colder plug and see if that helps.
For a 125 shot, I would run 25-26* of timing, but you should still be safe with whatever your stock timing is set to. Running lean is usually a bigger concern.