aacoop,
I went back and looked, cause I also was thinking that was a bit of a variation too.
It really should be 19mm each side. here's where I screwed up:
I use a laser pointer that I fabricated into a really great way to line up sprockets. I simply epoxied two small magnets to it, and leveled it out on a piece of 3/8" glass so that it dried level.
What i forgot to to was deduct the depth of the pointer from the numbers for alignment, so I was exactly 5.5mm off. so-if you deduct 5.5 from the 24.5 and add it to the 13.5, they are both 19mm.
hope that makes sense, I think all i need to get the laser to work really well is to add a 5.5mm magnet surface that sticks to the drive sprocket and it will be real quick to align the sprockets, and about as dead on as you could possibly get..
k
