There's a few wheel alignment tools talked about here:
I just use two threaded rods one in the axle one in the swing arm pivot. It's not because I think the Gillis chain adjusters are inaccurate, it's just easier to do standing up. I can easily get to within less than one MM using a standard tape measure. it'd not my idea I just wasn't willing to...
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I don't think any one of them can guarantee perfect alignment but it's a way to check. The laser is the most direct way to do it so I'd think that most reliable. If you take the sprocket cover off to view the laser dot on the frontmost roller up close and compare to the rearmost roller the laser touches, I'd think you'd get as close as one can get. I'd prefer that laser beam be very narrow for acuracy but I don't know if it is.
I have had very good luck by doing the following:
1) Loosen axle nut.
2) Loosen adjuster bolts and draw locknuts up to bolt head.
3) Tighten adjuster bolts with locknuts drawn up to head all the way in forward. Max loose adjustment on both sides, both sides are exactly at the "zero mark."
4) Use a Sharpie or paint to mark one flat on each adjuster bolt. Use this mark on both sides to count the number of turns you put on both adjuster bolts so that the adjuster bolts both extend the same distance.
5) Bump the axle forward so the adjuster blocks are tight to the adjuster bolts.
The final adjustment, you will count how many flats you turn. As long as the same number of flats are turned counterclockwise, the bolts will be extended the same length and the sprockets will be aligned. If you need to loosen, again count one flat at a time and do the same on both sides.
6) Tighten adjuster bolt locknuts. Tighten axle with axle nut on the RH side lifting the wrench handle forward to press axle adjuster blocks against adjuster bolts.
7) Check chain slack.
When you adjust the chain in the future, one flat on each side will be plenty. You might even go only a half a flat to achieve proper chain slack. You can rely on this method when the adjusters are between increment marks. Just make sure you turn the adjuster bolt the EXACT same amount on both sides. As you approach the swing arm mark after many adjustments, you'll see that both adjuster blocks are even. Use a Sharpie to mark the flat every time you adjust the chain.
It worked on my ZX-14. Wear on both sides of the sprocket was almost perfectly even. This takes a lot of careful work initially but if you get it right, it works. If you lose count on one side, you just have to start over. I don't see why a digital calipers couldn't be used to check equal adjuster bolt length on both sides. I'm hands on so I did it the caveman way.
Some people claim the swingarm marks do not correspond to perfect axle alignment. Seems to have worked for me and does seem to correspond to the adjuster bolts being turned the same number of rotations on both sides. I'd still like a tool to check these against...just to complicate the whole matter, so I need to second guess myself!
