Not sure if you are aware of this or not but the “octalink” axle spline pattern is not symmetrical all the way around. There is one spline that is thinner (or maybe thicker, I would have to go look). This is important because it references the drive and non-drive arms at 180 degrees from one another. The incorrect spline engagement looks a lot like the correct spline engagement which makes for a strong possibility that incorrect installation could go ubdetected. Tightening down a crank arm that is out of position is possible but because it is not fully seated on the splines tab, it can shift later while under load.

Now i I have not worked with the track Octalink but I believe it should be the same concept as the road Octalink. The one I have is the Ultegra 6503 triple.

Now I cannot say for sure if what happened to me happened to you but it sure sounds like it. The way I positively resolved my issue and restored full confidence in the strength and reliability of the system is as follows: 1) make sure the interior threads of the hollow axle are lightly greased 2) do not use a standard 8mm Allen wrench, it is one sided and has the problem of not providing enough tactile feedback and does not apply tightening torque evenly. Instead I highly recommend a sliding “T” bar that takes an 8mm Allen bit. I like 3/8 drive since it is a bit stronger than 1/4 but leads massive than the 1/2 square drive Allen socket. So long as you have you auto extract bolt fully tightened into your crank arm you can then line up the mating splines, taking care that it is on the correct axle locating pin. Start tightening the T-bar with the 8mm bit and you should be able to feel if there is any resistance. If there is you can always back it out, check everything and try again. Once you are locked on where you need to be, you’ll feel that the splines are snuggling up properly. The greased axle threads help with this feel. Applying equal hand pressure on both ends of the T bar, tighten the auto extracting bolt quite tight and it will stop at some point when it is very tight so don’t force it beyond that point.

when done this way, you will know without question that it is installed correctly. I feel that the Octalink USA very elegant, strong setup that gets bad press at times for what is really a mechanic issue. Loctite is not necessary or appropriate here in my opinion.

if it would make you feel better, you could also use crank bolts of the correct size and forget about the auto extractor bolts. Some of the XTR Octalink cranks connected this way Ithink.

As for whether a slight asymmetric projection of the auto extract collar is a problem - I would say don’t worry about it so long as the threaded collar that holds the crank bolt is not cross threaded.

I’m curious to know if my advice is helpful or applies to your situation at all.