I used the
Yakima Mount and ran a M8x1.25 bolt up through it. I used a
40mm coupling nut (which was way too long) Ended cutting about 17mm off of it. I used the top portion of the lock system along with the locking handle. I had to cut off about 20 - 30 mm of the bolt on the handle. (I don't know if they make a smaller lock system for a thinner tank. That would work better. They have several sizes)
I did this set up for the front and rear cross bar.
To lock it, you place the top cup
View attachment 2430572 into the opening of the Rototrax and line it up with the coupling nut. Then insert the locking handle and screw down. (that is the PITA part. You have to stand on the wheel to be able to look down into the top cup to line up the bolt hole and coupling nut) I am sure someone smarter than me could figure out a way to make it easier to line up.
The lock seems OK. It's pretty basic compared to the RotoPax lock. I think if someone really wanted them it could be defeated, but the good thing is that there are 2 they have to get through. For what little use they will probably get from me, it was worth the $80 plus savings. If I used them a lot, I would consider the RotoPax lock for ease of use.