Originally Posted by gkull

The lash is set by the nut. So with the allen lose rotate your box end wrench to the point of correct lash. Then back off the box end wrench 1/8th or what ever it takes. Then tighten your allen down snug and tighten the box end that 1/8th or so to the previous correct lash point.

That loads the allen tighter than you could possibly do with an allen wrench. I've never had mine come loose even on race motors