I just tried a black fluted post in my Mongoose frame. No dice. Tried in in another frame. No dice. Tried another post in both frames...smooth as silk. Looked closely at the black post, and it's stamped 22.6. I've never seen such a thing. Has anyone else?

Bill,
Some Redlines used the 22.6 posts, mostly mid
80's!

hey bill;
i can confirm what ben has said. i have a fluted cro-moly redline post that is 22.6 mm in diameter and measures 14" long (i guess saddle heights were creeping upwards in the mid 80's or something) as opposed to the original version's 11".
dave

Cool. Thanks guys.

My 85 or 86 CW Z-1500 has a 22.6 as well. Had to shim the hell out of my 22.2mm Renthal laid back post...