Welcome to the new and improved Proflex / K2 Tech Forum!
One thing I have noted with my proflex 957 rebuild is the rear shock feels slightly loose where it attaches below the saddle. There is just slight play as you lift & drop the rear wheel, using the saddle as leverage. Is it something I should look to "pack out" somehow or is this how proflex designed it?There should be no play in the top bolt for the shock. I take it the pay is vertical, not hoziontal. Horizntal could be due to bolt coing slightly undone. Vertical means there is wear in the bolt, bush or shock eyelet. Most likeley and hopefully it is in the blt and bush - bolt is easiest to replace, bush not so. You need to take the bolt out and take a look As another thing, I have noted when applying high leverage on one pedal the whole frame at the bottom appears to move to the side slightly. I assume this is just the "flex" in proflex but would be good to confirm otherwise. I do have a slight bit of play in the crank/bottom bracket which I need to investigate, but is not affecting the bike - gave it a good kicking on Dartmoor (google it ) and it never felt too out of shape.It will be rear traingle flex - have had that with the chain rubbng on the front shfter. agian by "slightly" how much play are you talking about? Having play in the top shock mount is not doing you any favours.