Ok mate nice and simple this one
Your bushes have worn
Projump do a bush repair kit with all the bits you need in it
Not sure if you need one kit per stilt or what as I only saw the prototype kit so give them a shout
I tend to glue my bushes in as this makes them last longer also use a silicon lubricant on them to reduce wear
Have a look at the tutorial BitLord83 has done here
http://www.projumpforum.co.uk/index.php?topic=7280.0And the one for the older stilts by gillybert here
http://www.projumpforum.co.uk/index.php?topic=1271.0Before you order anything though take the bolt out of the top joint and have a look to see if they have worn just in case something else is causing it
A lot of people just keep using them when they are worn but I think they feel better when all the joints are nice and taught
Jason
Ps I resisted right up to here to make this joke
Steddy as a Rock,rock,rock
Sorry