I have a 2006 Trek 5200 with the Bontrager Race Lite wheels. I upgraded
the componentry to Campy Record, and Trek exchanged the wheels fro
Shimano to Campy compatible at no cost. The wheels are 20 spokes front,
24 rear, and the rear is laced two cross on the drive side, radially on
the non-drive side.
I now have about 8500 km (5300 miles) on the bike. Recently, I noticed
that the rear wheel was a bit out of true. I checked, and one spoke on
the non-drive side was quite loose. I tightened it up to something like
the tension of the other spokes, and rode it some more. The next time I
cleaned the bike, the spoke was loose again. I tightened it again.
When I cleaned the bike on Friday, the spoke was loose again, and again
I tightened it. I rode the bike 67 km on Saturday, and today I checked
the spoke - it seemed a little less tight than the neighboring spokes.
What causes this to happen? Do I need to take it to the shop? The bike
is one year old later this month, by the way.