The fork is held in place by a silver washer and a gold lockwasher. If the t-bar seems loose in the fork or turns without the wheel the wedge must be tightened. Fold the handlebars and tap out the nylon plug. Align the wedge and tighten it with a 6mm allen wrench. If the fork seems loose in the frame, loosen the wedge and remove it.
Hand tighten the silver washer and tighten the gold washer with a wrench.
Do not lose any of the fork bearings. Properly oiling your chain will greatly extend life. If the small chain is loose it must be replaced. Remove this bolt and pry off the sprocket with a screwdriver. The large chain has chain adjusters on the rear axle.