I am a new airhead owner doing my first tire change. The Po had a 130/90-18 which would rub inside the fender unless the shocks were set at 2 up. So I'm replacing with a 4.00-18. Had to remove front wheel and strap axle to the center stand, then deflate rear tire use c-clamps and wire ties to get the tire to fit between the brake and swingarm. I had two spacers fall off while I removed the rear axle and I only heard them hit the concrete and don't know where they were located. The parts diagrams and pics I've found don't show their location and may indicate they should be in the bearing stack contained in the hub?