I've been a bicyclist for years. When I bought my Toyota Tacoma, I needed a way to haul my bike. I wanted a rack that would hold the frame and wheel securely, but not take up too much bed space or interfere with cargo. There are several options that you can buy, but all of them had disadvantages. So I came up with this solution.
Step 1: Gather Supplies
My truck bed had a roll top. I didn't want to interfere with it or drill any holes in the bed. Each truck will be different, but I determined that the best solution for mine was to mount a 2x4 to the roll top box, close to the top, but far enough down not to interfere with the roll top. I bought the following:
2 - Yakima lockable fork mounts for the bikes
4 - 1/4-inch mounting bolts for fork mounts, 3/4-inch longer than thickness of fork mounts
2 - Delta wheel mounts.
2 - 4-inch hinges with removable pins
1 - metal rod slightly smaller than hinge pins
4 - 1/4-inch bolts 1/2 inch longer than thickness of wheel mounts
4 - 1/4-inch bolts 3/4 inch longer than thickness of wheel mounts
12 - 1/4-inch lock washers to fit bolts above.
12 - 1/4-inch nuts to fit bolts above.
3 1-in eye bolts
6 flat washers to fit eye bolts
3 lock washers to fit eye bolts
3 nuts to fit eye bolts
Step 2: Modify Hinges
The fork mounts needed to pivot up and down to accommodate different
wheel sizes and not get in the way when not in use. To accomplish this, I bought two 4-inch hinges from the local home improvement store. I also bought a metal rod slightly smaller than the hinge pin, and 4 bolts a half inch longer than the thickness of the fork mounts. Back at home, I removed the hinge pins with a punch. Next, I cut two pieces of metal rod about 2 inches longer than the width of the hinge and ground the ends smooth on the grinder. One end of each rod I bent to an L shape. On the other end of the rod I drilled a small hole just large enough for the cotter pin. I then test-fit the rods and cotter pins on the hinges. The rods should fit the hinges slightly loosely, and the cotter pins should insert and remove easily from the holes in the new hinge pins.
Step 3: Mount Hinge Halves & Drill Holes
One half of each hinge should be bolted to the wheel mounts, and the other half to the 2x4 mounting in the bed. In my case, this required me to drill holes in the hinge halves to match the mounting holes on the wheel mounts. In order to provide enough space between the bikes, I chose to put the wheel mounts between the fork mounts. First measure the bike and wheel width to ensure that there is enough clearance between the various mounts. Here are the measurements I used: fork mounts: centered 13 inches from center, wheel mounts: centered 4 1/4 inches from center. These measurements have proven to give sufficient clearance between all parts of the bikes. All holes on the 2x4 should be counter bored a 1/2 inch so that they don't extend beyond the back of the 2x4. The through hole should be big enough to allow the bolts to pass through, and the counter bore hole should be large enough to contain the flat washers. I also chose to mount 3 eye bolts on the rack to provide extra tiedown points for other cargo. This step is optional, but I've found these tiedowns very useful.
Step 4: Mount Rack in Truck Bed
Once all of the mounting hardware has been bolted into place, mount the 2x4 into the truck bed. For my truck, I screwed 2 short pieces of 2x4 to the sides of the roll top box, then screwed the mounting 2x4 to those with long wood screws. This meant that the mounting 2x4 needed to be cut to be 3 inches longer than the width of my roll top box.
Other mounting options are to have the rack insert into the stake pockets, or to build a frame that fits snugly into the space between the front of the bed and the wheel wells. You could also mount the rack backwards near the top edge of the tailgate.
Step 5: Test Fit
Next attach the wheel mounts to the hinges using the L-shaped hinge pins and cotter pins. Test mount the wheels and bikes. Turn the pedals all the way around to make sure that they don't hit anything else. If you've measured properly, this shouldn't happen, but if it does, go ahead and fix it now. You can leave the wheel mounts in place, but they can be easily removed using the cotter pins if they interfere with other cargo.