Over the last few years, a big change was made in Mountain Bike fork designs with the 15mm through-hole axle. While this gives a lot more stability for downhill racing and for larger (heavier) riders, it has also proven to be a bit more of a hassle to transport your bike from place to place.
There are conversion kits you can buy from Thule and Yakima, but they are upwards of $40 and clip on to an existing rack system. If you want to mount to a truck bed or SUV floor, then you need to buy two components, totaling ~$80. I went to two local bike shops and a specialty rack shop and no one had what I was looking for so I decided to make a quick stop by the local hardware store and design this on the fly.
Step 1: Parts List
The real magic of this is that the inside diameter of a 1/2" pipe is large enough to have the 15mm axle inserted into it. Most of these pipes have a smooth enough inside surface but I did end up sanding the inside of the pipe a bit so it would not scratch my axle. An alternate design would be to use 1/2" PVC pipe and then have that in a slightly larger galvanized pipe with basically the same deign. That would made since the axle never gets hurt since the PVC is a softer material. I realized this after I did this project but it is really your choice.
My Parts List:
(1) 1/2" diameter, Galvanized pipe "T"
(1) Base / pedestal floor mount
(2) 1/2" diameter Galvanized pipe, 1" in length (you the actual length depends on how tight you wrench it together and how much slop you want.
(1) 1/2" diameter, 2" length (this can vary a few inches depending how high you want it to be, keep it lower for less stress on the part.
(1) Base wood stand (I had a piece of 3/4 plywood (4" wide x 34" long) around so I used that. You could use a 2"x6" if you want. I would keep it at least 36 wide so stays flat on the SUV or truck floor.
(4) 3/4" wood screws
(1) Paint (optional)
(1) Fabric (optional, but it sure makes it look nice)
(1) length of 4" wide, 36" long male Velcro
(1) Spray adhesive (optional, used if you decide to cover the base with fabric)
Step 2: Assembly
This is the easy part, but make sure your parts are as tight as they can be as there is a lot of force on this and you don't want to loosen up over time. If you have two plumber pipe wrenches, then use them to hold one while you tighten the other. Make sure to line up the mounting holes which connect to the base in an area where you can get to the screw openings.
After I was done, I used some sandpaper to smooth all of the sharp edges off and make it ready for paint. I happen to have some black textured paint around. I always keep the textured style around as it hides a lot of evil when doing projects like this and gives it a finished look.
Step 3: Create the Base, Then Attach It All Together
Your design may vary but the main things to consider are:
Surface - What surface you are mounting to (SUV carpeted floor or truck bed)
Stability - Bikes tend to move a lot so make sure it is tight and if you do a temp mount like I did, make sure the wood is wide enough so it does not topple over or move around when you drive those twisty roads to you favorite mountain bike destination.
Longevity - Temporary or permanent mount (I chose to mount to a removable piece of wood)
For me, I wanted to have it in the back of my SUV and wanted to have it look very finished. I spent an extra 20 minutes (that is all it takes to make something to be proud of...) and routed a 1/4 round bevel on the wood, sanded the base, sprayed it with 3M adhesive and then covered it in some old fabric I had from another project. I stapled the fabric onto the wood and viola, done. If you have a carpeted floor, then that is where I would add the male Velcro to the underside so it sticks to the carpet.
Done. ~1 hour, <$10.
Step 4: That's It. Done!
It mounts inside the SUV and is pretty stable.
An alternate design would be to have the board wider and have multiple bike mounts added to it, but this is all I needed.
Enjoy and Happy riding!