Custom Roof Tire Carrier

Custom Roof Tire Carrier
For Aftermarket Round Bars

by Andreas Ritterbusch
Posted: June 19, 2001
Last Revision: June 29, 2001

First of all this project is not really intended to be reproduced, simply because I chose the most complicated way of doing this. Why? Because I am nuts, --most likely anyway! Now, the real reason was that this was a "warm-up" project to get back into fabbing stuff. I also recently acquired a small MIG welding machine and simply wanted to get some practice done on at least a semi-real project. Therefore, the following includes a lot of welding.
This project could have been realized much simpler. In fact, it could have been done with one cut and five holes drilled... The purpose of this tire carrier is to mount a 31" spare tire safely on the roof. I already have four Yakima round bars mounted to the factory roof rail (not rain gutter). This is a surprisingly strong construction, and the spare tire will sit on its own two round bars in the back and off to the passenger side. This allows me to load long items over the driver's side (this is the rig that acts as a lumber hauler from time to time!) A rear mounted tire was vetoed by the primary driver. Rear visibility is still good, the cargo area increased, and the rig is easily detected on a large supermarket parking lot.
	OK, here some of the first basic building blocks. Some channel iron, some flat iron (both end pieces are already cut, and one already drilled for two u-bolts). Also shown is one of the u-bolts (typical hardware store item). [Large image]
	Detail view of one of the end pieces. [Large image]
	Here the second end piece receives some final touches. [Large image]
	Both end pieces are ready to be welded to the center piece. All sharp cuts are deburred, and the corners are rounded off a bit.
	The end pieces are welded to the center piece (channel iron). The u-bolts are in place to show the position of the roof rack cross bars (this is a side view). [Large image]
	At this point, I decided to add a bit of class to this... i.e. add some stuff that is not really needed! A: this is a bracket for 2"x4"s, but I thought it would add a nice touch to this roof carrier (plus, it allowed me to re-use the original (metric) J-bolt (B). B: this is the modified J-bolt (see image below). C: the flat metal will prevent the modified J-bolt from spinning once it's up in the short piece of channel iron that I had previously welded underneath the 2"x4" bracket (A). [Large image]

	This is the modified J-bolt that usually holds the stock spare tire in place. I cut off the end and welded on a piece of 1" wide flat iron that will fit perfectly into the channel iron and therefore will prevent spinning when the tire is to be tightened down using all the original hardware (semi-globe, plastic wing nut, etc.)
	This image shows the the tire on the roof in the background and the new tire unfinished tire carrier in the foreground. This is roughly the final position of it. The 31" spare tire has its own two dedicated Yakima round bars and will not go anywhere! The image also shows the original mounting parts usually used in the interior. [Large image]
	Close-up. [Large image]
	All painted and ready for the big tire! Since the u-bolts from the hardware store were a bit larger than the Yakima cross bars diameter, I used a bit of clear plastic hose to match the u-bolts' diameter. The were tough to get on (even with soap&water on a hot day). [Large image]
	Looking under the now mounted tire. [Large image]
	Looking from above into the tire. Note the OEM semi-sphere and wing nut to hold the tire down (same parts that are used to hold the tire inside). Since the wheel is facing downwards, some stuff can be put in here on long trips (I added a tire cover). [Large image]
	Tire mounted on the roof. (I put a tire cover over it. Not shown in this picture, see image below). The tire is not centered on puropose. The left side of the cross bars is "open" in order to load up long pieces of metal or lumber.
	View from front. The tire and the Yakima basket are mounted over the passenger side, leaving clear the full lenght of the roof over the driver's side (about one third of the width of the roof).
Summary: Awesome mod! Total overkill, but fun! The tire is easy to mount, which is relative, considering that it must be lifted up there! Further, a roof-mounted tire also adds to the the drag (wind resistance) and therefore decreases the mileage. Advantages: -Increased cargo room. -Rear view not impacted (as is the case with a bumper mounted tire carrier). -Rear lift gate easily accessible (no swinging away a heavy tire first). -Tail lights not blocked (depends on swing-away tire carrier design&approach angle). Disadvantages: -Tire must be lifted onto the roof, which requires physical strength. -Tire on the rood adds to the drag and reduces mileage. A faring might help.
ŠCopyright 2001 Andreas Ritterbusch All Rights reserved. Photos: Andreas Ritterbusch

[MADXJ]