If you haven't read the post how we mount the motorcycle fender on the hardtail frame, check it before continue reading. Now that the fender is securely mounted at the top and bottom hardtail frame cross-members, we need to fabricate some fender struts or a sissy bar that will hold up the rear of the custom fender. To do this I chose some 1/2" diameter cold rolled round stock. I also used some full radius 3/8"-16 threaded bungs and some counterbore bungs that accept a 3/8" allen head bolt, keeping the head flush mounted for a clean look. We have a DIY Fender Strut Kit available containing all of this as well as stainless steel hardware.
It is easier to mount your bungs to your motorcycle rear fender and frame and bend the steel rod to fit, so I went ahead and drilled some 3/8" holes in my fender and bolted the full radius bungs to it.
Next I lined up the counterbore bungs on my axle plates and scribed the hole where I needed to drill. My 3/8" thick axle plates were beefy enough to drill and tap, if you wanted to mount your struts differently you could also weld a threaded bung onto your frame or a tab that could be bolted to the lower end of your strut. I then tapped the hole with 3/8"-16 threads.
Now that I had my upper and lower mounts all bolted in place I cut a piece of the 1/2" steel rod several inches longer than necessary and used our state-of-the-art bender to get a nice curve so the strut would meet the top fender bung nicely.
After getting a nice bend to it, I cut the strut to the proper length and filed it to be a nice tight fit before tacking it in place and then doing the finish welding.
The finished struts turned out great and took less than a couple of hours from start to finish. Nice and sturdy, they are able to support a passenger on the fender with no problem. The biggest thing with a project like this is taking your time, the second strut takes a little more time to make it match up perfectly to the first. You can paint, powdercoat or chrome your fender struts, or if you are using a stainless steel DIY Fender Strut Kit you can polish them up and call it a day!
This article was originally written in 2010 as I built my first land speed race bike, a 1955 Triumph named 'Poison Ivy'. These same struts were chromed and are still in use, having set two world land speed records at Bonneville Speed Week in 2011, and still going strong! Like this! Check out our another project how we install a rear fender on a Triumph with easy step by step.