A fork brace was one of the first things I added to my Concours. To me the handlebars felt disconnected from the front tire. There was a delay from my input to the bike's reaction. When going through turns I had to make tiny corrections to keep the bike on track. The only things connecting the fork sliders together, besides the front axle, is a flimsy fender stay. Many consider the fender stay to be a fork brace. The early models' stay rests atop of the fender and the late models' beneath it. Neither one is rigid enough to act as a fork brace.
Without a proper brace, bumps and side forces let the sliders work out of synch with eachother. These forces flex the axle, twist the fork tubes, and allow the front wheel to wobble. Not very much but just enough. It's just a matter of degrees. The Concours' fork tubes, at 41 mm diameter, are relatively small for such a heavy bike. Anything that reinforces the front suspension helps prevent the tubes from twisting or flexing. The fork brace grips the tops of the sliders and shares these forces with the axle. Along with the axle, the brace creates a rectangular frame with it at the top, axle at the bottom, and the sliders as the sides. It forces them all to act as a single rigid unit.
This means that the front wheel will track better through turns. It helps reduce wobbles, quickens turn in, and reduces wandering over racked and rain grooved surfaces (tram-lining). It may even cure male pattern baldness. The improvements are immediate. Add firmer straight wound springs, Race Techs's cartridge emulators, and 15 weight fork oil and you've got as modern a front suspension as the Concours will ever have short of a sport bike fork transplant. Top it off with a ZZR1200, ZG1400, or aftermarket rear shock absorber, or at least fresh 15 weight shock oil in the original, to balance everything. There are COG Industry Members that make Concours accessories, among them fork braces. They are all beautifully made, structurally strong, easily installed, and reasonably priced.
NOTE: Braces for '86 thru '98 Concours will not fit the '99 thru '06 Connies. Their sliders were machined to accept small fork shields. These must be sacrificed when installing a fork brace. Braces for those model years are available with brace mounted fork shields. Some braces utilize shims to make up for the machining. Check with the vendor for the correct brace for your bike.
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