Michael Moore
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While I have the 2014 CTX forks apart I thought I'd determine just how much the stanchion tubes can be pulled up through the clamps before things begin to touch.
With the top of the stanchion (not the cap, the actual tube) at 8 mm (5/16") above the upper fork clamp the fender just kisses the mounting bracket at the middle/bottom of the radiator. This is with clean/dry parts; with oil in the tubes the hydraulic lock of the bottoming cone on the damper rod might keep the sliders from coming up the last 1-2 mm.
The stanchions should be reasonably stiff but you should presume that a worst-case "braking while hitting a bump hard enough to bottom the forks" will cause them to bend back a little. The 35 mm Ceriani RR forks on my 500 Yamaha road racer would deflect 6-8 mm under heavy braking (on a smooth race track) and leave a bit of rubber on the front of the fairing. The CTX forks should be almost 2X as stiff as the Cerianis but there is an additional two hundred pounds of extra weight on the bike (and 50 pounds on the rider, sad to say) encouraging the forks to deflect.
There is room between the fender and tire (Michelin PR4) to accommodate a bit of deflection, but I'd stick with a maximum of 8 mm, why risk scratching the fender?
Of course, you should always confirm clearances when modifying your own bike and not go with what some guy on the Internet said.
With the top of the stanchion (not the cap, the actual tube) at 8 mm (5/16") above the upper fork clamp the fender just kisses the mounting bracket at the middle/bottom of the radiator. This is with clean/dry parts; with oil in the tubes the hydraulic lock of the bottoming cone on the damper rod might keep the sliders from coming up the last 1-2 mm.
The stanchions should be reasonably stiff but you should presume that a worst-case "braking while hitting a bump hard enough to bottom the forks" will cause them to bend back a little. The 35 mm Ceriani RR forks on my 500 Yamaha road racer would deflect 6-8 mm under heavy braking (on a smooth race track) and leave a bit of rubber on the front of the fairing. The CTX forks should be almost 2X as stiff as the Cerianis but there is an additional two hundred pounds of extra weight on the bike (and 50 pounds on the rider, sad to say) encouraging the forks to deflect.
There is room between the fender and tire (Michelin PR4) to accommodate a bit of deflection, but I'd stick with a maximum of 8 mm, why risk scratching the fender?
Of course, you should always confirm clearances when modifying your own bike and not go with what some guy on the Internet said.
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