I have a interest replacing my f3 forks with f4 - has anyone tried it?What is the f4 fork length ?Reason for the conversation1) On my front forks my internal dampers don't adjust.2) Better brakes

 

You probably need the whole front end. F4 forks are bigger diameter, so you need the triple clamps, handlebars, wheel, axle, spacers, brake rotors, calipers, master cylinder, etc, etc, THE WHOLE FRONT END. Have your F3 forks rebuild with fresh seals, bushings, fluid, springs for your weight. As far as brakes go, good quality pads, fresh brake fluid, and braided brake lines. If your brake rotors are straight and still thick enough, have them glass beaded. It will be cheaper than trying to put a front end of a different bike on and heres the best part...........its all bolt on and you already have the front end. If you do rebuild what you have, they/you should be able to get the adjuster working again.

 

I'm pretty sure the F3 brakes are the same as the F4 as far as rotors go, 296mm floating, calipers and master cylinder not sure. As the F series Honda's evolved, they generally lost weight so an upgrade in bigger brakes werent necessary since there was not as much to stop. For example 87-90 Hurricane 600 has the same brakes as 91-94 F2. F2 has more power and less weight. Even though F3 brakes were an upgrade compared to the F2 brakes.