Brake Changes
 

Is there any problem with switching the brake fluid holder on the handle bars from a stock rectangle to the cylinder that comes on the newer F4i? I have a 2003 and I want to change it to the cylinder that comes on the newer models. I thought that as long as it is the same capacity it will provide the same psi in the brake lines.

Yes. I asked the dealer about this. it's designed to enable some kind of 'piston', basically when you pull your brake lever, how the fluid is forced into the line, engaging your brakes. With the circular one, it engages differently, thus, some rectangular, some cylindrical. I wish I knew what the part was.

All f4i's have the rectangles FYI.

So to answer your question, no, not without money that isn't worth spending to a cylindrical container. Also it will interfere with the windscreen, since it sits up higher.

NO

You can install a cylinder setup from a different bike. I've seen people swap them from Yamahas and Suzukis. I don't know much more about the swap though.

F4i never had a cylinder. You must be thinking of the RR or a different bike.

And to elaborate on others, no you can't change just the brake fluid reservoir. You'll need to change to a different master cylinder as well. Which is certainly doable, just takes a little effort.